Use of Optiflow THRIVE High-Flow Nasal Oxygen System versus a Non-rebreather Oxygen Delivery Device in Patients with Increased Risks of Airway Obstruction in Interventional Radiology Procedures: A Randomized Pilot Study

Use of Optiflow THRIVE High-Flow Nasal Oxygen System versus a Non-rebreather Oxygen Delivery Device in Patients with Increased Risks of Airway Obstruction in Interventional Radiology Procedures: A Randomized Pilot Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Use of Optiflow THRIVE High-Flow Nasal Oxygen System versus a Non-rebreather Oxygen Delivery Device in Patients with Increased Risks of Airway Obstruction in Interventional Radiology Procedures: A Randomized Pilot Study Gang Zheng, Mike Hernandez, Carin Hagberg This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8165967/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 12 You are reading this latest preprint version Abstract Background The room configuration in interventional radiology procedures hinders simultaneous access to the patient’s airway and anesthesia machines, and this issue may lead to suboptimal sedation levels in patients with increased risks of airway obstruction owing to patient safety concern. We conducted a randomized trial to evaluate the effectiveness of using a high-flow nasal oxygen (HFNO) device (F&P Optiflow™) versus a standard non-rebreather oxygen delivery device to reduce airway obstruction and improve patient outcomes during anesthesia among patients with increased risks of airway obstruction. Methods Patients at increased risks of airway obstruction were randomized to receive 100% oxygen at a rate of either 70 L/min (HFNO group) or 8 L/min (standard-of-care [SoC] group) along with a continuous intravenous propofol infusion to achieve unconsciousness. We evaluated the total length of desaturation episodes [ToLDE] defined as oxygen saturation [SpO 2 ] ≤92%, the number of desaturation episodes, and the time spent in the postanesthesia care unit (PACU). The level of sedation was assessed using the number of bispectral index (BIS) episodes (defined as episodes of BIS value ≥ 61), and patients’ PACU self-reported symptoms. Results The study included 101 patients, 50 in the HFNO group and 51 in the SoC group. The mean ToLDE time was 0.34 minutes (median, 0; range 0-6.5 minutes) in the HFNO group and 0.97 minutes (median, 0; range 0-19.8 minutes) in the SoC group ( P = 0.158). The proportion of patients experiencing at least one desaturation episode was 14% in the HFNO group and 26% in the SoC group ( P = 0.212). The median total number of BIS episodes was higher in the SoC group (4; range, 0–19) than the HFNO group (2; range, 0–15; P = 0.005). Median PACU stay was 20 minutes (range, 0–60) in the HFNO group and 26 minutes (range, 5–60) in the SOC group ( P = 0.076). Six of 50 patients (12%) in the HFNO group and 8 of 51 (16%) in the SoC group reported PACU complaints and the complaints were less severe in the HFNO group. Conclusions HFNO was not superior to a standard non-rebreather oxygen delivery device in preventing hypoxic events among patients with increased risks of airway obstruction undergoing moderate to deep sedation. However, HFNO may reduce the need for airway interventions and improve the overall patient experience and thus warrants further investigation. Trial registration: ClinicalTrials.gov ID: NCT04171037; Date of original registration: November 19, 2019; This study was retrospectively registered. Study principal investigator: Gang Zheng; This manuscript adheres to the applicable Consolidated Standards of Reporting Trials (CONSORT) guidelines. Figures Figure 1 Figure 2 Figure 3 INTRODUCTION Positioning patients with increased risks of airway obstruction flat during an interventional radiology procedure, particularly when the patient is under moderate or deep sedation, increases the risk of airway obstruction. The typical room setup in these procedures hinders simultaneous access to the patient’s airway and the anesthesia machine, which can lead to suboptimal sedation levels in these people owing to airway safety concerns. These patients often report being awake and experiencing procedural pain. Clinical reports have suggested that high-flow nasal oxygen (HFNO) prolongs safe apneic oxygenation time and reduces hypoxic events. ( 1 , 2 , 3 ) This randomized pilot study evaluated the effectiveness of using a HFNO device (F&P Optiflow™) versus a standard non-rebreather oxygen delivery device to reduce airway obstruction and improve patient experience during anesthesia among patients with increased risks of airway obstruction. We hypothesized that using a HFNO in patients with increased risks of airway obstruction was superior to using a standard non-rebreather to delivery 100% oxygen in reducing airway-related adverse events. METHODS Ethical Approvals This study was approved by the Institutional Review Board at The University of Texas MD Anderson Cancer Center (IRB2019-0348) and was registered in ClinicalTrials.gov (NCT04171037) and in the Clinical Trials Reporting Program database (NCI-2019-07291). All patients provided informed consent. Led by principal investigator Gang Zheng and supported by Fisher & Paykel Healthcare, this study was a prospective randomized controlled pilot study. This manuscript adheres to the applicable Consolidated Standards of Reporting Trials (CONSORT) guidelines. Study Overview Patients were randomized in a 1:1 ratio by the Clinical Oncology Research System (MD Anderson copyright 2000–2007) to receive either HFNO or the standard of care (SoC). Random block sizes were used to ensure numerical balance between study arms. Patients in the HFNO group received 100% oxygen via an Optiflow system (AA030 Optiflow Trace, Fisher & Paykel Healthcare, New Zealand), and patients in the SoC group received 100% oxygen via a non-rebreather face mask (Vyaire Medical, USA). A focused airway history and bedside airway assessment were conducted and informed consent was obtained in the preoperative area. During the procedure, all patients in both groups received a continuous intravenous propofol infusion. For patients in the HFNO group, the oxygen flow rate began at 50 L/min and was increased to 70 L/min after the initiation of a propofol infusion and was maintained at 70 L/min until the end of the procedure. For patients in the SoC group, the oxygen flow rate was maintained at 8 L/min throughout the entire procedure. Patients’ oxygen saturation (SpO 2 ) levels were monitored and manually recorded. The bispectral index (BIS) was used to monitor the level of sedation in both groups. Postoperative assessments with a standard checklist were performed in the postanesthesia care unit (PACU) once patients were fully awake. Patients reported if they experienced any awareness during the procedure, sore jaw or tongue, dysphagia, or dysphonia. Self-reported symptoms in the PACU were recorded for up to 30 minutes after PACU admission, and the length of the PACU stay in minutes was recorded. Study Endpoints The primary endpoint was the total length (in minutes) of all desaturation episodes (ToLDE) that a patient experienced during a 60-minute observation window starting from the initiation of the propofol infusion. A desaturation episode was defined as a drop in SpO 2 to 92% or lower. Secondary endpoints were the number of desaturation episodes, the number of BIS episodes (defined as episodes of BIS value ≥ 61), PACU observation time, and PACU self-reported symptoms. Sample Size Justification With 50 patients per study arm, the precision for the bounds of a 2-sided 95% confidence interval (CI) for the ToLDE time would extend 0.39 minutes on each side of the observed mean, assuming a common standard deviation of 1.0 minute per group. If the ToLDE time showed a highly skewed distribution, the proportion of patients experiencing at least one desaturation episode would be estimated for each study arm. Assuming a 15% desaturation rate and n = 50 patients, the half-width of a 2-sided 95% CI would extend approximately 10 percentage points on each side of the expected proportion (nQuery Advisor, v. 7.0). Patient Enrollment A designated study faculty member reviewed all patients scheduled for total intravenous anesthesia procedures in the daily interventional radiology schedule between November of 2019 and July of 2023 at The University of Texas MD Anderson Cancer Center. Eligible candidates included individuals diagnosed with obstructive sleep apnea (OSA), whether they used a continuous positive airway pressure device at home. Additionally, patients with a body mass index of 32 kg/m 2 or greater and a neck circumference of 40 cm or larger were potentially eligible irrespective of their OSA status. We excluded individuals who were 18 years old or younger or who had severe organ/system decompensation rendering them unable to tolerate moderate sedation; current pulmonary disease requiring supplemental oxygen; significantly compromised airways due to aerodigestive oncology-related mass effects, making minimal sedation or awake airway intubation the preferred anesthetic option; or a baseline SpO 2 reading of 92% or lower. Data Collection We collected data on patient demographics, American Society of Anesthesiologists physical status, Mallampati score, instances and duration of oxygen desaturation, occurrences, and duration of BIS episodes, and PACU self-reported symptoms. Study personnel manually recorded the instances and duration of oxygen desaturation and BIS episodes. PACU self-reported symptoms were gathered for each patient either when they met institutional discharge criteria or within 30 minutes of their PACU admission. Statistical Analyses Descriptive statistics were used to summarize continuous outcomes and patient characteristics, and scatterplots were used to explore distributional characteristics and bivariate relationships, respectively. Interval estimates were computed for continuous variables, such as ToLDE time, for each study arm independently using a 2-sided 95% CI. Exploratory analyses between study arms were conducted using the Wilcoxon rank-sum test for continuous variables and Fisher’s exact test for categorical variables. Logistic regression was used to determine the association between study arm and the experience of at least one episode of desaturation while adjusting for covariates of interest. Analyses were performed using Stata v. 16 (StataCorp), and P values less than 0.05 were considered statistically significant. Table 1. Patient Characteristics by Study Arm Characteristic HFNO (N = 50) SoC (N = 51) Total (N = 101) Age, years Mean (SD) 60.18 (11.96) 60.96 (11.97) 60.57 (11.91) Median (IQR) 62 (50.75–70.00) 64 (54.00–68.00) 63 (51.50–69.00) Range 34.00–83.00 31.00–82.00 31.00–83.00 BMI a , kg/m 2 Mean (SD) 37.02 (5.84) 39.46 (7.96) 38.26 (7.07) Median (IQR) 35.99 (33.60–40.09) 38.08 (34.72–45.51) 37.33 (33.74–43.48) Range 22.35–52.07 24.92–67.05 22.35–67.05 Height a , cm Mean (SD) 170.99 (11.45) 168.96 (9.76) 169.96 (10.62) Median (IQR) 169 (163.00–179.35) 169 (162.00–176.00) 169 (162.70–176.38) Range 147.00–192.00 145.00–188.00 145.00–192.00 Weight b , kg Mean (SD) 107.12 (22.81) 109.36 (21.6) 108.24 (22.12) Median (IQR) 110.6 (95.50–117.20) 108.5 (95.50–120.10) 109.25 (95.50–118.50) Range 36.40–162.00 62.40–159.90 36.40–162.00 Sex, n (%) Female 22 (44) 23 (45) 45 (45) Male 28 (56) 28 (55) 56 (55) ASA status c , n (%) II 1 (2) 2 (4) 3 (3) III 49 (98) 48 (96) 97 (97) Mallampati score c , n (%) I 1 (2) 1 (2) 2 (2) II 14 (28) 17 (34) 31 (31) III 33 (66) 32 (64) 65 (65) IV 2 (4) 0 (0) 2 (2) Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; IQR, interquartile range; HFNO, high-flow nasal oxygen; SD, standard deviation; SoC, standard of care. a Missing data for 1 patient in the HFNO group. b Missing data for 3 patients in the HFNO group and 4 patients in the SoC group. c Missing data for 1 patient in the SoC group. RESULTS Patient Characteristics A total of 114 patients were identified who were eligible, 6 patients declined the study, and 108 patients were randomized to the study arms. Of the patients who were randomized, 6 patients had screening failures prior to the procedure owing to a last-minute change of the procedure plan by the procedure physicians and one patient had no follow-up measurements due to the last-minute change of the anesthesia plan by the patient. Thus, 101 patients were deemed evaluable for the primary endpoint, with 50 patients in the HFNO group and 51 patients in the SoC group (Fig. 1 ). Patient characteristics are listed in Table 1, and airway focused information, etc ., relevant comorbidities and bedside airway measurements, are listed in Table 2 . Table 2 Clinical Measurements and History of Comorbidities by Study Arm HFNO (N = 50) SoC (N = 51) P Total (N = 101) Clinical measurements Neck circumference, cm Mean (SD) 43.46 (5.39) 43.78 (4.5) 43.62 (4.94) Median (IQR) 42 (39.88–46.25) 43.5 (40.00–47.00) 0.514 a 43 (40.00–47.00) Range 35.00–58.00 35.00–56.00 35.00–58.00 Inter-incisor gap distance, cm Mean (SD) 5.62 (1.24) 5.76 (1.32) 5.69 (1.28) Median (IQR) 6 (4.88–6.50) 6 (4.50–7.00) 0.628 a 6 (4.50–6.50) Range 3.20–10.00 3.50–9.00 3.20–10.00 Thyromental distance, cm Mean (SD) 8.16 (1.88) 8.03 (1.9) 8.1 (1.88) Median (IQR) 8 (7.00–9.62) 8 (6.50–9.00) 0.669 a 8 (7.00–9.00) Range 4.00–12.00 5.00–14.00 4.00–14.00 Sternomental distance, cm Mean (SD) 13.01 (2.32) 12.6 (1.91) 12.8 (2.12) Median (IQR) 13 (11.38–14.50) 12 (11.00–14.00) 0.303 a 13 (11.00–14.00) Range 7.00–18.00 9.00–18.00 7.00–18.00 Comorbidities History of snoring, n (%) No 21 (42) 16 (31) 0.306 b 37 (37) Yes 29 (58) 35 (69) 64 (63) History of DMV, n (%) No 50 (100) 51 (100) ---- c 101 (100) OSA, n (%) No 22 (44) 18 (35) 0.419 b 40 (40) Yes 28 (56) 33 (65) 61 (60) BMI > 35 kg/m 2 , n (%) No 25 (50) 18 (35) 0.161 b 43 (43) Yes 25 (50) 33 (65) 58 (57) Anterior DMV, n (%) No 50 (100) 51 (100) ---- c 101 (100) Age > 55 years, n (%) No 22 (44) 18 (35) 0.419 b 40 (40) Yes 28 (56) 33 (64) 61 (60) Edentulousness, n (%) No 35 (70) 39 (76) 0.506 b 74 (73) Yes 15 (30) 12 (24) 27 (27) Abbreviations: BMI, body mass index; DMV, difficult mask ventilation; IQR, interquartile range; HFNO, high-flow nasal oxygen; OSA, obstructive sleep apnea; SD, standard deviation; SoC, standard of care. a Wilcoxon rank-sum test P value. b Fisher’s exact test P value. C No statistical comparison. TOLDE and Number of Desaturation Episodes The mean ToLDE time in the HFNO group was 0.34 minutes (median, 0 minutes; range, 0–6.5 minutes), and the mean ToLDE in the SoC group was 0.97 minutes (median, 0 minutes; range: 0–19.8 minutes; P = 0.158; Table 3 ). The distribution of ToLDE time was highly skewed because most patients (80%) failed to experience desaturation episodes. Table 3 ToLDE time, Length of PACU Observation, and BIS Episodes by Study Arm HFNO (N = 50) SoC (N = 51) P Total (N = 101) ToLDE time, min Mean (SD) 0.34 (1.16_ 0.97 (3.25) 0.66 (2.46) Median (IQR) 0 (0.00–0.00) 0 (0.00–0.02) 0.158 a 0 (0.00–0.00) Range 0.00–6.50 0.00–19.78 0.00–19.78 Total SpO 2 ≤ 92% episodes 0 43 (86) 38 (75) 0.514 b 81 (80) 1 3 (6) 4 (8) 7 (7) 2 2 (4) 4 (8) 6 (6) 3 or more 2 (4) 5 (10) 7 (7) Experienced at least 1 SpO 2 ≤92% episode, n (%) No 43 (86) 38 (74) 0.212 b 81 (80) Yes 7 (14) 13 (26) 20 (20) Min SpO 2 c , % n = 7 n = 13 N = 20 Mean (SD) 90 (2.83) 88.62 (3.91) 89.1 (3.55) Median (IQR) 91 (87.00–92.00) 90 (84.00–92.00) 0.349 a 91 (85.50–92.00) Range 85.00–92.00 81.00–92.00 81.00–92.00 Max SpO 2 c , % n = 7 n = 13 N = 20 Mean (SD) 91.86 (0.38) 90.38 (2.93) 90.9 (2.45) Median (IQR) 92 (92.00–92.00) 92 (90.00–92.00) 0.203 a 92 (91.00–92.00) Range 91.00–92.00 84.00–92.00 84.00–92.00 Length of PACU observation d , min Mean (SD) 24.62 (17.87) 30.39 (16.25) 27.53 (17.23) Median (IQR) 20 (12.25–39.00) 26 (18.00–44.00) 0.076 a 23 (14.00–41.00) Range 0.00–60.00 5.00–60.00 0.00–60.00 Total BIS value ≥61 episodes Mean (SD) 3 (3.1) 4.69 (3.75) 3.85 (3.53) Median (IQR) 2 (1.00–4.25) 4 (2.00–6.00) 0.005 a 3 (1.00–5.00) Range 0.00–15.00 0.00–19.00 0.00–19.00 Experienced at least one BIS≥61 episode, n (%) No 10 (20) 5 (10) 0.172 b 15 (15) Yes 40 (80) 46 (90) 86 (85) Abbreviations: BIS, bispectral index; HFNO, high-flow nasal oxygen; IQR, interquartile range; Max, maximum; Min, minimum; PACU, post-anesthesia care unit; SD, standard deviation; SoC, standard of care; SpO 2 , oxygen saturation; ToLDE, total length of desaturation episode. a Wilcoxon rank-sum test P value. b Fisher’s exact test P value. c Of patients who experienced a desaturation episode. d Missing data for 1 patient in the SoC group. Of all 101 patients, 20 (20%) experienced at least one desaturation episode. In the HFNO group, 7 patients (14%; 95% CI, 6%–27%) experienced at least one desaturation episode, and in the SoC group, 13 patients (26%; 95% CI, 14%–40%) experienced at least one desaturation episode ( P = 0.212). Among the 20 patients experiencing desaturation episodes, ToLDE time ranged from approximately 1 second to 19.8 minutes (Table 3 ). Among the patients who experienced desaturation episodes, the mean ToLDE time was similar in the HFNO group (2.44 minutes; 95% CI, 0.36–4.52 minutes) and in the SoC group (3.79 minutes; 95% CI, 0.35–7.23 minutes). BIS Episodes and PACU Observation Time The median total number of BIS episodes that a patient experienced was significantly higher for patients in the SoC group (4; range, 0–19) than for patients in the HFNO group (2; range, 0–15; P = 0.005; Table 3 and Fig. 2 ). The median length of PACU observation time was longer for patients in the SoC group (26 minutes; range, 5–60 minutes) than patients in the HFNO group (20 minutes; range, 0–60 minutes; P = 0.076; Fig. 3 ). PACU Self-Reported Symptoms Patients reported experiencing jaw pain, sore tongue, and dysphagia. In the SoC group, 8 complaints (16%) were reported: jaw pain (n = 2; severe), sore tongue (n = 2; moderate), and difficulty swallowing (n = 4; mild). In the HFNO group, 6 complaints (12%) were reported: sore tongue (n = 4; mild) and dysphagia (n = 2; mild); no jaw pain was reported in this group. The proportion of patients reporting complaints was not significantly different between study arms (HFNO, 12%, vs. SoC, 16%; P = 0.592). None of the patients in the study experienced dysphonia. Association between Patient Comorbidities and Desaturation Episodes Although the study arms were not significantly different with respect to OSA (HFNO, 56%, vs. SoC, 65%; P = 0.419) or obesity (HFNO 50% vs. SoC 65%; P = 0.161), both comorbidities were more prevalent in the SoC group. OSA, obesity, and other comorbidities and clinical characteristics are summarized in Table 2 . Findings from univariable logistic regression to assess the independent associations between each comorbidity and desaturation episodes indicated that patients with obesity were 14% more likely to experience a desaturation episode (odds ratio [OR] = 1.14; 95% CI, 0.42–3.09; P = 0.795) but patients with OSA were 24% less likely to experience a desaturation episode (OR = 0.76; 95% CI, 0.28–2.04; P = 0.582). The multivariable model showed that using HFNO relative to SoC reduced the odds of desaturation by 54% (OR = 0.46; 95% CI, 0.16–1.30; P = 0.143) after adjusting for obesity (OR = 1.02; 95% CI, 0.37–2.84; P = 0.963) and OSA (OR = 0.70; 95% CI, 0.26–1.92; P = 0.490). DISCUSSION Although previous studies and meta-analyses indicated that HFNO significantly reduces the incidence and duration of hypoxic events in patients at risk of hypoxemia under deep sedation, ( 6 , 7 ) our study found that using a HFNO at the rate of 70 L/min of 100% oxygen in patients who were obese or had obstructive sleep apnea (OSA) was not superior to using a standard non-rebreather to deliver 100% oxygen at a rate of 8 L/min in reducing airway-related adverse events. Specifically, there were no significant differences in the ToLDE ( P = 0.158) and the proportion of patients experiencing desaturation episodes ( P = 0.212) between the HFNO and SoC groups during interventional radiology procedures. These findings do not support our study hypothesis. A previous multicenter study of 379 participants found that HFNO significantly reduced the incidence of desaturation episodes (SpO 2 ≤ 92%) by 23.4% ( P < 0.001) in patients undergoing deep sedation for gastrointestinal endoscopies. ( 7 ) However, our study did not observe similar outcomes, which may be attributed to differences in patient populations. Our study focused on patients with increased risks of airway obstruction, whereas the previous study included patients with various systemic comorbidities related to respiration and circulation. In our study, the median body mass index was 37.33 kg/m 2 (IQR, 33.74–43.48 kg/m 2 ), compared with 27 kg/m 2 (IQR, 23.9–30.5 kg/m 2 ) in the previous study. Additionally, our patients underwent interventional radiology procedures in a flat position, in contrast to the 15- to 30-degree upper body elevation used during the gastrointestinal endoscopies in the previous study; the flat position likely exacerbated the risk of airway obstruction and respiratory complications. The combination of a flat position and sedation in obese patients not only increases the risk of upper airway obstruction and overall respiratory workload but also exacerbates the respiratory mechanism by reducing the functional residual capacity and increasing the closing capacity of the lungs. When the mouth is closed, HFNO provides approximately 1 cm H 2 O positive airway pressure per 10 L/min oxygen flow, reaching a maximum of 7 to 8 cm H 2 O at 70 L/min, (8,9) and is described as “dynamic, not set and not constant ”( 10 ) . However, maintaining a patent airway requires constant positive airway pressure above a critical level that varies between individuals. ( 11 ) In our study, 14% of patients in the HFNO group experienced desaturation episodes. This finding aligns with others from meta-analyses focused on obese patients, ( 12 , 13 , 14 ) which suggests that although HFNO prolongs safe apnea, it does not significantly reduce hypoxic events. Another meta-analysis of 10 randomized controlled studies published between 2014 and 2021 (n = 564; body mass index, 33–52 kg/m 2 ) demonstrated that use of HFNO prolonged safe apnea time but did not reduce hypoxic events. ( 13 ) Further, Bright et al. conducted a meta-analysis and reported that use of a high-flow nasal cannula was not superior to use of a regular face mask in reducing hypoxic events (OR = 0.49; 95% CI, 0.15–1.63; P = 0.24). (14) Although our findings did not support our hypothesis, we identified some benefits of using HFNO in interventional radiology procedures, suggesting that further investigation of HFNO is warranted. These benefits included fewer episodes of a BIS value of 61 or above ( P = 0.005), shorter PACU stays ( P = 0.07), and fewer and less severe PACU self-reported symptoms in the HFNO group compared with the SoC group. Frequent episodes of BIS value 61 or above during total intravenous anesthesia typically indicate inadequate sedation levels. Study Limitations This study has a few limitations. First, the electronic anesthesia record was incapable of capturing all the adverse events, the manual data collection in this study may have affected the preciseness of the data. Second, the study included both patients with obesities and patients with OSA. The underlying pathophysiologic and respiratory mechanisms of OSA and obesity are not the same, although airway obstruction is a primary feature in both conditions. For instance, the closing capacity and functional residual capacity are less affected in non-obese patients than in obese patients. CONCLUSIONS In this pilot study, HFNO did not demonstrate superior improvement to the use of a standard non-rebreather oxygen delivery device in preventing hypoxic events among patients with increased risks of airway obstruction during interventional radiology procedures. However, HFNO may reduce the need for airway intervention and shorten postoperative recovery time, enhancing the overall patient experience. The observed effects were nonsignificant and inconclusive; further investigation is needed to determine their clinical significance. Abbreviations HFNO high-flow nasal oxygen PACU postanesthesia care unit OSA obstructive sleep apnea SoC standard-of-care ToLDE total length of desaturation episodes BIS bispectral index CONSORT Consolidated Standards of Reporting Trials OR odds ratio CI confidence interval SpO 2 peripheral oxygen saturation. Declarations Ethics approval and consent to participate:This study was approved by the Institutional Review Board at The University of Texas MD Anderson Cancer Center (IRB2019-0348) and was registered in ClinicalTrials.gov (NCT04171037) and in the Clinical Trials Reporting Program database (NCI-2019-07291). All patients provided a signed informed consent. Data Availability: Availability of data and materials are limited in the report and analysis. Funding Statement: The University of Texas MD Anderson Cancer Center and the National Cancer Institute provided the primary sponsorship for this study. Fisher & Paykel Healthcare (New Zealand) provided funding support. Conflicts of Interest: This study received funding support from Fisher & Paykel Healthcare (New Zealand). Authors' contributions: 1. Gang Zheng, this author helped with the development of the study protocol, data verification, and writing manuscript. 2. Mike Hernandez, this author helped with the development of the study protocol, data analysis and writing manuscript. 3. Carin Hagberg, this author helped with the development of the study protocol, manuscript editing and finalization of the article. Acknowledgements: The authors of this article would like to acknowledge the contributions of Ms. Raven Bailey, BS, Mr. Tyrone Burnett Jr., BS, and Mr. Tariq A. Syed, MS, who were the Senior Clinical Study Coordinators in the Division of Anesthesiology, Pain Management and Critical Care at The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. Both Mr. Burnett and Mr. Syed helped with the protocol development and documentation, and Ms. Bailey helped with data collection and data organization. We thank Madison Semro, Associate Scientific Editor, and Stephanie Deming, Senior Scientific Editor, in the Research Medical Library at The University of Texas MD Anderson Cancer Center for editing this article. 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Anaesth Intensive Care. 2011;39(6):1103–10. Groves N, Tobin A. High flow nasal oxygen generates positive airway pressure in adult volunteers. Aust Crit Care. 2007;20(4):126–31. Thiruvenkatarajan V, Sekhar V, Wong DT, Currie J, Wijk RV, Ludbrook GL. Effect of high-flow nasal oxygen on hypoxaemia during procedural sedation: a systematic review and meta-analysis. Anaesthesia. 2023;78(1):81–92. Nay MA, Fromont L, Eugene A, et al. High flow nasal oxygenation or standard oxygenation for gastrointestinal endoscopy with sedation in patients at risk of hypoxaemia: a multicentre randomized controlled trial (ODEPHI trial). Br J Anaesth. 2021;127(1):133–42. Parke RL, Bloch A, McGuinness SP. Effect of very high flow nasal therapy on airway pressure and end expiratory lung impedance in healthy volunteers. Respir Care. 2015;60(10):1397–430. Vieira F, Bezerra FS, Coudroy R, et al. High-flow nasal cannula compared with continuous positive airway pressure: a bench and physiological study. J Appl Phys. 2022;132:1580–90. Fisher & Paykel Healthcare. Accessed Nov 6, 2023. https://www.fphcare.com Sullivan CE, Berthon-Jones M, Issa FG. Nocturnal nasal-airway pressure for sleep apnea. N Engl J Med. 1983;309(2):112. Guy L, Christensen R, Dodd B, et al. The effect of transnasal humidified rapid-insufflation ventilator exchange (THRIVE) versus nasal prongs on safe apnoea time in paralysed obese patients: a randomized controlled trial. Br J Anaesth. 2022;128(2):375–81. Hung KC, Ko CC, Chang PC, et al. Efficacy of high-flow nasal oxygenation against peri-and post-procedural hypoxemia in patients with obesity: a meta-analysis of randomized controlled trials. Sci Rep. 2022;12(1):6448. Bright MR, Harley WA, Velli G, Zahir SF, Eley V. High-flow nasal cannula for apneic oxygenation in obese patients for elective surgery: a systematic review and meta-analysis. Anesth Analg. 2023;136(3):483–93. Additional Declarations Competing interest reported. The study received funding support from Fisher & Paykel Healthcare (New Zealand) Supplementary Files CONSORT2010Checklist.pdf Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 02 Mar, 2026 Reviews received at journal 22 Feb, 2026 Reviewers agreed at journal 19 Feb, 2026 Reviews received at journal 17 Feb, 2026 Reviewers agreed at journal 06 Feb, 2026 Reviewers agreed at journal 05 Feb, 2026 Reviewers agreed at journal 19 Dec, 2025 Reviewers invited by journal 16 Dec, 2025 Editor assigned by journal 08 Dec, 2025 Editor invited by journal 05 Dec, 2025 Submission checks completed at journal 04 Dec, 2025 First submitted to journal 04 Dec, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8165967","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":561026677,"identity":"6b4b5395-e0a8-4a63-8e2b-5a8118733620","order_by":0,"name":"Gang 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1","display":"","copyAsset":false,"role":"figure","size":45068,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCONSORT Diagram. HFNO, high-flow nasal oxygen.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8165967/v1/7a9e4ef48e287cb7e001787e.jpg"},{"id":98757435,"identity":"03dbeeb7-1b93-4c60-8ccf-f790cda418a0","added_by":"auto","created_at":"2025-12-22 09:38:14","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":89675,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTotal Number of Episodes (Bispectral Index [BIS] Value ≥61) by Study Arm. HFNO, high-flow nasal oxygen.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8165967/v1/bf9849085a3aa1aa2ea50d91.png"},{"id":98757425,"identity":"244b7e96-d1b3-40b9-bbb8-7d1c9b6c1fa3","added_by":"auto","created_at":"2025-12-22 09:38:13","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":185614,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePost-Anesthesia Care Unit Observation Time by Study Arm. HFNO, high-flow nasal oxygen.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-8165967/v1/62d79c7f58be6bd265b65561.png"},{"id":98783246,"identity":"242968ce-de8c-4dd6-ad5a-68de7b99482b","added_by":"auto","created_at":"2025-12-22 12:41:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1410414,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8165967/v1/772277dd-2dea-4253-9df7-350713329883.pdf"},{"id":98757444,"identity":"29794975-84c7-4468-9fdf-a14397ca1464","added_by":"auto","created_at":"2025-12-22 09:38:15","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":1533493,"visible":true,"origin":"","legend":"","description":"","filename":"CONSORT2010Checklist.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8165967/v1/e0c0d42d436f8e5f483cdf60.pdf"}],"financialInterests":"Competing interest reported. The study received funding support from Fisher \u0026 Paykel Healthcare (New Zealand)","formattedTitle":"\u003cp\u003eUse of Optiflow THRIVE High-Flow Nasal Oxygen System versus a Non-rebreather Oxygen Delivery Device in Patients with Increased Risks of Airway Obstruction in Interventional Radiology Procedures: A Randomized Pilot Study\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003ePositioning patients with increased risks of airway obstruction flat during an interventional radiology procedure, particularly when the patient is under moderate or deep sedation, increases the risk of airway obstruction. The typical room setup in these procedures hinders simultaneous access to the patient\u0026rsquo;s airway and the anesthesia machine, which can lead to suboptimal sedation levels in these people owing to airway safety concerns. These patients often report being awake and experiencing procedural pain.\u003c/p\u003e \u003cp\u003eClinical reports have suggested that high-flow nasal oxygen (HFNO) prolongs safe apneic oxygenation time and reduces hypoxic events.\u003csup\u003e(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e This randomized pilot study evaluated the effectiveness of using a HFNO device (F\u0026amp;P Optiflow\u0026trade;) versus a standard non-rebreather oxygen delivery device to reduce airway obstruction and improve patient experience during anesthesia among patients with increased risks of airway obstruction. We hypothesized that using a HFNO in patients with increased risks of airway obstruction was superior to using a standard non-rebreather to delivery 100% oxygen in reducing airway-related adverse events.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eEthical Approvals\u003c/h2\u003e \u003cp\u003eThis study was approved by the Institutional Review Board at The University of Texas MD Anderson Cancer Center (IRB2019-0348) and was registered in ClinicalTrials.gov (NCT04171037) and in the Clinical Trials Reporting Program database (NCI-2019-07291). All patients provided informed consent. Led by principal investigator Gang Zheng and supported by Fisher \u0026amp; Paykel Healthcare, this study was a prospective randomized controlled pilot study. This manuscript adheres to the applicable Consolidated Standards of Reporting Trials (CONSORT) guidelines.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStudy Overview\u003c/h3\u003e\n\u003cp\u003ePatients were randomized in a 1:1 ratio by the Clinical Oncology Research System (MD Anderson copyright 2000\u0026ndash;2007) to receive either HFNO or the standard of care (SoC). Random block sizes were used to ensure numerical balance between study arms. Patients in the HFNO group received 100% oxygen via an Optiflow system (AA030 Optiflow Trace, Fisher \u0026amp; Paykel Healthcare, New Zealand), and patients in the SoC group received 100% oxygen via a non-rebreather face mask (Vyaire Medical, USA). A focused airway history and bedside airway assessment were conducted and informed consent was obtained in the preoperative area.\u003c/p\u003e \u003cp\u003eDuring the procedure, all patients in both groups received a continuous intravenous propofol infusion. For patients in the HFNO group, the oxygen flow rate began at 50 L/min and was increased to 70 L/min after the initiation of a propofol infusion and was maintained at 70 L/min until the end of the procedure. For patients in the SoC group, the oxygen flow rate was maintained at 8 L/min throughout the entire procedure. Patients\u0026rsquo; oxygen saturation (SpO\u003csub\u003e2\u003c/sub\u003e) levels were monitored and manually recorded. The bispectral index (BIS) was used to monitor the level of sedation in both groups.\u003c/p\u003e \u003cp\u003ePostoperative assessments with a standard checklist were performed in the postanesthesia care unit (PACU) once patients were fully awake. Patients reported if they experienced any awareness during the procedure, sore jaw or tongue, dysphagia, or dysphonia. Self-reported symptoms in the PACU were recorded for up to 30 minutes after PACU admission, and the length of the PACU stay in minutes was recorded.\u003c/p\u003e\n\u003ch3\u003eStudy Endpoints\u003c/h3\u003e\n\u003cp\u003eThe primary endpoint was the total length (in minutes) of all desaturation episodes (ToLDE) that a patient experienced during a 60-minute observation window starting from the initiation of the propofol infusion. A desaturation episode was defined as a drop in SpO\u003csub\u003e2\u003c/sub\u003e to 92% or lower. Secondary endpoints were the number of desaturation episodes, the number of BIS episodes (defined as episodes of BIS value\u0026thinsp;\u0026ge;\u0026thinsp;61), PACU observation time, and PACU self-reported symptoms.\u003c/p\u003e\n\u003ch3\u003eSample Size Justification\u003c/h3\u003e\n\u003cp\u003eWith 50 patients per study arm, the precision for the bounds of a 2-sided 95% confidence interval (CI) for the ToLDE time would extend 0.39 minutes on each side of the observed mean, assuming a common standard deviation of 1.0 minute per group. If the ToLDE time showed a highly skewed distribution, the proportion of patients experiencing at least one desaturation episode would be estimated for each study arm. Assuming a 15% desaturation rate and n\u0026thinsp;=\u0026thinsp;50 patients, the half-width of a 2-sided 95% CI would extend approximately 10 percentage points on each side of the expected proportion (nQuery Advisor, v. 7.0).\u003c/p\u003e\n\u003ch3\u003ePatient Enrollment\u003c/h3\u003e\n\u003cp\u003eA designated study faculty member reviewed all patients scheduled for total intravenous anesthesia procedures in the daily interventional radiology schedule between November of 2019 and July of 2023 at The University of Texas MD Anderson Cancer Center. Eligible candidates included individuals diagnosed with obstructive sleep apnea (OSA), whether they used a continuous positive airway pressure device at home. Additionally, patients with a body mass index of 32 kg/m\u003csup\u003e2\u003c/sup\u003e or greater and a neck circumference of 40 cm or larger were potentially eligible irrespective of their OSA status. We excluded individuals who were 18 years old or younger or who had severe organ/system decompensation rendering them unable to tolerate moderate sedation; current pulmonary disease requiring supplemental oxygen; significantly compromised airways due to aerodigestive oncology-related mass effects, making minimal sedation or awake airway intubation the preferred anesthetic option; or a baseline SpO\u003csub\u003e2\u003c/sub\u003e reading of 92% or lower.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eData Collection\u003c/h2\u003e \u003cp\u003eWe collected data on patient demographics, American Society of Anesthesiologists physical status, Mallampati score, instances and duration of oxygen desaturation, occurrences, and duration of BIS episodes, and PACU self-reported symptoms. Study personnel manually recorded the instances and duration of oxygen desaturation and BIS episodes. PACU self-reported symptoms were gathered for each patient either when they met institutional discharge criteria or within 30 minutes of their PACU admission.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStatistical Analyses\u003c/h3\u003e\n\u003cp\u003eDescriptive statistics were used to summarize continuous outcomes and patient characteristics, and scatterplots were used to explore distributional characteristics and bivariate relationships, respectively. Interval estimates were computed for continuous variables, such as ToLDE time, for each study arm independently using a 2-sided 95% CI. Exploratory analyses between study arms were conducted using the Wilcoxon rank-sum test for continuous variables and Fisher\u0026rsquo;s exact test for categorical variables. Logistic regression was used to determine the association between study arm and the experience of at least one episode of desaturation while adjusting for covariates of interest. Analyses were performed using Stata v. 16 (StataCorp), and \u003cem\u003eP\u003c/em\u003e values less than 0.05 were considered statistically significant.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eTable 1. Patient Characteristics by Study Arm\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"683\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristic\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHFNO (N = 50)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSoC (N = 51)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal (N = 101)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eAge, years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e60.18 (11.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e60.96 (11.97)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e60.57 (11.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e62 (50.75\u0026ndash;70.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e64 (54.00\u0026ndash;68.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e63 (51.50\u0026ndash;69.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eRange\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e34.00\u0026ndash;83.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e31.00\u0026ndash;82.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e31.00\u0026ndash;83.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eBMI\u003csup\u003ea\u003c/sup\u003e, kg/m\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e37.02 (5.84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e39.46 (7.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e38.26 (7.07)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e35.99 (33.60\u0026ndash;40.09)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e38.08 (34.72\u0026ndash;45.51)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e37.33 (33.74\u0026ndash;43.48)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eRange\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e22.35\u0026ndash;52.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e24.92\u0026ndash;67.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e22.35\u0026ndash;67.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eHeight\u003csup\u003ea\u003c/sup\u003e, cm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e170.99 (11.45)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e168.96 (9.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e169.96 (10.62)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e169 (163.00\u0026ndash;179.35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e169 (162.00\u0026ndash;176.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e169 (162.70\u0026ndash;176.38)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eRange\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e147.00\u0026ndash;192.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e145.00\u0026ndash;188.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e145.00\u0026ndash;192.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eWeight\u003csup\u003eb\u003c/sup\u003e, kg\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMean (SD)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e107.12 (22.81)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e109.36 (21.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e108.24 (22.12)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMedian (IQR)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e110.6 (95.50\u0026ndash;117.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e108.5 (95.50\u0026ndash;120.10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e109.25 (95.50\u0026ndash;118.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eRange\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e36.40\u0026ndash;162.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e62.40\u0026ndash;159.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e36.40\u0026ndash;162.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eSex, n (%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e22 (44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e23 (45)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e45 (45)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e28 (56)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e28 (55)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e56 (55)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eASA\u0026nbsp;status\u003csup\u003ec\u003c/sup\u003e,\u0026nbsp;n (%)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e1 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e2 (4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e3 (3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eIII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e49 (98)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e48 (96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e97 (97)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eMallampati score\u003csup\u003ec\u003c/sup\u003e, n (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e1 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e1 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e2 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e14 (28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e17 (34)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e31 (31)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eIII\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e33 (66)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e32 (64)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e65 (65)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eIV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 119px;\"\u003e\n \u003cp\u003e2 (4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 117px;\"\u003e\n \u003cp\u003e0 (0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 173px;\"\u003e\n \u003cp\u003e2 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAbbreviations: ASA,\u0026nbsp;American Society of Anesthesiologists; BMI, body mass index; IQR, interquartile range; HFNO, high-flow nasal oxygen; SD, standard deviation; SoC, standard of care.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ea\u003c/sup\u003e Missing data for 1 patient in the HFNO group.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003eb\u003c/sup\u003e Missing data for 3 patients in the HFNO group and 4 patients in the SoC group.\u003c/p\u003e\n\u003cp\u003e\u003csup\u003ec\u003c/sup\u003e Missing data for 1 patient in the SoC group.\u003c/p\u003e\n"},{"header":"RESULTS","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003ePatient Characteristics\u003c/h2\u003e \u003cp\u003eA total of 114 patients were identified who were eligible, 6 patients declined the study, and 108 patients were randomized to the study arms. Of the patients who were randomized, 6 patients had screening failures prior to the procedure owing to a last-minute change of the procedure plan by the procedure physicians and one patient had no follow-up measurements due to the last-minute change of the anesthesia plan by the patient. Thus, 101 patients were deemed evaluable for the primary endpoint, with 50 patients in the HFNO group and 51 patients in the SoC group (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Patient characteristics are listed in Table\u0026nbsp;1, and airway focused information, \u003cem\u003eetc\u003c/em\u003e., relevant comorbidities and bedside airway measurements, are listed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eClinical Measurements and History of Comorbidities by Study Arm\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHFNO (N\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSoC (N\u0026thinsp;=\u0026thinsp;51)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTotal (N\u0026thinsp;=\u0026thinsp;101)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eClinical measurements\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNeck circumference, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43.46 (5.39)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43.78 (4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e43.62 (4.94)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42 (39.88\u0026ndash;46.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43.5 (40.00\u0026ndash;47.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.514\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e43 (40.00\u0026ndash;47.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35.00\u0026ndash;58.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35.00\u0026ndash;56.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e35.00\u0026ndash;58.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInter-incisor gap distance, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.62 (1.24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.76 (1.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.69 (1.28)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (4.88\u0026ndash;6.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6 (4.50\u0026ndash;7.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.628\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6 (4.50\u0026ndash;6.50)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.20\u0026ndash;10.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.50\u0026ndash;9.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.20\u0026ndash;10.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThyromental distance, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.16 (1.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.03 (1.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.1 (1.88)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8 (7.00\u0026ndash;9.62)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8 (6.50\u0026ndash;9.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.669\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8 (7.00\u0026ndash;9.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.00\u0026ndash;12.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.00\u0026ndash;14.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.00\u0026ndash;14.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSternomental distance, cm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13.01 (2.32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.6 (1.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e12.8 (2.12)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13 (11.38\u0026ndash;14.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12 (11.00\u0026ndash;14.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.303\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13 (11.00\u0026ndash;14.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.00\u0026ndash;18.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.00\u0026ndash;18.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.00\u0026ndash;18.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComorbidities\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of snoring, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21 (42)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16 (31)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.306\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e37 (37)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29 (58)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35 (69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e64 (63)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of DMV, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e----\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e101 (100)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOSA, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22 (44)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18 (35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.419\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e40 (40)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28 (56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33 (65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e61 (60)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI\u0026thinsp;\u0026gt;\u0026thinsp;35 kg/m\u003csup\u003e2\u003c/sup\u003e, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25 (50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18 (35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.161\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e43 (43)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25 (50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33 (65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e58 (57)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnterior DMV, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51 (100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e----\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e101 (100)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u0026thinsp;\u0026gt;\u0026thinsp;55 years, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22 (44)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18 (35)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.419\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e40 (40)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28 (56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33 (64)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e61 (60)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEdentulousness, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e35 (70)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39 (76)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.506\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e74 (73)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 (30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12 (24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e27 (27)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eAbbreviations: BMI, body mass index; DMV, difficult mask ventilation; IQR, interquartile range; HFNO, high-flow nasal oxygen; OSA, obstructive sleep apnea; SD, standard deviation; SoC, standard of care.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003ea\u003c/sup\u003e Wilcoxon rank-sum test \u003cem\u003eP\u003c/em\u003e value.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003eb\u003c/sup\u003e Fisher\u0026rsquo;s exact test \u003cem\u003eP\u003c/em\u003e value.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003eC\u003c/sup\u003e No statistical comparison.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eTOLDE and Number of Desaturation Episodes\u003c/h2\u003e \u003cp\u003eThe mean ToLDE time in the HFNO group was 0.34 minutes (median, 0 minutes; range, 0\u0026ndash;6.5 minutes), and the mean ToLDE in the SoC group was 0.97 minutes (median, 0 minutes; range: 0\u0026ndash;19.8 minutes; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.158; Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The distribution of ToLDE time was highly skewed because most patients (80%) failed to experience desaturation episodes.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eToLDE time, Length of PACU Observation, and BIS Episodes by Study Arm\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHFNO (N\u0026thinsp;=\u0026thinsp;50)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSoC (N\u0026thinsp;=\u0026thinsp;51)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTotal (N\u0026thinsp;=\u0026thinsp;101)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eToLDE time, min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.34 (1.16_\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.97 (3.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.66 (2.46)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0 (0.00\u0026ndash;0.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0 (0.00\u0026ndash;0.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.158\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0 (0.00\u0026ndash;0.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00\u0026ndash;6.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00\u0026ndash;19.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.00\u0026ndash;19.78\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal SpO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026le;\u0026thinsp;92% episodes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43 (86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38 (75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.514\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e81 (80)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6 (6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3 or more\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExperienced at least 1 SpO\u003csub\u003e2\u003c/sub\u003e \u0026le;92% episode, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43 (86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38 (74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.212\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e81 (80)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13 (26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20 (20)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMin SpO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003ec\u003c/sup\u003e, %\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90 (2.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e88.62 (3.91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e89.1 (3.55)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e91 (87.00\u0026ndash;92.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90 (84.00\u0026ndash;92.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.349\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e91 (85.50\u0026ndash;92.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e85.00\u0026ndash;92.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e81.00\u0026ndash;92.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e81.00\u0026ndash;92.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMax SpO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003ec\u003c/sup\u003e, %\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003en\u0026thinsp;=\u0026thinsp;13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eN\u0026thinsp;=\u0026thinsp;20\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e91.86 (0.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e90.38 (2.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e90.9 (2.45)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e92 (92.00\u0026ndash;92.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e92 (90.00\u0026ndash;92.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.203\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e92 (91.00\u0026ndash;92.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e91.00\u0026ndash;92.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e84.00\u0026ndash;92.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e84.00\u0026ndash;92.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLength of PACU observation\u003csup\u003ed\u003c/sup\u003e, min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.62 (17.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.39 (16.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e27.53 (17.23)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20 (12.25\u0026ndash;39.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26 (18.00\u0026ndash;44.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.076\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e23 (14.00\u0026ndash;41.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00\u0026ndash;60.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.00\u0026ndash;60.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.00\u0026ndash;60.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal BIS value \u0026ge;61 episodes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3 (3.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.69 (3.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.85 (3.53)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedian (IQR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (1.00\u0026ndash;4.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4 (2.00\u0026ndash;6.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.005\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3 (1.00\u0026ndash;5.00)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRange\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00\u0026ndash;15.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00\u0026ndash;19.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.00\u0026ndash;19.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eExperienced at least one BIS\u0026ge;61 episode, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10 (20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5 (10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.172\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e15 (15)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40 (80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e46 (90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e86 (85)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eAbbreviations: BIS, bispectral index; HFNO, high-flow nasal oxygen; IQR, interquartile range; Max, maximum; Min, minimum; PACU, post-anesthesia care unit; SD, standard deviation; SoC, standard of care; SpO\u003csub\u003e2\u003c/sub\u003e, oxygen saturation; ToLDE, total length of desaturation episode.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003ea\u003c/sup\u003e Wilcoxon rank-sum test \u003cem\u003eP\u003c/em\u003e value.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003eb\u003c/sup\u003e Fisher\u0026rsquo;s exact test \u003cem\u003eP\u003c/em\u003e value.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003ec\u003c/sup\u003e Of patients who experienced a desaturation episode.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003ed\u003c/sup\u003e Missing data for 1 patient in the SoC group.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eOf all 101 patients, 20 (20%) experienced at least one desaturation episode. In the HFNO group, 7 patients (14%; 95% CI, 6%\u0026ndash;27%) experienced at least one desaturation episode, and in the SoC group, 13 patients (26%; 95% CI, 14%\u0026ndash;40%) experienced at least one desaturation episode (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.212). Among the 20 patients experiencing desaturation episodes, ToLDE time ranged from approximately 1 second to 19.8 minutes (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Among the patients who experienced desaturation episodes, the mean ToLDE time was similar in the HFNO group (2.44 minutes; 95% CI, 0.36\u0026ndash;4.52 minutes) and in the SoC group (3.79 minutes; 95% CI, 0.35\u0026ndash;7.23 minutes).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eBIS Episodes and PACU Observation Time\u003c/h2\u003e \u003cp\u003eThe median total number of BIS episodes that a patient experienced was significantly higher for patients in the SoC group (4; range, 0\u0026ndash;19) than for patients in the HFNO group (2; range, 0\u0026ndash;15; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.005; Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The median length of PACU observation time was longer for patients in the SoC group (26 minutes; range, 5\u0026ndash;60 minutes) than patients in the HFNO group (20 minutes; range, 0\u0026ndash;60 minutes; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.076; Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003ePACU Self-Reported Symptoms\u003c/h2\u003e \u003cp\u003ePatients reported experiencing jaw pain, sore tongue, and dysphagia. In the SoC group, 8 complaints (16%) were reported: jaw pain (n\u0026thinsp;=\u0026thinsp;2; severe), sore tongue (n\u0026thinsp;=\u0026thinsp;2; moderate), and difficulty swallowing (n\u0026thinsp;=\u0026thinsp;4; mild). In the HFNO group, 6 complaints (12%) were reported: sore tongue (n\u0026thinsp;=\u0026thinsp;4; mild) and dysphagia (n\u0026thinsp;=\u0026thinsp;2; mild); no jaw pain was reported in this group. The proportion of patients reporting complaints was not significantly different between study arms (HFNO, 12%, vs. SoC, 16%; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.592). None of the patients in the study experienced dysphonia.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eAssociation between Patient Comorbidities and Desaturation Episodes\u003c/h2\u003e \u003cp\u003eAlthough the study arms were not significantly different with respect to OSA (HFNO, 56%, vs. SoC, 65%; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.419) or obesity (HFNO 50% vs. SoC 65%; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.161), both comorbidities were more prevalent in the SoC group. OSA, obesity, and other comorbidities and clinical characteristics are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Findings from univariable logistic regression to assess the independent associations between each comorbidity and desaturation episodes indicated that patients with obesity were 14% more likely to experience a desaturation episode (odds ratio [OR]\u0026thinsp;=\u0026thinsp;1.14; 95% CI, 0.42\u0026ndash;3.09; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.795) but patients with OSA were 24% less likely to experience a desaturation episode (OR\u0026thinsp;=\u0026thinsp;0.76; 95% CI, 0.28\u0026ndash;2.04; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.582). The multivariable model showed that using HFNO relative to SoC reduced the odds of desaturation by 54% (OR\u0026thinsp;=\u0026thinsp;0.46; 95% CI, 0.16\u0026ndash;1.30; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.143) after adjusting for obesity (OR\u0026thinsp;=\u0026thinsp;1.02; 95% CI, 0.37\u0026ndash;2.84; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.963) and OSA (OR\u0026thinsp;=\u0026thinsp;0.70; 95% CI, 0.26\u0026ndash;1.92; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.490).\u003c/p\u003e \u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eAlthough previous studies and meta-analyses indicated that HFNO significantly reduces the incidence and duration of hypoxic events in patients at risk of hypoxemia under deep sedation,\u003csup\u003e(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/sup\u003e our study found that using a HFNO at the rate of 70 L/min of 100% oxygen in patients who were obese or had obstructive sleep apnea (OSA) was not superior to using a standard non-rebreather to deliver 100% oxygen at a rate of 8 L/min in reducing airway-related adverse events. Specifically, there were no significant differences in the ToLDE (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.158) and the proportion of patients experiencing desaturation episodes (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.212) between the HFNO and SoC groups during interventional radiology procedures. These findings do not support our study hypothesis.\u003c/p\u003e \u003cp\u003eA previous multicenter study of 379 participants found that HFNO significantly reduced the incidence of desaturation episodes (SpO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026le;\u0026thinsp;92%) by 23.4% (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) in patients undergoing deep sedation for gastrointestinal endoscopies.\u003csup\u003e(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/sup\u003e However, our study did not observe similar outcomes, which may be attributed to differences in patient populations. Our study focused on patients with increased risks of airway obstruction, whereas the previous study included patients with various systemic comorbidities related to respiration and circulation. In our study, the median body mass index was 37.33 kg/m\u003csup\u003e2\u003c/sup\u003e (IQR, 33.74\u0026ndash;43.48 kg/m\u003csup\u003e2\u003c/sup\u003e), compared with 27 kg/m\u003csup\u003e2\u003c/sup\u003e (IQR, 23.9\u0026ndash;30.5 kg/m\u003csup\u003e2\u003c/sup\u003e) in the previous study. Additionally, our patients underwent interventional radiology procedures in a flat position, in contrast to the 15- to 30-degree upper body elevation used during the gastrointestinal endoscopies in the previous study; the flat position likely exacerbated the risk of airway obstruction and respiratory complications. The combination of a flat position and sedation in obese patients not only increases the risk of upper airway obstruction and overall respiratory workload but also exacerbates the respiratory mechanism by reducing the functional residual capacity and increasing the closing capacity of the lungs.\u003c/p\u003e \u003cp\u003eWhen the mouth is closed, HFNO provides approximately 1 cm H\u003csub\u003e2\u003c/sub\u003eO positive airway pressure per 10 L/min oxygen flow, reaching a maximum of 7 to 8 cm H\u003csub\u003e2\u003c/sub\u003eO at 70 L/min,\u003csup\u003e(8,9)\u003c/sup\u003e and is described as \u0026ldquo;dynamic, not set and not constant\u003csup\u003e\u0026rdquo;(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)\u003c/sup\u003e. However, maintaining a patent airway requires constant positive airway pressure above a critical level that varies between individuals.\u003csup\u003e(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)\u003c/sup\u003e In our study, 14% of patients in the HFNO group experienced desaturation episodes. This finding aligns with others from meta-analyses focused on obese patients,\u003csup\u003e(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/sup\u003e which suggests that although HFNO prolongs safe apnea, it does not significantly reduce hypoxic events. Another meta-analysis of 10 randomized controlled studies published between 2014 and 2021 (n\u0026thinsp;=\u0026thinsp;564; body mass index, 33\u0026ndash;52 kg/m\u003csup\u003e2\u003c/sup\u003e) demonstrated that use of HFNO prolonged safe apnea time but did not reduce hypoxic events.\u003csup\u003e(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/sup\u003e Further, Bright et al. conducted a meta-analysis and reported that use of a high-flow nasal cannula was not superior to use of a regular face mask in reducing hypoxic events (OR\u0026thinsp;=\u0026thinsp;0.49; 95% CI, 0.15\u0026ndash;1.63; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.24).\u003csup\u003e(14)\u003c/sup\u003e\u003c/p\u003e \u003cp\u003eAlthough our findings did not support our hypothesis, we identified some benefits of using HFNO in interventional radiology procedures, suggesting that further investigation of HFNO is warranted. These benefits included fewer episodes of a BIS value of 61 or above (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.005), shorter PACU stays (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.07), and fewer and less severe PACU self-reported symptoms in the HFNO group compared with the SoC group. Frequent episodes of BIS value 61 or above during total intravenous anesthesia typically indicate inadequate sedation levels.\u003c/p\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eStudy Limitations\u003c/h2\u003e \u003cp\u003eThis study has a few limitations. First, the electronic anesthesia record was incapable of capturing all the adverse events, the manual data collection in this study may have affected the preciseness of the data. Second, the study included both patients with obesities and patients with OSA. The underlying pathophysiologic and respiratory mechanisms of OSA and obesity are not the same, although airway obstruction is a primary feature in both conditions. For instance, the closing capacity and functional residual capacity are less affected in non-obese patients than in obese patients.\u003c/p\u003e \u003c/div\u003e"},{"header":"CONCLUSIONS","content":"\u003cp\u003eIn this pilot study, HFNO did not demonstrate superior improvement to the use of a standard non-rebreather oxygen delivery device in preventing hypoxic events among patients with increased risks of airway obstruction during interventional radiology procedures. However, HFNO may reduce the need for airway intervention and shorten postoperative recovery time, enhancing the overall patient experience. The observed effects were nonsignificant and inconclusive; further investigation is needed to determine their clinical significance.\u003c/p\u003e "},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eHFNO\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ehigh-flow nasal oxygen\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePACU\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003epostanesthesia care unit\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eOSA\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eobstructive sleep apnea\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSoC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003estandard-of-care\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eToLDE\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003etotal length of desaturation episodes\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eBIS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ebispectral index\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCONSORT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eConsolidated Standards of Reporting Trials\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eOR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eodds ratio\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003econfidence interval\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSpO\u003csub\u003e2\u003c/sub\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eperipheral oxygen saturation.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cul\u003e\n \u003cli\u003eEthics approval and consent to participate:This study was approved by the\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eInstitutional Review Board at The University of Texas MD Anderson Cancer Center (IRB2019-0348) and was registered in ClinicalTrials.gov (NCT04171037) and in the Clinical Trials Reporting Program database (NCI-2019-07291).\u0026nbsp;\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eAll patients provided a signed informed consent.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eData Availability: Availability of data and materials are limited in the report and analysis.\u003c/li\u003e\n \u003cli\u003eFunding Statement: The University of Texas MD Anderson Cancer Center and the National Cancer Institute provided the primary sponsorship for this study. Fisher \u0026amp; Paykel Healthcare (New Zealand) provided funding support.\u003c/li\u003e\n \u003cli\u003eConflicts of Interest: This study received funding support from Fisher \u0026amp; Paykel Healthcare (New Zealand).\u003c/li\u003e\n \u003cli\u003eAuthors' contributions: 1.\u0026nbsp;Gang Zheng, this author helped with the development of the study protocol, data verification, and writing manuscript. 2. Mike Hernandez, this author helped with the development of the study protocol, data analysis and writing manuscript. 3. Carin Hagberg, this author helped with the development of the study protocol, manuscript editing and finalization of the article.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cul\u003e\n \u003cli\u003eAcknowledgements: The authors of this article would like to acknowledge the contributions of Ms. Raven Bailey, BS, Mr. Tyrone Burnett Jr., BS, and Mr. Tariq A. Syed, MS, who were the Senior Clinical Study Coordinators in the Division of Anesthesiology, Pain Management and Critical Care at The University of Texas MD Anderson Cancer Center, Houston, Texas, USA. Both Mr. Burnett and Mr. Syed helped with the protocol development and documentation, and Ms. Bailey helped with data collection and data organization. We thank Madison Semro, Associate Scientific Editor, and Stephanie Deming, Senior Scientific Editor, in the Research Medical Library at The University of Texas MD Anderson Cancer Center for editing this article. We also acknowledge the sponsorship of MD Anderson and the National Cancer Institute and the funding support of Fisher \u0026amp; Paykel Healthcare (New Zealand)\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eWong DT, Dallaire A, Singh KP, et al. High-flow nasal oxygen improves safe apnea time in morbidly obese patients undergoing general anesthesia a randomized controlled trial. Anesth Analg. 2019;129(4):1130\u0026ndash;36.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchutzer-Weissmann J, Wojcikiewicz T, Karmali A, et al. Apnoeic oxygenation on morbid obesity: a randomized controlled trial comparing facemask and high-flow nasal oxygen delivery. Br J Anaesth. 2023;130(1):103\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePatel A, Nouraei SAR. Transnasal humidified rapid insufflation ventilatory exchange (THRIVE): a physiological method of increasing apnoea time in patients with difficult airways. Anaesthesia. 2015;70(3):323\u0026ndash;29.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRitchie JE, Williams AB, Gerard C, Hockey H. Evaluation of a humidified nasal high-flow oxygen system, using oxygraphy, capnography and measurement of upper airway pressure. Anaesth Intensive Care. 2011;39(6):1103\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGroves N, Tobin A. High flow nasal oxygen generates positive airway pressure in adult volunteers. Aust Crit Care. 2007;20(4):126\u0026ndash;31.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eThiruvenkatarajan V, Sekhar V, Wong DT, Currie J, Wijk RV, Ludbrook GL. Effect of high-flow nasal oxygen on hypoxaemia during procedural sedation: a systematic review and meta-analysis. Anaesthesia. 2023;78(1):81\u0026ndash;92.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNay MA, Fromont L, Eugene A, et al. High flow nasal oxygenation or standard oxygenation for gastrointestinal endoscopy with sedation in patients at risk of hypoxaemia: a multicentre randomized controlled trial (ODEPHI trial). Br J Anaesth. 2021;127(1):133\u0026ndash;42.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParke RL, Bloch A, McGuinness SP. Effect of very high flow nasal therapy on airway pressure and end expiratory lung impedance in healthy volunteers. Respir Care. 2015;60(10):1397\u0026ndash;430.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVieira F, Bezerra FS, Coudroy R, et al. High-flow nasal cannula compared with continuous positive airway pressure: a bench and physiological study. J Appl Phys. 2022;132:1580\u0026ndash;90.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFisher \u0026amp; Paykel Healthcare. Accessed Nov 6, 2023. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.fphcare.com\u003c/span\u003e\u003cspan address=\"https://www.fphcare.com\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSullivan CE, Berthon-Jones M, Issa FG. Nocturnal nasal-airway pressure for sleep apnea. N Engl J Med. 1983;309(2):112.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuy L, Christensen R, Dodd B, et al. The effect of transnasal humidified rapid-insufflation ventilator exchange (THRIVE) versus nasal prongs on safe apnoea time in paralysed obese patients: a randomized controlled trial. Br J Anaesth. 2022;128(2):375\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHung KC, Ko CC, Chang PC, et al. Efficacy of high-flow nasal oxygenation against peri-and post-procedural hypoxemia in patients with obesity: a meta-analysis of randomized controlled trials. Sci Rep. 2022;12(1):6448.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBright MR, Harley WA, Velli G, Zahir SF, Eley V. High-flow nasal cannula for apneic oxygenation in obese patients for elective surgery: a systematic review and meta-analysis. Anesth Analg. 2023;136(3):483\u0026ndash;93.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-anesthesiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bane","sideBox":"Learn more about [BMC Anesthesiology](http://bmcanesthesiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bane","title":"BMC Anesthesiology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8165967/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8165967/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eThe room configuration in interventional radiology procedures hinders simultaneous access to the patient\u0026rsquo;s airway and anesthesia machines, and this issue may lead to suboptimal sedation levels in patients with increased risks of airway obstruction owing to patient safety concern. We conducted a randomized trial to evaluate the effectiveness of using a high-flow nasal oxygen (HFNO) device (F\u0026amp;P Optiflow\u0026trade;) versus a standard non-rebreather oxygen delivery device to reduce airway obstruction and improve patient outcomes during anesthesia among patients with increased risks of airway obstruction.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003ePatients at increased risks of airway obstruction were randomized to receive 100% oxygen at a rate of either 70 L/min (HFNO group) or 8 L/min (standard-of-care [SoC] group) along with a continuous intravenous propofol infusion to achieve unconsciousness. We evaluated the total length of desaturation episodes [ToLDE] defined as oxygen saturation [SpO\u003csub\u003e2\u003c/sub\u003e] \u0026le;92%, the number of desaturation episodes, and the time spent in the postanesthesia care unit (PACU). The level of sedation was assessed using the number of bispectral index (BIS) episodes (defined as episodes of BIS value\u0026thinsp;\u0026ge;\u0026thinsp;61), and patients\u0026rsquo; PACU self-reported symptoms.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe study included 101 patients, 50 in the HFNO group and 51 in the SoC group. The mean ToLDE time was 0.34 minutes (median, 0; range 0-6.5 minutes) in the HFNO group and 0.97 minutes (median, 0; range 0-19.8 minutes) in the SoC group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.158). The proportion of patients experiencing at least one desaturation episode was 14% in the HFNO group and 26% in the SoC group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.212). The median total number of BIS episodes was higher in the SoC group (4; range, 0\u0026ndash;19) than the HFNO group (2; range, 0\u0026ndash;15; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.005). Median PACU stay was 20 minutes (range, 0\u0026ndash;60) in the HFNO group and 26 minutes (range, 5\u0026ndash;60) in the SOC group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.076). Six of 50 patients (12%) in the HFNO group and 8 of 51 (16%) in the SoC group reported PACU complaints and the complaints were less severe in the HFNO group.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eHFNO was not superior to a standard non-rebreather oxygen delivery device in preventing hypoxic events among patients with increased risks of airway obstruction undergoing moderate to deep sedation. However, HFNO may reduce the need for airway interventions and improve the overall patient experience and thus warrants further investigation.\u003c/p\u003e\u003ch2\u003eTrial registration:\u003c/h2\u003e \u003cp\u003eClinicalTrials.gov ID: NCT04171037; Date of original registration: November 19, 2019; This study was retrospectively registered. Study principal investigator: Gang Zheng; This manuscript adheres to the applicable Consolidated Standards of Reporting Trials (CONSORT) guidelines.\u003c/p\u003e","manuscriptTitle":"Use of Optiflow THRIVE High-Flow Nasal Oxygen System versus a Non-rebreather Oxygen Delivery Device in Patients with Increased Risks of Airway Obstruction in Interventional Radiology Procedures: A Randomized Pilot Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-22 09:38:02","doi":"10.21203/rs.3.rs-8165967/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-02T11:41:07+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-22T08:49:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"230324499242644548118836994365505291521","date":"2026-02-19T12:01:15+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-17T19:25:02+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"202319484600529715116617356374004459390","date":"2026-02-06T10:50:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"132623038470702628712443721562791727805","date":"2026-02-05T17:57:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"227348276818742714351072561642250949169","date":"2025-12-19T16:04:20+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-12-16T07:56:17+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-08T05:29:03+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-05T15:27:49+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-04T17:31:59+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Anesthesiology","date":"2025-12-04T17:23:18+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-anesthesiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bane","sideBox":"Learn more about [BMC Anesthesiology](http://bmcanesthesiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bane","title":"BMC Anesthesiology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3d60499d-2e4e-48ac-94be-8624879128c1","owner":[],"postedDate":"December 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-06T12:25:32+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-22 09:38:02","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8165967","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8165967","identity":"rs-8165967","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}