Comparison of high flow nasal cannula oxygen therapy versus nasal cannula in sedated transesophageal echocardiography in patients with mitral regurgitation: a prospective, randomized controlled clinical trial

Comparison of high flow nasal cannula oxygen therapy versus nasal cannula in sedated transesophageal echocardiography in patients with mitral regurgitation: a prospective, randomized controlled clinical trial | 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 Comparison of high flow nasal cannula oxygen therapy versus nasal cannula in sedated transesophageal echocardiography in patients with mitral regurgitation: a prospective, randomized controlled clinical trial Wanlin Li, Ziqi Qiu, Wenwen Zhang, Yajie Xu, Zhaojing Fang, Xiaoliang Wang, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4055954/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Hypoxia is common among mitral regurgitation patients and may be more susceptible to anesthetics. To evaluate the security and efficacy of high flow nasal cannula oxygen therapy (HFNC) and nasal cannula for sedated transesophageal echocardiography (TEE) in patients with mitral regurgitation. Methods 226 patients scheduled to receive TEE under sedation were randomized into two groups: HFNC group (Group H) and nasal cannula group (Group C). The incidence of hypoxia during the TEE procedure was the main result. Secondary outcomes included hypoxia-related measures and interventions, ventilation and adverse events related to sedation. Results In comparison to Group C, Group H exhibited a significant decrease in the incidences of hypoxia and severe hypoxia, dropping from 26.3–15.0% ( P < 0.05) and 1.8–0% ( P < 0.05), respectively. Conclusion Compared with nasal cannula, HFNC can reduce hypoxia during TEE procedure in patients with mitral regurgitation. Trial registration ChiCTR2300068412, 17/02/2023. High flow nasal cannula Transesophageal echocardiography Sedation Hypoxia Figures Figure 1 Background It is recognized that the most common valve heart disease is mitral regurgitation (MR). In China, the population of individuals with MR at a Grade III level or higher exceeds 10 million, necessitating therapeutic interventions[ 1 , 2 ]. Surgical valve repair or replacement is considered the standard method to treat MR and has been proven to relieve patients' symptoms and prolong their survival time. However, 50% of MR patients do not receive effective treatment because of high-risk factors such as low cardiac function, multiple comorbidities, and advanced age, which are not suitable for surgery [ 3 ]. For patients deemed too old, too sick, or too risky for conventional open-heart surgery, the MitraClip is a viable therapy option [ 4 ]. Before undergoing TEER, echocardiography serves as a crucial technique for selecting patients in order to evaluate cardiac and valve function using the EVEREST criteria. [ 5 ]. To alleviate patients' apprehension, anxiety, and fear related to TEE and mitigate potential discomfort, adverse reactions, and complications arising from the esophageal ultrasonography probe's insertion into the esophagus through the pharynx, sedation is commonly administered during TEE procedures. The conventional nasal cannula employed for TEE under deep sedation is limited to delivering oxygen flow rates within the range of 2–8 L/min [ 6 ]. Given that a substantial percentage of patients receiving TEE are elderly and exhibit compromised cardiopulmonary function with diminished oxygen reserves, they tend to be more susceptible to anesthetics and are at an increased risk of respiratory depression. This heightened vulnerability elevates the likelihood of perioperative hypoxemia [ 7 ]. Consequently, ensuring optimal oxygenation throughout the examination emerges as a critical challenge for anesthesiologists. High-flow nasal cannula (HFNC) can provide warmed and moistened gas with a high flow rate and 100% concentration of oxygen [ 8 , 9 ]. A growing number of patients receiving procedural sedation and analgesia rely on oxygen delivered via HFNC [ 10 ]. To validate HFNC in various procedural sedations, randomized controlled trials have been carried out, including gastrointestinal endoscopy, bronchoscopy, endoscopic retrograde cholangiopancreatography, and atrial fibrillation catheter ablation [ 11 – 14 ]. Currently, there is no study comparing the use of HFNC and nasal cannula during sedated TEE. This research seeks to assess the efficacy of HFNC application in sedated TEE and provide relevant evidence for clinical practice. Methods Study Design This single-blind, prospective, randomized controlled trial received approval from the institutional review board of Nanjing First Hospital (KY20230116-08) and was pre-registered in the Chinese Clinical Trial Registry(ChiCTR2300068412, principal investigator: J. Gu, MD, PhD, date of registration: February 17, 2023), which can be reached at https://www.chictr.org.cn/showproj.html?proj=190434 . The research was carried out strictly in compliance with the Declaration of Helsinki and Good Clinical Practice guidelines and followed the consolidated Standards of Reporting Trials (CONSORT) guidelines. Written informed consent was obtained from all patients. Participants In this research, patients planned for a propofol-sedated TEE were recruited. The following were the inclusion criteria: (1) ≥ 18 years old; (2) BMI < 30 kg/m2; (3) Planned mitra-clip surgery. The following were the exclusion criteria: (1) Coagulation disorders or tendency to nosebleeds; (2) Patients at high risk of reflux aspiration; (3) Acute arrhythmia accompanied by hemodynamic instability. hemodynamic instability; (4) History of intubation difficulties. Randomization and blinding Each patient was randomly allocated to either the HFNC group (Group H) or the nasal cannula oxygen group (Group C) at a 1:1 ratio, using computer randomization software (SPSS 21.0). Blinded to the randomization grouping, an investigator registered and assigned participants. The randomization code was stored in a sealed opaque envelope, accessible solely to the researchers and opened prior to anesthesia induction. Postoperatively, patients were interviewed by team members who were not conscious of the randomization grouping, a team member registered and assigned participants. Interventions and anesthesia After the patients entered the room, electrocardiogram, respiration, blood pressure and peripheral oxygen saturation (SpO 2 ) were monitored, and they were instructed to assume a supine position on their right side. Group C received 2 L/min of pure oxygen through nasal intubation, while HFNC group utilized HFNC (Fisher & Paykel, Panmure, New Zealand) for oxygen inhalation (30 L/min, FiO 2 = 100%). In both groups, patients breathed calmly for 3 minutes, undergoing denitrification and oxygenation. Subsequently, the initial loading dose of propofol (0.5-1.0 mg/kg) was slowly injected intravenously. Once the patient's eyelash reflex disappeared, Group C continued to breathe pure oxygen through nasal cannula (2 L/min), while HFNC group adjusted the oxygen flow to 60 L/min. The esophageal probe insertion occurred when the Ramsay score was > 4 (indicating slow or no response to glabella tapping or loud auditory stimulation). Continuous monitoring and maintenance of Ramsay score > 4 were ensured throughout the examination. During the procedure, the infusion rate of propofol was maintained at 25–75 µg/kg/min and the total dosage was documented. Hypoxia in the peri-examination phase was managed through the following measures: (1) discontinue the medication and arouse the patient; (2) lift the jaw and increase the flow rate of oxygen; (3) withdraw the endoscope and initiate mask ventilation simultaneously; (4) endotracheal intubation. In cases of identified hypotension during evaluation, intravenous injection of ephedrine at a dose of 5–10 mg was administered. If the heartbeat fell below 50 beats per minute, 0.25–0.50 mg atropine was initiated. Outcomes and data collection The main outcome was the incidence of hypoxia (75% ≤ SpO 2 < 90% for < 60 s) during anesthesia [ 14 – 16 ]. The following were secondary outcomes: (1) hypoxia: subclinical respiratory depression (90% ≤ SpO 2 < 95%); severe hypoxia (SpO 2 < 75% for any duration or 75% ≤ SpO 2 < 90% for ≥ 60 s); (2) Treatments for hypoxia ; (3) adverse events regarding HFNC within 30 min after TEE inspection (airway injury, pneumothorax, subcutaneous emphysema); (4) sedation-related adverse events (nausea/vomiting, reflux, sore throat, dyspnea, tract obstruction or asphyxia) [ 17 , 18 ]; (5) general information during TEE: mean arterial pressure (MAP), lowest MAP, lowest systolic blood pressure, vasoactive medication use, dosage of propofol and examination time; (6) doctors’ and Patients’ satisfaction with examination were also investigated by a 5- point Likert-type scale. Sample size The estimated difference in the incidence of hypoxia between the two groups was employed to calculate the sample size using PASS software (version 15.0; NCSS, LLC). According to our previous research, we observed that 30% of hypoxic incidents occurred during TEE. Anticipating an improvement in patient outcomes, we project that the implementation of HFNC is expected to reduce the rate to 15%. Based on a power of 80% and an α of 5%, a degree of freedom of 1 and factoring in a conservative attrition rate of 10%, our meticulous calculations indicated that 226 patients would be required. Statistical analysis To perform the statistical analysis, SPSS software (21.0, Inc., Chicago, IL, USA) was utilized. For every continuous variable, we conducted Levene's and Shapiro-Wilk tests. The statistics are shown as means ± standard deviations or median [25th and 75th percentiles] based on the test results. One-way ANOVA was carried out to evaluate the normally distributed measurement data (dosage of propofol) between groups, and pairwise comparisons were performed using the LSD method. The rank sum test was used to compare measurement data with skewed distributions (SpO 2 , duration, median 1 min after anesthetic induction, wake-up time) between groups. Dunn's method was applied for multiple comparisons. By applying a chi-square test or Fisher's exact test, we contrasted the frequency of hypoxia and sedation-related adverse events between the groups. The Boferroni method was used to adjust the P value of the pairwise comparison. At P < 0.05, statistical significance was established. Results After enrollment, 226 patients were randomly assigned to two groups from February 2023 to January 2024 (Fig. 1 ). In Group C, there were three patients who withdrew from the trial due to the incorrect collection of data. A comprehensive analysis was conducted on a total of 223 patients. There were no statistically significant variations found in the airway assessment indicators and baseline characteristics between the two groups ( P > 0.05) (Table 1 ). TEE time, propofol dosage, and hemodynamic index within the two groups were no different ( P > 0.05) (Table 2 ). Table 1 Baseline characteristics of the study participants Variables Group C(n = 110) Group H (n = 113) P value Age (years) 72.3 ± 11 70.7 ± 12 0.30 Sex (male/female) 81/29 79/34 0.54 Body mass index (kg/m 2 ) 22.4 ± 4.3 21.8 ± 3.6 0.26 ASA grade (III/IV) 102/8 107/6 0.55 Mallampati class ( I/II/III/IV) 49/54/6/1 52/48/11/2 0.53 Mouth opening (1/2/3) 2/5/103 3/3/107 0.69 Thyromental distance(I/II/III) 98/12/0 94/18/1 0.33 History of hypertension 90(81.8) 86(76.8) 0.30 History of diabetes mellitus 40(36.0) 39(34.5) 0.77 LV ejection fraction (%) 34.2 ± 8.1 33.3 ± 7.7 0.40 PA pressure greater than 40 48 (15.8) 52 (17.0) 0.72 Baseline SpO 2 (%) 97 (97, 99) 98 (97, 98) 0.56 Data are presented as mean ± standard deviations, a number of patients, number (%), or median (Q1, Q3). Abbreviations: ASA, American Society Anaesthesiologists. LV: left ventricle. Group C: nasal catheter oxygen group, Group H: HFNC group. Table 2 Data of TEE Group C (n = 110) Group H (n = 113) P value Duration, min 15.3 ± 3.2 16.1 ± 3.8 0.09 Dose of propofol, mg 92.5 ± 15.3 95.3 ± 12.8 0.14 Hypotension (MAP < 60 mmHg) 27 (24.5) 26 (23.0) 0.79 Lowest mean arterial pressure ≥100–120 mmHg 5(4.5) 5(4.4) 0.96 ≥80 < 100 mmHg 30(27.3) 33(29.2) 0.75 ≥60–80 mmHg 48(43.6) 49(43.4) 0.97 < 60 mmHg 27 (24.5) 26 (23.0) 0.79 Lowest systolic blood pressure ≥100–120 mmHg 43(38.1) 47(41.6) 0.70 ≥ 80 < 100 mmHg 42(38.2) 48(42.5) 0.51 ≥60–80 mmHg 24(21.8) 18(15.9) 0.26 < 60 mmHg 1(0.9) 0(0) 0.49 Vasoactive medication use 27 (24.5) 25 (22.1) 0.67 Data are presented as mean ± SD and median (Q1, Q3). In comparison to nasal cannula oxygen, the utilization of HFNC demonstrated a significant reduction in the incidences of hypoxia and severe hypoxia, going from 26.3–15.0% ( P < 0.05) and 1.8–0% ( P < 0.05), respectively (Table 3 ). Table 3 Respiratory-related adverse events and intervention Group C (n = 110) Group H (n = 113) P value Total events 64(58.2) 37 (32.7) 0.000 Subclinical respiratory depression 33(30.0) 20(15.0) 0.03 hypoxia 29(26.3) 17 (15.0) 0.04 Severe hypoxia 2(1.8) 0(0) 0.24 Jaw lift 37(33.6) 22(19.4) 0.02 Mask ventilation 13(11.8) 0(0) 0.000 Mechanical ventilation for endotracheal intubation 1(0.9) 0(0) 0.49 Data are presented as a number of patients, number (%), or median (Q1, Q3). In Group H, a significant reduction was observed in the frequency of hypoxia, the necessity for jaw lift maneuvers, and the reliance on mask ventilation for managing hypoxia-related adverse events ( P < 0.05), as shown in Table 3 . A patient in Group C experienced respiratory arrest. Immediate rescue measures, including tracheal intubation, were implemented. Subsequently, the individual was transferred to the cardiology intensive care unit for further treatment before safely discharge. Group H saw a lower occurrence of choking and paradoxical response compared with Group C ( P < 0.05) (Table 4 ). The satisfaction scores of operators and anesthesiologists in group H were higher than those in group C ( P < 0.05) (Table 5 ). After patients were awakened, adverse events associated with HFNC breathing were noted 5 min and 30 min later. Pneumatic and airway injuries were not discovered in any of the patients. Table 4 Sedation-related adverse events Group C (n = 110) Group H (n = 113) P value Paradoxical response 11(10) 3(2.7) 0.03 Reflux 0(0) 0(0) 1.0 Nausea/vomit 0(0) 0(0) 1.0 Airway obstruction 0(0) 0(0) 1.0 Choking 11(10) 3(2.7) 0.03 Data are presented as a number of patients, number (%), or median (Q1, Q3). Table 5 Likert satisfaction scores of patients, operators and anesthesiologists Group C (n = 110) Group H (n = 113) P value patients 4(3, 4) 4(3, 4) 0.26 operators 3(3, 4) 4(4, 5) 0.00 anesthesiologists 3(3, 4) 5(4, 5) 0.00 Data are presented as a number of patients, median (Q1, Q3). Discussion In our study, HFNC reduced the incidence of hypoxia during TEE from 26.3–15.0% when compared to nasal cannula. In Group C, one patient suffered respiratory arrest and was sent to the cardiology intensive care unit for further treatment. However, there were no patients with severe hypoxia requiring tracheal intubation in Group H. In Group H, the low occurrence of hypoxia allowed the surgeon to proceed without waiting for the anesthesiologist to address it, resulting in a more uninterrupted operation. The satisfaction levels of both the surgeon and anesthesiologist were higher in Group H. This study found a higher incidence of hypoxia than Cooper B. Kersey's study, possibly because the patients in this study planned Mitraclip procedures [ 19 ]. These individuals (low ejection fraction and pulmonary hypertension) might become more vulnerable to hypoxia and hemodynamic instability. HFNC reduces dead space, elevates functional residual volume and positive end-expiratory pressure, while concurrently enhancing inspired oxygen levels [ 20 ]. It has been shown in multiple studies that HFNC can improve patient oxygenation and comfort after gastrointestinal endoscopy, respiratory tract infections, and extubation. Nevertheless, few studies have been conducted on patients at high risk of cardiogenic hypoxia [ 14 , 21 ]. MR can adversely affect exercise tolerance and heighten susceptibility to hypoxia through various mechanisms. The backflow of blood into the left atrium during systole elevates pressure in the pulmonary circulation, inducing pulmonary congestion and edema. This scenario hampers gas exchange in the lungs, subsequently impairing the oxygenation of blood. Furthermore, the heightened workload on the heart can result in left ventricular dysfunction, exacerbating the reduction in exercise tolerance and increasing vulnerability to hypoxia. HFNC diminishes intrapulmonary shunting and imparts a specific level of positive end-expiratory pressure, causing an elevation in intrathoracic pressure. Consequently, this results in a partial collapse of the patient's inferior vena cava during inspiration, leading to a reduction in preload [ 22 , 23 ]. In cases of cardiogenic pulmonary edema, HFNC proves beneficial in maintaining adequate oxygenation by augmenting respiratory load and facilitating efficient gas exchange [ 24 , 25 ]. The outcomes of this study align with those reported in previous research [ 22 – 26 ]. This study has several limitations: (1) Divergent Definitions of Hypoxia: The study faced challenges due to variations in the definitions of hypoxia, leading to notable differences in the specified range and duration of SpO2 within these definitions. Consequently, the statistical data may not accurately reflect the specific distinctions in hypoxia incidence compared to previous studies; (2) Inadequate Monitoring of End-Expiratory Carbon Dioxide under HFNC: At higher oxygen flow rates with HFNC, there was a difficulty in accurately monitoring end-expiratory carbon dioxide levels. Due to limitations in hospital funding, blood carbon dioxide levels were not measured, potentially affecting the comprehensive assessment of respiratory parameters in these conditions. Conclusion This study found that compared with nasal cannula, HFNC can lessen hypoxia during TEE examinations in MR patients. Abbreviations ASA American Society of Anesthesiologists CONSORT Consolidated Standards of Reporting Trials HFNC High flow nasal cannula oxygen therapy LV left ventricle MAP mean arterial pressure MR mitral regurgitation; SD standard deviation SpO 2 peripheral oxygen saturation TEE transesophageal echocardiography Declarations Ethics approval and consent to participate This single-blind, prospective, randomized controlled trial received approval from the institutional review board of Nanjing First Hospital (KY20230116-08) and was pre-registered in the Chinese Clinical Trial Registry (ChiCTR2300068412, principal investigator: J. Gu, MD, PhD, date of registration: 17/02/2023). The research was carried out strictly in compliance with the Declaration of Helsinki and Good Clinical Practice guidelines and followed the CONSORT guidelines. Written informed consent was obtained from all patients. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Availability of data and materials The datasets generated and/or analyzed during the current study are not publicly available due to policy issues in the hospital but are available from the corresponding author on reasonable request. Acknowledgements Not applicable. Authors' contributions Wanlin Li, Ziqi Qiu and Hongwei Shi designed the study. Yajie Xu and Zhaojing Fang recuited patients. Wenwen Zhang, Meirong Ling and Xiaoliang Wang conducted statistical analysis. Wanlin Li, Ziqi Qiu , Meirong Ling and Yong Zhang wrote the manuscript. The final version of the manuscript was read and approved by all authors. References Li J, Pan W, Yin Y, et al. Prevalence and correlates of mitral regurgitation in the current era: an echocardiography study of a Chinese patient population[J]. Acta Cardiol. 2016;71(1):55–60. Hu P, Liu XB, Liang J, et al. A hospital-based survey of patients with severe valvular heart disease in China[J]. Int J Cardiol. 2017;231:244–7. Head SJ, van Leeuwen WJ, Van Mieghem NM, Kappetein AP. Surgical or transcatheter mitral valve intervention: complex disease requires complex decisions. EuroIntervention. 2014;9(10):1133–5. Kataoka A, Watanabe Y, OCEAN-SHD Family. MitraClip: a review of its current status and future perspectives. Cardiovasc Interv Ther. 2023;38(1):28–38. Hahn RT, Saric M, Faletra FF, Garg R, Gillam LD, Horton K, et al. Recommended standards for the performance of transesoph-ageal echocardiographic screening for structural heart intervention: from the American Society of Echocardiography. J Am Soc Echocardiogr. 2022;35:1–76. Hsu WC, Orr J, Lin SP, et al. Efficiency of oxygen delivery through different oxygen entrainment devices during sedation under low oxygen flow rate: a bench study. J Clin Monit Comput. 2018;32(3):519–25. Qadeer MA, Rocio Lopez A, Dumot JA, et al. Risk factors for hypoxemia during ambulatory gastrointestinal endoscopy in ASA I-II patients. Dig Dis Sci. 2009;54(5):1035–40. Lodeserto FJ, Lettich TM, Rezaie SR. High-flow Nasal Cannula: Mechanisms of Action and Adult and Pediatric Indications. Cureus. 2018;10(11):e3639. Hernández G, Roca O, Colinas L. High-flow nasal cannula support therapy: new insights and improving performance. Crit Care. 2017;21(1):62. Drake MG, High-Flow. Nasal Cannula Oxygen in Adults: An Evidence-based Assessment. Ann Am Thorac Soc. 2018;15(2):145–55. Homberg MC, Bouman EA, Linz D, et al. High-flow nasal cannula versus standard low-flow nasal cannula during deep sedation in patients undergoing radiofrequency atrial fibrillation catheter ablation: a single-centre randomised controlled trial. Trials. 2022;23(1):378. Longhini F, Pelaia C, Garofalo E, et al. High-flow nasal cannula oxygen therapy for outpatients undergoing flexible bronchoscopy: a randomised controlled trial. Thorax. 2022;77(1):58–64. Lee MJ, Cha B, Park JS, et al. Impact of High-Flow Nasal Cannula Oxygenation on the Prevention of Hypoxia During Endoscopic Retrograde Cholangiopancreatography in Elderly Patients: A Randomized Clinical Trial. Dig Dis Sci. 2022;67(8):4154–60. Lin Y, Zhang X, Li L, et al. High-flow nasal cannula oxygen therapy and hypoxia during gastroscopy with propofol sedation: a randomized multicenter clinical trial. Gastrointest Endosc. 2019;90(4):591–601. Riccio CA, Sarmiento S, Minhajuddin A, et al. High-flow versus standard nasal cannula in morbidly obese patients during colonoscopy: A prospective, randomized clinical trial. J Clin Anesth. 2019;54:19–24. Thiruvenkatarajan V, Dharmalingam A, Arenas G, et al. Effect of high-flow vs. low-flow nasal plus mouthguard oxygen therapy on hypoxaemia during sedation: a multicentre randomised controlled trial. Anaesthesia. 2022;77(1):46–53. Mason KP, Green SM, Piacevoli Q. Adverse event reporting tool to standardize the reporting and tracking of adverse events during procedural sedation: a consensus document from the World SIVA International Sedation Task Force. Br J Anaesth. 2012;108(1):13–20. Yang ZY, Meng Q, Xu YH, et al. Supraglottic jet oxygenation and ventilation during colonoscopy under monitored anesthesia care: a controlled randomized clinical trial. Eur Rev Med Pharmacol Sci. 2016;20(6):1168–73. Kersey CB, Lele AV, Johnson MN, Pattock AM, Liu L, Huang GS, Kirkpatrick JN, Mazimba S, Jobarteh S, Kwon Y. The Quality and Safety of Sedation and Monitoring in Adults Undergoing Nonoperative Transesophageal Echocardiography. Am J Cardiol. 2023;194:40–5. Parke R, McGuinness S, Eccleston M. Nasal high-flow therapy delivers low-level positive airway pressure. Br J Anaesth. 2009;103:886–90. Homberg MC, Bouman EA, Linz D, et al. High-flow nasal cannula versus standard low-flow nasal cannula during deep sedation in patients undergoing radiofrequency atrial fibrillation catheter ablation: a single-centre randomised controlled trial. Trials. 2022;23(1):378. Ko DR, Beom J, Lee HS, You JS, Chung HS, Chung SP. Benefits of high-flow nasal cannula therapy for acute pulmonary edema in patients with heart failure in the emergency department: a prospective multi-center randomized controlled trial. J Clin Med. 2020;21:1937. Makdee O, Monsomboon A, Surabenjawong U, et al. High-Flow Nasal Cannula Versus Conventional Oxygen Therapy in Emergency Department Patients With Cardiogenic Pulmonary Edema: A Randomized Controlled Trial. Ann Emerg Med. 2017;70(4):465–72. Kang MG, Kim K, Ju S, Park HW, Lee SJ, Koh JS, Hwang SJ, Hwang JY, Bae JS, Ahn JH, Jang JY, Park Y, Jeong YH, Kwak CH, Park JR. Clinical efficacy of high-flow oxygen therapy through nasal cannula in patients with acute heart failure. J Thorac Dis. 2019;11(2):410–7. Fraser JF, Spooner AJ, Dunster KR, Anstey CM, Corley A. Nasal high flow oxygen therapy in patients with COPD reduces respiratory rate and tissue carbon dioxide while increasing tidal and end-expiratory lung volumes: a randomised crossover trial. Thorax. 2016;71(8):759–61. Schwabbauer N, Berg B, Blumenstock G, Haap M, Hetzel J, Riessen R. Nasal high-flow oxygen therapy in patients with hypoxic respiratory failure: effect on functional and subjective respiratory parameters compared to conventional oxygen therapy and non-invasive ventilation (NIV). BMC Anesthesiol. 2014;14:66. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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-4055954","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":281572308,"identity":"e2dd2c15-144e-4a4b-8ec8-7b7087ad977d","order_by":0,"name":"Wanlin Li","email":"","orcid":"","institution":"Nanjing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Wanlin","middleName":"","lastName":"Li","suffix":""},{"id":281572309,"identity":"aca330d0-5784-4c7b-963b-8668a087beb0","order_by":1,"name":"Ziqi Qiu","email":"","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Ziqi","middleName":"","lastName":"Qiu","suffix":""},{"id":281572310,"identity":"60c44363-cd6c-4d99-b315-2582e44f38d7","order_by":2,"name":"Wenwen Zhang","email":"","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Wenwen","middleName":"","lastName":"Zhang","suffix":""},{"id":281572311,"identity":"3a58da1b-b708-46ce-b527-34d36b8f31a5","order_by":3,"name":"Yajie Xu","email":"","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yajie","middleName":"","lastName":"Xu","suffix":""},{"id":281572312,"identity":"c7d80902-8f15-4b5c-9e93-27efd9c7a569","order_by":4,"name":"Zhaojing Fang","email":"","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Zhaojing","middleName":"","lastName":"Fang","suffix":""},{"id":281572313,"identity":"e35d659b-ebc1-4e05-8bc4-8b5dc8d1ce27","order_by":5,"name":"Xiaoliang Wang","email":"","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Xiaoliang","middleName":"","lastName":"Wang","suffix":""},{"id":281572314,"identity":"0b2ff0c3-d9bd-42bc-b846-27522f760749","order_by":6,"name":"Yong Zhang","email":"","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yong","middleName":"","lastName":"Zhang","suffix":""},{"id":281572315,"identity":"d9f1e869-08c0-42bf-bdcb-7e15f65117c7","order_by":7,"name":"Meirong Ling","email":"","orcid":"","institution":"Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Meirong","middleName":"","lastName":"Ling","suffix":""},{"id":281572316,"identity":"8dcf03ec-7c47-4acb-9fc8-a1abed36e41c","order_by":8,"name":"Hongwei Shi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAnElEQVRIiWNgGAWjYFCCBDYGhgoJOXkStZyxMDZsIEkLY1tFIsMBYjXotqc/e8w7TyKBsYH54aMbxGgxO/PG3Jh3m0QeOwObsXEOUVpu5LBJ526TKGZs4GGTJlJL+jPp3DkSiQ0HiNeSYCad20CSljNvzKT/HJMwNmwm2i/H059Jzqipk5Nnb374mCgtCMBMmvJRMApGwSgYBfgAALowLacd8KHlAAAAAElFTkSuQmCC","orcid":"","institution":"Nanjing First Hospital","correspondingAuthor":true,"prefix":"","firstName":"Hongwei","middleName":"","lastName":"Shi","suffix":""}],"badges":[],"createdAt":"2024-03-09 12:32:55","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4055954/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4055954/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":53200547,"identity":"a494906b-a491-4a15-94f4-929fad9a5baa","added_by":"auto","created_at":"2024-03-21 19:27:52","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":290437,"visible":true,"origin":"","legend":"\u003cp\u003eEnrollment and randomization.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-4055954/v1/f6a2ad647d1dfa878f6f1e17.jpeg"},{"id":56116751,"identity":"4d551bf2-9a2d-4d43-a2bb-889e80485ae4","added_by":"auto","created_at":"2024-05-08 18:11:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":602853,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4055954/v1/72108f7c-42c5-425c-aba8-e9c0993612ae.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of high flow nasal cannula oxygen therapy versus nasal cannula in sedated transesophageal echocardiography in patients with mitral regurgitation: a prospective, randomized controlled clinical trial","fulltext":[{"header":"Background","content":"\u003cp\u003eIt is recognized that the most common valve heart disease is mitral regurgitation (MR). In China, the population of individuals with MR at a Grade III level or higher exceeds 10\u0026nbsp;million, necessitating therapeutic interventions[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Surgical valve repair or replacement is considered the standard method to treat MR and has been proven to relieve patients' symptoms and prolong their survival time. However, 50% of MR patients do not receive effective treatment because of high-risk factors such as low cardiac function, multiple comorbidities, and advanced age, which are not suitable for surgery [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. For patients deemed too old, too sick, or too risky for conventional open-heart surgery, the MitraClip is a viable therapy option [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Before undergoing TEER, echocardiography serves as a crucial technique for selecting patients in order to evaluate cardiac and valve function using the EVEREST criteria. [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo alleviate patients' apprehension, anxiety, and fear related to TEE and mitigate potential discomfort, adverse reactions, and complications arising from the esophageal ultrasonography probe's insertion into the esophagus through the pharynx, sedation is commonly administered during TEE procedures. The conventional nasal cannula employed for TEE under deep sedation is limited to delivering oxygen flow rates within the range of 2\u0026ndash;8 L/min [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Given that a substantial percentage of patients receiving TEE are elderly and exhibit compromised cardiopulmonary function with diminished oxygen reserves, they tend to be more susceptible to anesthetics and are at an increased risk of respiratory depression. This heightened vulnerability elevates the likelihood of perioperative hypoxemia [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Consequently, ensuring optimal oxygenation throughout the examination emerges as a critical challenge for anesthesiologists.\u003c/p\u003e \u003cp\u003eHigh-flow nasal cannula (HFNC) can provide warmed and moistened gas with a high flow rate and 100% concentration of oxygen [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. A growing number of patients receiving procedural sedation and analgesia rely on oxygen delivered via HFNC [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. To validate HFNC in various procedural sedations, randomized controlled trials have been carried out, including gastrointestinal endoscopy, bronchoscopy, endoscopic retrograde cholangiopancreatography, and atrial fibrillation catheter ablation [\u003cspan additionalcitationids=\"CR12 CR13\" citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Currently, there is no study comparing the use of HFNC and nasal cannula during sedated TEE. This research seeks to assess the efficacy of HFNC application in sedated TEE and provide relevant evidence for clinical practice.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design\u003c/h2\u003e \u003cp\u003eThis single-blind, prospective, randomized controlled trial received approval from the institutional review board of Nanjing First Hospital (KY20230116-08) and was pre-registered in the Chinese Clinical Trial Registry(ChiCTR2300068412, principal investigator: J. Gu, MD, PhD, date of registration: February 17, 2023), which can be reached at \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.chictr.org.cn/showproj.html?proj=190434\u003c/span\u003e\u003cspan address=\"https://www.chictr.org.cn/showproj.html?proj=190434\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. The research was carried out strictly in compliance with the Declaration of Helsinki and Good Clinical Practice guidelines and followed the consolidated Standards of Reporting Trials\u003c/p\u003e \u003cp\u003e (CONSORT) guidelines. Written informed consent was obtained from all patients.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003eIn this research, patients planned for a propofol-sedated TEE were recruited. The following were the inclusion criteria: (1)\u0026thinsp;\u0026ge;\u0026thinsp;18 years old; (2) BMI\u0026thinsp;\u0026lt;\u0026thinsp;30 kg/m2; (3) Planned mitra-clip surgery. The following were the exclusion criteria: (1) Coagulation disorders or tendency to nosebleeds; (2) Patients at high risk of reflux aspiration; (3) Acute arrhythmia accompanied by hemodynamic instability. hemodynamic instability; (4) History of intubation difficulties.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eRandomization and blinding\u003c/h2\u003e \u003cp\u003eEach patient was randomly allocated to either the HFNC group (Group H) or the nasal cannula oxygen group (Group C) at a 1:1 ratio, using computer randomization software (SPSS 21.0).\u003c/p\u003e \u003cp\u003eBlinded to the randomization grouping, an investigator registered and assigned participants. The randomization code was stored in a sealed opaque envelope, accessible solely to the researchers and opened prior to anesthesia induction. Postoperatively, patients were interviewed by team members who were not conscious of the randomization grouping, a team member registered and assigned participants.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eInterventions and anesthesia\u003c/h2\u003e \u003cp\u003eAfter the patients entered the room, electrocardiogram, respiration, blood pressure and peripheral oxygen saturation (SpO\u003csub\u003e2\u003c/sub\u003e) were monitored, and they were instructed to assume a supine position on their right side. Group C received 2 L/min of pure oxygen through nasal intubation, while HFNC group utilized HFNC (Fisher \u0026amp; Paykel, Panmure, New Zealand) for oxygen inhalation (30 L/min, FiO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;100%). In both groups, patients breathed calmly for 3 minutes, undergoing denitrification and oxygenation. Subsequently, the initial loading dose of propofol (0.5-1.0 mg/kg) was slowly injected intravenously. Once the patient's eyelash reflex disappeared, Group C continued to breathe pure oxygen through nasal cannula (2 L/min), while HFNC group adjusted the oxygen flow to 60 L/min. The esophageal probe insertion occurred when the Ramsay score was \u0026gt;\u0026thinsp;4 (indicating slow or no response to glabella tapping or loud auditory stimulation). Continuous monitoring and maintenance of Ramsay score\u0026thinsp;\u0026gt;\u0026thinsp;4 were ensured throughout the examination. During the procedure, the infusion rate of propofol was maintained at 25\u0026ndash;75 \u0026micro;g/kg/min and the total dosage was documented.\u003c/p\u003e \u003cp\u003eHypoxia in the peri-examination phase was managed through the following measures: (1) discontinue the medication and arouse the patient; (2) lift the jaw and increase the flow rate of oxygen; (3) withdraw the endoscope and initiate mask ventilation simultaneously; (4) endotracheal intubation. In cases of identified hypotension during evaluation, intravenous injection of ephedrine at a dose of 5\u0026ndash;10 mg was administered. If the heartbeat fell below 50 beats per minute, 0.25\u0026ndash;0.50 mg atropine was initiated.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eOutcomes and data collection\u003c/h2\u003e \u003cp\u003eThe main outcome was the incidence of hypoxia (75% \u0026le; SpO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026lt;\u0026thinsp;90% for \u0026lt;\u0026thinsp;60 s) during anesthesia [\u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe following were secondary outcomes: (1) hypoxia: subclinical respiratory depression (90% \u0026le; SpO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026lt;\u0026thinsp;95%); severe hypoxia (SpO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026lt;\u0026thinsp;75% for any duration or 75% \u0026le; SpO\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;\u0026lt;\u0026thinsp;90% for \u0026ge;\u0026thinsp;60 s); (2) Treatments for hypoxia ; (3) adverse events regarding HFNC within 30 min after TEE inspection (airway injury, pneumothorax, subcutaneous emphysema); (4) sedation-related adverse events (nausea/vomiting, reflux, sore throat, dyspnea, tract obstruction or asphyxia) [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]; (5) general information during TEE: mean arterial pressure (MAP), lowest MAP, lowest systolic blood pressure, vasoactive medication use, dosage of propofol and examination time; (6) doctors\u0026rsquo; and Patients\u0026rsquo; satisfaction with examination were also investigated by a 5- point Likert-type scale.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eSample size\u003c/h2\u003e \u003cp\u003eThe estimated difference in the incidence of hypoxia between the two groups was employed to calculate the sample size using PASS software (version 15.0; NCSS, LLC). According to our previous research, we observed that 30% of hypoxic incidents occurred during TEE. Anticipating an improvement in patient outcomes, we project that the implementation of HFNC is expected to reduce the rate to 15%. Based on a power of 80% and an α of 5%, a degree of freedom of 1 and factoring in a conservative attrition rate of 10%, our meticulous calculations indicated that 226 patients would be required.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eTo perform the statistical analysis, SPSS software (21.0, Inc., Chicago, IL, USA) was utilized. For every continuous variable, we conducted Levene's and Shapiro-Wilk tests. The statistics are shown as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations or median [25th and 75th percentiles] based on the test results. One-way ANOVA was carried out to evaluate the normally distributed measurement data (dosage of propofol) between groups, and pairwise comparisons were performed using the LSD method. The rank sum test was used to compare measurement data with skewed distributions (SpO\u003csub\u003e2\u003c/sub\u003e, duration, median 1 min after anesthetic induction, wake-up time) between groups. Dunn's method was applied for multiple comparisons. By applying a chi-square test or Fisher's exact test, we contrasted the frequency of hypoxia and sedation-related adverse events between the groups. The Boferroni method was used to adjust the \u003cem\u003eP\u003c/em\u003e value of the pairwise comparison. At \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05, statistical significance was established.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eAfter enrollment, 226 patients were randomly assigned to two groups from February 2023 to January 2024 (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In Group C, there were three patients who withdrew from the trial due to the incorrect collection of data. A comprehensive analysis was conducted on a total of 223 patients. There were no statistically significant variations found in the airway assessment indicators and baseline characteristics between the two groups (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). TEE time, propofol dosage, and hemodynamic index within the two groups were no different (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\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 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBaseline characteristics of the study participants\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup C(n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup H\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;113)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e72.3\u0026thinsp;\u0026plusmn;\u0026thinsp;11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e70.7\u0026thinsp;\u0026plusmn;\u0026thinsp;12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (male/female)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e81/29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e79/34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody mass index (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22.4\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.8\u0026thinsp;\u0026plusmn;\u0026thinsp;3.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eASA\u0026nbsp;grade (III/IV)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e102/8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e107/6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.55\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMallampati class (\u0026nbsp;I/II/III/IV)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e49/54/6/1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52/48/11/2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMouth opening (1/2/3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2/5/103\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3/3/107\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.69\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThyromental distance(I/II/III)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e98/12/0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e94/18/1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of hypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90(81.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e86(76.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.30\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of diabetes mellitus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40(36.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39(34.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.77\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLV ejection fraction (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34.2\u0026thinsp;\u0026plusmn;\u0026thinsp;8.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33.3\u0026thinsp;\u0026plusmn;\u0026thinsp;7.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePA pressure greater than 40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48 (15.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52 (17.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.72\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBaseline SpO\u003csub\u003e2\u003c/sub\u003e (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e97 (97, 99)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e98 (97, 98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations, a number of patients, number (%), or median (Q1, Q3). Abbreviations: ASA, American Society Anaesthesiologists. LV: left ventricle. Group C: nasal catheter oxygen group, Group H: HFNC group.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \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 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eData of TEE\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\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\u003eGroup\u0026nbsp;C\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup H\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;113)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDuration, min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDose of propofol, mg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e92.5\u0026thinsp;\u0026plusmn;\u0026thinsp;15.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95.3\u0026thinsp;\u0026plusmn;\u0026thinsp;12.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.14\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHypotension (MAP\u0026thinsp;\u0026lt;\u0026thinsp;60 mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27 (24.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26 (23.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.79\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLowest mean arterial pressure\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;100\u0026ndash;120 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5(4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5(4.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.96\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;80\u0026thinsp;\u0026lt;\u0026thinsp;100 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30(27.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33(29.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.75\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;60\u0026ndash;80 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48(43.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e49(43.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;60 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27 (24.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26 (23.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.79\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLowest systolic blood pressure\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;100\u0026ndash;120 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43(38.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47(41.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;80\u0026thinsp;\u0026lt;\u0026thinsp;100 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42(38.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e48(42.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026ge;60\u0026ndash;80 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24(21.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18(15.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u0026lt; 60 mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1(0.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.49\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVasoactive medication use\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27 (24.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25 (22.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD and median (Q1, Q3).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn comparison to nasal cannula oxygen, the utilization of HFNC demonstrated a significant reduction in the incidences of hypoxia and severe hypoxia, going from 26.3\u0026ndash;15.0% (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and 1.8\u0026ndash;0% (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), respectively (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eRespiratory-related adverse events and intervention\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" 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=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\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\u003eGroup\u0026nbsp;C\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup H\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;113)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTotal events\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e64(58.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37 (32.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSubclinical respiratory depression\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e33(30.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20(15.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ehypoxia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29(26.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17 (15.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSevere hypoxia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2(1.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.24\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eJaw lift\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37(33.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22(19.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMask ventilation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13(11.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMechanical ventilation for endotracheal intubation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1(0.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.49\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData are presented as a number of patients, number (%), or median (Q1, Q3).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn Group H, a significant reduction was observed in the frequency of hypoxia, the necessity for jaw lift maneuvers, and the reliance on mask ventilation for managing hypoxia-related adverse events (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), as shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. A patient in Group C experienced respiratory arrest. Immediate rescue measures, including tracheal intubation, were implemented. Subsequently, the individual was transferred to the cardiology intensive care unit for further treatment before safely discharge.\u003c/p\u003e \u003cp\u003eGroup H saw a lower occurrence of choking and paradoxical response compared with Group C (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The satisfaction scores of operators and anesthesiologists in group H were higher than those in group C (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). After patients were awakened, adverse events associated with HFNC breathing were noted 5 min and 30 min later. Pneumatic and airway injuries were not discovered in any of the patients.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSedation-related adverse events\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\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\u003eGroup\u0026nbsp;C\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup H\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;113)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParadoxical response\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(2.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReflux\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNausea/vomit\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAirway obstruction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0(0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChoking\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11(10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3(2.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData are presented as a number of patients, number (%), or median (Q1, Q3).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eLikert satisfaction scores of patients, operators and anesthesiologists\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\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\u003eGroup\u0026nbsp;C\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;110)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup H\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;113)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epatients\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4(3, 4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(3, 4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eoperators\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(3, 4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4(4, 5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eanesthesiologists\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3(3, 4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5(4, 5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eData are presented as a number of patients, median (Q1, Q3).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn our study, HFNC reduced the incidence of hypoxia during TEE from 26.3\u0026ndash;15.0% when compared to nasal cannula.\u003c/p\u003e \u003cp\u003eIn Group C, one patient suffered respiratory arrest and was sent to the cardiology intensive care unit for further treatment. However, there were no patients with severe hypoxia requiring tracheal intubation in Group H. In Group H, the low occurrence of hypoxia allowed the surgeon to proceed without waiting for the anesthesiologist to address it, resulting in a more uninterrupted operation. The satisfaction levels of both the surgeon and anesthesiologist were higher in Group H.\u003c/p\u003e \u003cp\u003eThis study found a higher incidence of hypoxia than Cooper B. Kersey's study, possibly because the patients in this study planned Mitraclip procedures [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. These individuals (low ejection fraction and pulmonary hypertension) might become more vulnerable to hypoxia and hemodynamic instability.\u003c/p\u003e \u003cp\u003eHFNC reduces dead space, elevates functional residual volume and positive end-expiratory pressure, while concurrently enhancing inspired oxygen levels [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. It has been shown in multiple studies that HFNC can improve patient oxygenation and comfort after gastrointestinal endoscopy, respiratory tract infections, and extubation. Nevertheless, few studies have been conducted on patients at high risk of cardiogenic hypoxia [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMR can adversely affect exercise tolerance and heighten susceptibility to hypoxia through various mechanisms. The backflow of blood into the left atrium during systole elevates pressure in the pulmonary circulation, inducing pulmonary congestion and edema. This scenario hampers gas exchange in the lungs, subsequently impairing the oxygenation of blood. Furthermore, the heightened workload on the heart can result in left ventricular dysfunction, exacerbating the reduction in exercise tolerance and increasing vulnerability to hypoxia. HFNC diminishes intrapulmonary shunting and imparts a specific level of positive end-expiratory pressure, causing an elevation in intrathoracic pressure. Consequently, this results in a partial collapse of the patient's inferior vena cava during inspiration, leading to a reduction in preload [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. In cases of cardiogenic pulmonary edema, HFNC proves beneficial in maintaining adequate oxygenation by augmenting respiratory load and facilitating efficient gas exchange [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The outcomes of this study align with those reported in previous research [\u003cspan additionalcitationids=\"CR23 CR24 CR25\" citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThis study has several limitations: (1) Divergent Definitions of Hypoxia: The study faced challenges due to variations in the definitions of hypoxia, leading to notable differences in the specified range and duration of SpO2 within these definitions. Consequently, the statistical data may not accurately reflect the specific distinctions in hypoxia incidence compared to previous studies; (2) Inadequate Monitoring of End-Expiratory Carbon Dioxide under HFNC: At higher oxygen flow rates with HFNC, there was a difficulty in accurately monitoring end-expiratory carbon dioxide levels. Due to limitations in hospital funding, blood carbon dioxide levels were not measured, potentially affecting the comprehensive assessment of respiratory parameters in these conditions.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study found that compared with nasal cannula, HFNC can lessen hypoxia during TEE examinations in MR patients.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eASA \u0026nbsp; American Society of Anesthesiologists\u003c/p\u003e\n\u003cp\u003eCONSORT \u0026nbsp;Consolidated Standards of Reporting Trials\u003c/p\u003e\n\u003cp\u003eHFNC \u0026nbsp;High flow nasal cannula oxygen therapy\u003c/p\u003e\n\u003cp\u003eLV \u0026nbsp;left ventricle\u003c/p\u003e\n\u003cp\u003eMAP \u0026nbsp;mean arterial pressure\u003c/p\u003e\n\u003cp\u003eMR \u0026nbsp;mitral regurgitation;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSD \u0026nbsp;standard deviation\u003c/p\u003e\n\u003cp\u003eSpO\u003csub\u003e2\u003c/sub\u003e\u0026nbsp; peripheral oxygen saturation\u003c/p\u003e\n\u003cp\u003eTEE \u0026nbsp;transesophageal echocardiography\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis single-blind, prospective, randomized controlled trial received approval from the institutional review board of Nanjing First Hospital (KY20230116-08) and was pre-registered in the Chinese Clinical Trial Registry (ChiCTR2300068412, principal investigator: J. Gu, MD, PhD, date of registration: 17/02/2023). The research was carried out strictly in compliance with the Declaration of Helsinki and Good Clinical Practice guidelines and\u0026nbsp;followed the CONSORT guidelines. Written informed consent was obtained from all patients.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and/or analyzed during the current study are not publicly available due to policy issues in the hospital but are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWanlin Li, Ziqi Qiu and Hongwei Shi designed the study. Yajie Xu and Zhaojing Fang recuited patients. Wenwen Zhang, Meirong Ling and Xiaoliang Wang conducted statistical analysis. Wanlin Li, Ziqi Qiu , Meirong Ling and Yong Zhang wrote the manuscript. The final version of the manuscript was read and approved by all authors.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLi J, Pan W, Yin Y, et al. Prevalence and correlates of mitral regurgitation in the current era: an echocardiography study of a Chinese patient population[J]. Acta Cardiol. 2016;71(1):55\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHu P, Liu XB, Liang J, et al. A hospital-based survey of patients with severe valvular heart disease in China[J]. Int J Cardiol. 2017;231:244\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHead SJ, van Leeuwen WJ, Van Mieghem NM, Kappetein AP. Surgical or transcatheter mitral valve intervention: complex disease requires complex decisions. EuroIntervention. 2014;9(10):1133\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKataoka A, Watanabe Y, OCEAN-SHD Family. MitraClip: a review of its current status and future perspectives. Cardiovasc Interv Ther. 2023;38(1):28\u0026ndash;38.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHahn RT, Saric M, Faletra FF, Garg R, Gillam LD, Horton K, et al. Recommended standards for the performance of transesoph-ageal echocardiographic screening for structural heart intervention: from the American Society of Echocardiography. J Am Soc Echocardiogr. 2022;35:1\u0026ndash;76.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHsu WC, Orr J, Lin SP, et al. Efficiency of oxygen delivery through different oxygen entrainment devices during sedation under low oxygen flow rate: a bench study. J Clin Monit Comput. 2018;32(3):519\u0026ndash;25.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eQadeer MA, Rocio Lopez A, Dumot JA, et al. Risk factors for hypoxemia during ambulatory gastrointestinal endoscopy in ASA I-II patients. Dig Dis Sci. 2009;54(5):1035\u0026ndash;40.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLodeserto FJ, Lettich TM, Rezaie SR. High-flow Nasal Cannula: Mechanisms of Action and Adult and Pediatric Indications. Cureus. 2018;10(11):e3639.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHern\u0026aacute;ndez G, Roca O, Colinas L. High-flow nasal cannula support therapy: new insights and improving performance. Crit Care. 2017;21(1):62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDrake MG, High-Flow. Nasal Cannula Oxygen in Adults: An Evidence-based Assessment. Ann Am Thorac Soc. 2018;15(2):145\u0026ndash;55.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHomberg MC, Bouman EA, Linz D, et al. High-flow nasal cannula versus standard low-flow nasal cannula during deep sedation in patients undergoing radiofrequency atrial fibrillation catheter ablation: a single-centre randomised controlled trial. Trials. 2022;23(1):378.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLonghini F, Pelaia C, Garofalo E, et al. High-flow nasal cannula oxygen therapy for outpatients undergoing flexible bronchoscopy: a randomised controlled trial. Thorax. 2022;77(1):58\u0026ndash;64.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee MJ, Cha B, Park JS, et al. Impact of High-Flow Nasal Cannula Oxygenation on the Prevention of Hypoxia During Endoscopic Retrograde Cholangiopancreatography in Elderly Patients: A Randomized Clinical Trial. Dig Dis Sci. 2022;67(8):4154\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLin Y, Zhang X, Li L, et al. High-flow nasal cannula oxygen therapy and hypoxia during gastroscopy with propofol sedation: a randomized multicenter clinical trial. Gastrointest Endosc. 2019;90(4):591\u0026ndash;601.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRiccio CA, Sarmiento S, Minhajuddin A, et al. High-flow versus standard nasal cannula in morbidly obese patients during colonoscopy: A prospective, randomized clinical trial. J Clin Anesth. 2019;54:19\u0026ndash;24.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eThiruvenkatarajan V, Dharmalingam A, Arenas G, et al. Effect of high-flow vs. low-flow nasal plus mouthguard oxygen therapy on hypoxaemia during sedation: a multicentre randomised controlled trial. Anaesthesia. 2022;77(1):46\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMason KP, Green SM, Piacevoli Q. Adverse event reporting tool to standardize the reporting and tracking of adverse events during procedural sedation: a consensus document from the World SIVA International Sedation Task Force. Br J Anaesth. 2012;108(1):13\u0026ndash;20.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYang ZY, Meng Q, Xu YH, et al. Supraglottic jet oxygenation and ventilation during colonoscopy under monitored anesthesia care: a controlled randomized clinical trial. Eur Rev Med Pharmacol Sci. 2016;20(6):1168\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKersey CB, Lele AV, Johnson MN, Pattock AM, Liu L, Huang GS, Kirkpatrick JN, Mazimba S, Jobarteh S, Kwon Y. The Quality and Safety of Sedation and Monitoring in Adults Undergoing Nonoperative Transesophageal Echocardiography. Am J Cardiol. 2023;194:40\u0026ndash;5.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParke R, McGuinness S, Eccleston M. Nasal high-flow therapy delivers low-level positive airway pressure. Br J Anaesth. 2009;103:886\u0026ndash;90.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHomberg MC, Bouman EA, Linz D, et al. High-flow nasal cannula versus standard low-flow nasal cannula during deep sedation in patients undergoing radiofrequency atrial fibrillation catheter ablation: a single-centre randomised controlled trial. Trials. 2022;23(1):378.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKo DR, Beom J, Lee HS, You JS, Chung HS, Chung SP. Benefits of high-flow nasal cannula therapy for acute pulmonary edema in patients with heart failure in the emergency department: a prospective multi-center randomized controlled trial. J Clin Med. 2020;21:1937.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMakdee O, Monsomboon A, Surabenjawong U, et al. High-Flow Nasal Cannula Versus Conventional Oxygen Therapy in Emergency Department Patients With Cardiogenic Pulmonary Edema: A Randomized Controlled Trial. Ann Emerg Med. 2017;70(4):465\u0026ndash;72.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKang MG, Kim K, Ju S, Park HW, Lee SJ, Koh JS, Hwang SJ, Hwang JY, Bae JS, Ahn JH, Jang JY, Park Y, Jeong YH, Kwak CH, Park JR. Clinical efficacy of high-flow oxygen therapy through nasal cannula in patients with acute heart failure. J Thorac Dis. 2019;11(2):410\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFraser JF, Spooner AJ, Dunster KR, Anstey CM, Corley A. Nasal high flow oxygen therapy in patients with COPD reduces respiratory rate and tissue carbon dioxide while increasing tidal and end-expiratory lung volumes: a randomised crossover trial. Thorax. 2016;71(8):759\u0026ndash;61.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchwabbauer N, Berg B, Blumenstock G, Haap M, Hetzel J, Riessen R. Nasal high-flow oxygen therapy in patients with hypoxic respiratory failure: effect on functional and subjective respiratory parameters compared to conventional oxygen therapy and non-invasive ventilation (NIV). BMC Anesthesiol. 2014;14:66.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"High flow nasal cannula, Transesophageal echocardiography, Sedation, Hypoxia","lastPublishedDoi":"10.21203/rs.3.rs-4055954/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4055954/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eHypoxia is common among mitral regurgitation patients and may be more susceptible to anesthetics. To evaluate the security and efficacy of high flow nasal cannula oxygen therapy (HFNC) and nasal cannula for sedated transesophageal echocardiography (TEE) in patients with mitral regurgitation.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003e226 patients scheduled to receive TEE under sedation were randomized into two groups: HFNC group (Group H) and nasal cannula group (Group C). The incidence of hypoxia during the TEE procedure was the main result. Secondary outcomes included hypoxia-related measures and interventions, ventilation and adverse events related to sedation.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eIn comparison to Group C, Group H exhibited a significant decrease in the incidences of hypoxia and severe hypoxia, dropping from 26.3\u0026ndash;15.0% (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and 1.8\u0026ndash;0% (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), respectively.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eCompared with nasal cannula, HFNC can reduce hypoxia during TEE procedure in patients with mitral regurgitation.\u003c/p\u003e\u003ch2\u003eTrial registration\u003c/h2\u003e \u003cp\u003eChiCTR2300068412, 17/02/2023.\u003c/p\u003e","manuscriptTitle":"Comparison of high flow nasal cannula oxygen therapy versus nasal cannula in sedated transesophageal echocardiography in patients with mitral regurgitation: a prospective, randomized controlled clinical trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-03-21 19:27:48","doi":"10.21203/rs.3.rs-4055954/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"335a93ce-e456-41aa-bbe9-2c5acf923f5d","owner":[],"postedDate":"March 21st, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-08T18:10:22+00:00","versionOfRecord":[],"versionCreatedAt":"2024-03-21 19:27:48","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4055954","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4055954","identity":"rs-4055954","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}