The Effectiveness of Ketamine on Non-invasive Ventilation Compliance in Acute Respiratory Failure

The Effectiveness of Ketamine on Non-invasive Ventilation Compliance in Acute Respiratory Failure | 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 The Effectiveness of Ketamine on Non-invasive Ventilation Compliance in Acute Respiratory Failure Çağatay Nuhoğlu, Görkem Alper Solakoğlu, Ferhat Arslan, Ömer Faruk Gülsoy, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3937336/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Oct, 2024 Read the published version in BMC Emergency Medicine → Version 1 posted 8 You are reading this latest preprint version Abstract Background In patients presenting to the emergency department (ED) with acute respiratory failure, non-invasive mechanical ventilation (NIMV) is applied when conventional oxygen support is not sufficient. Patients who are agitated often have very low NIMV compliance and a transition to invasive mechanical ventilation (IMV) is often required. To avoid IMV, a suitable sedative agent can be utilized. The aim of this research is to investigate the relationship between ketamine administration to patients who are non-compliant with NIMV due to agitation and the outcome of their intubation. Methods This retrospective study included patients with acute respiratory failure who were admitted to the ED from 2021 to 2022 and used Richmond Agitation Sedation Scale (RASS) for identify agitation level of patients. The relationship between ketamine administration in this patient group and NIMV compliance and intubation outcome was evaluated. Results A total of 81 patients, including 35 (43.2%) men and 46 (56.8%) women, were included in the study. Of these patients, 46 (56.8%) were intubated despite ketamine administration, while 35 (43.2%) were compliant with NIMV and were not intubated. When evaluating the RASS, which shows the agitation levels of the patients, the non-intubated group was found to be 2.17 ± 0.68, while the intubated group was 2.66 ± 0.73, and it was statistically significant that the NIMV intubated group was higher (p = 0.003). Conclusion This study showed that agitation can impair NIMV compliance in patients with acute respiratory failure. However, a significant proportion of this patient group can be avoided through IMV with proper sedative agents. Ketamine Psychomotor Agitation Noninvasive Ventilation Respiratory Insufficiency What is already known on the study topic? Patients who are agitated often have a very low NIMV compliance, and unfortunately, a transition to invasive mechanical ventilation is often required. To avoid invasive ventilation, a suitable sedative agent can be utilized. What is the conflict on the issue? Has it importance for readers? To improve the success of NIMV, we can use ketamine as a sedative agent to avoid invasive ventilation and extra medical costs. How is this study structured? This was a single-center, retrospective observational study that includes data from 81 patients. What does this study tell us? This study showed that agitation can impair NIMV compliance in patients with acute respiratory failure, but a significant proportion of this patient group can be avoided from invasive mechanical ventilation with proper sedative agents. Given its known effects, ketamine can be considered a suitable agent in this regard. INTRODUCTION Patients presenting with acute respiratory failure frequently belong to a critical patient group that requires urgent intervention and are commonly referred to the emergency department. The management of these patients involves hemodynamic monitoring, administration of necessary oxygen support, and development of a treatment plan directed at the underlying cause. In cases where conventional oxygen support is insufficient, non-invasive mechanical ventilation (NIMV) or invasive mechanical ventilation may be applied. Patients who are agitated often have a very low NIMV compliance, and unfortunately, a transition to invasive mechanical ventilation is often required. Invasive mechanical ventilation is a cost-effective approach compared to non-invasive mechanical ventilation as it increases the length of stay in the intensive care unit and increases the incidence of ventilator-associated pneumonia.[ 1 ] In patients who are within the indication for NIMV but are unable to comply due to agitation, sedative agents can be used to ensure patient compliance with the ventilator.[ 2 ] Considering that ketamine has both analgesic and anxiolytic effects, it may be superior to other sedative agents[ 3 ] it can be used as a sedative in patients presenting with acute respiratory failure due to its lack of respiratory depression and its lack of negative effect on hemodynamics. The Richmond Agitation-Sedation Scale (RASS) can be used to measure the agitation levels of patients presenting to the emergency department.[ 4 ] In this study, the relationship between the application of 0.5 mg/kg ketamine in patients with acute respiratory failure who presented to the emergency department and who had an agitation level of + 2 or higher according to the RASS score and ended up with intubation was investigated. The scoring system described in the introduction is useful, simple, and can be applied quickly for measuring both the level of agitation and sedation. It is particularly advantageous in acute situations such as acute respiratory failure as it can be quickly and repeatedly applied. METHODS This study is a retrospective study conducted on patients with acute respiratory failure who were admitted to tour clinic. 81 patients were included in the study who were given ketamine due to the reason that they could not tolerate NIMV due to agitation. The study was carried out with the approval of the Clinical Research Ethics Committee of XXX Hospital with Ethical Committee Approval No. 2022/0489 and 17.08.2022. The study analyzed the gender, age, chronic diseases, vital signs, saturation and respiratory rates, relationship between intubation and ketamine administration, and adverse effects caused by ketamine administration between 01.06.2021 to 01.08.2022. The study population was determined based on the following criteria. Patients who met the criteria below were included in the study: 18 years of age or older Patients with hypoxia despite standard oxygen support (Sao2 25 tachypneic Patients with hypercapnia (Paco2>45) Use of assistive respiratory muscles / abdominal breathing Patients with RASS +2 or higher Patients who received 0.5 mg/kg of ketamine as the first and second dose Patients who meet at least one of the following criteria were excluded from the study: Patients with cardiopulmonary arrest Patients with NIMV unsuitability due to craniofacial trauma Patients with mask incompatibility due to anatomical abnormalities Patients in whom complications are expected or mortality may increase in the case of a delay in invasive mechanical ventilation. Patients who cannot undergo NIMV due to clouding of consciousness. Active upper gastrointestinal bleeding Patients who recently underwent head and neck or oesophageal surgery The patients forming the study universe were managed by emergency medicine specialists and residents in the resuscitation section of the emergency department and their findings and outcomes were recorded by them. The data were collected from the our Hospital data management system and patient files. Statistical analyses In this study, statistical analyses were performed using the NCSS (Number Cruncher Statistical System) 2007 Statistical Software (Utah, USA) package. Descriptive statistical methods (mean, standard deviation) were used to evaluate the data, and the Shapiro – Wilk normality test was used to examine the distribution of variables. For variables showing normal distribution, independent t-test was used for comparing two groups, and chi-square and Fisher's exact test were used for comparing categorical data. Logistic regression analysis was performed to determine the factors affecting the presence of NIMV intubation. The results were evaluated at a significance level of p<0.05. RESULTS In this study, 81 patients, 35 (43.2%) male and 46 (56.8%) female, who could not tolerate NIMV due to agitation caused by acute respiratory failure were included. The group in which NIMV was unsuccessful and resulted in intubation was defined as NIMV Intubation (+), while the group in which the patient was cooperative, and intubation was not necessary was defined as NIMV Intubation (-). (Table 1) The mean age for NIMV Intubation (-) was 75.93 ± 11.39 and for NIMV Intubation (+) was 78.51 ± 12.49. Out of the males, 17 (43.57%) resulted in intubation, while 18 (51.43%) of the females resulted in intubation. There was no statistically significant difference in the mean age and gender distribution between the NIMV Intubation (-) and NIMV Intubation (+) groups (p = 0.336, p = 0.395). Out of the patients, 46 (56.8%) required intubation despite ketamine, while 35 (43.2%) were able to tolerate NIMV without intubation. (Table 1) When the patients' presentations were evaluated, the distribution was as follows: asthma attack 2 (2.4%), decompensated heart failure 26 (32%), hypertensive pulmonary edema 12 (14.8%), interstitial lung disease 1 (1.2%), COPD attack 28 (34.5%), malignant effusion 1 (1.2%), pneumonia 11 (13.5%). There was no statistically significant relationship between the clinical background of the patients and intubation outcome (p > 0.05). (Table 1) When the patients' chronic diseases were evaluated, there were 59 (72.8%) with hypertension, 26 (32%) with diabetes mellitus, 22 (27.1%) with chronic heart failure, 24 (29.6%) with coronary artery disease, 6 (7.4%) with chronic kidney failure, and 41 (50.6%) with COPD or asthma. There were statistically significant differences among the patients with hypertension and CHF. The presence of hypertension was statistically significantly lower in the NIMV Intubation (+) group compared to the NIMV Intubation (-) group (p = 0.023), and the presence of CHF in the NIMV Intubation (+) group was also statistically significantly lower compared to the NIMV Intubation (-) group (p = 0.023). No differences were found in other chronic diseases. (Table 1) The oxygen saturation levels under masks of patients in the group that resulted in intubation were found to be 78.4±10.97, while in the group that did not result in intubation, it was 88.46±5.55, and it was found to be statistically significant that patients with more desaturation were intubated (p=0.0001). However, no statistically significant relationship was found between the number of breaths the patients took and the outcome of intubation (p=0.754). (Table 1) When evaluating the RASS scale, which shows the level of agitation of patients, the non-intubated group was found to be 2.17±0.68, and the intubated group was 2.66±0.73, and it was found to be statistically significant that NIMV intubation (+) group was higher (p=0.003). (Table 1) The second dose of ketamine was found to be statistically significantly higher in the NIMV intubation (+) group compared to the NIMV intubation (-) group after the first dose of ketamine was found to be insufficient (p=0.0001). All patients who required a second dose of ketamine were intubated, while only one patient was intubated without a second dose of ketamine. No second dose of ketamine was needed for all patients who did not result in intubation. The adverse effects of ketamine after administration were as follows: Three or more consecutive ventricular ectopic beats in ECG Hypersalivation A decrease in systolic blood pressure of more than 20 mm Hg An increase in heart rate of 20 or more Of the 81 patients included in the study, the adverse effects of ketamine were detected in 8 (9.8%). The effect of hypersalivation was only seen in 1 (1.2%) patient. No statistically significant difference was observed in the distribution of the presence of ketamine adverse effects between the NIMV intubation (-) and NIMV intubation (+) groups (p=0.178). (Table 2) A logistic regression analysis was conducted to determine the factors affecting NIMV intubation using the HT, KKY, Mask-under SpO2, and RASS Agitation Score variables. The HT (p=0.627) and KKY (p=0.943) variables were found to be insignificant, while the decrease in Mask-under SpO2 (p=0.0001) and the increase in RASS Agitation Score (p=0.033) were identified as the factors affecting NIMV intubation with NIMV application. (Table 3) DISCUSSION Non-invasive ventilation (NIMV) has been shown to be effective in avoiding intubation and improving survival in patients with acute hypoxemic respiratory failure compared to conventional oxygen therapy.[ 5 ] However, the patient's failure to adapt to mechanical ventilation or the occurrence of agitation due to respiratory distress can significantly reduce the success of NIMV. There are some case reports in the literature indicating that ketamine can be applied to patients who cannot tolerate NIMV due to agitation and success can be achieved .[ 6 , 7 ] In our study, similar success rates were observed in patients with exacerbation of COPD, decompensated heart failure, hypertensive pulmonary edema, and pneumonia. The reason for the preference of ketamine over other sedatives may be explained by its anxiolytic effect and the absence of negative effects on respiration and hemodynamics. The clinical cases mentioned in the case reports in the literature are asthma attack and acute cardiogenic pulmonary edema [ 3 ]. At present, ketamine is used at the Emergency Medicine Clinic of for procedural sedation, deep sedation for intubation preparation, and sedation of agitated patients who cannot tolerate non-invasive mechanical ventilation. In the meta-analysis performed, serious cardiopulmonary adverse effects were found to be quite rare among the adverse effects of ketamine, and in our study, no serious adverse effects were observed. The frequency of adverse effects was found to be 9.8% and was found to be in line with the literature.[ 8 ] However, higher doses may lead to the occurrence of dissociative effects, which are not suitable for ventilator compatibility, and invasive ventilation may be required. Hypersalivation effect, which can disrupt ventilation compatibility, was observed in only one patient, and did not result in intubation. The effect, which was only detected in 1.2%, was not considered appropriate to avoid ketamine in NIMV applications. The dissociative effect of ketamine starts at doses above 1-1.5 mg/kg. The first and second doses of 0.5 mg/kg of ketamine were administered to patients included in the study, so no dissociative effect was observed. Other side effects detected included a systolic blood pressure increase of 20 mm Hg or more, 3 or more consecutive ventricular ectopic beats on the ECG, and a heart peak rate increase of 20 or more, which did not affect the patient's outcome with intubation. The side effects caused by ketamine at low doses are not sufficient to avoid NIMV.[ 9 ] NIMV cannot be initiated unless the required comfort and ventilation compliance are achieved, and if adequate oxygenation cannot be achieved, direct invasive ventilation is required. The Richmond Agitation-Sedation Scale is used to measure the levels of agitation and sedation in the patient. In critically ill patients with acute respiratory failure, the scoring used must be rapid, reliable, and repeatable. In a comparative study with the Ramsay Sedation Scale, the Richmond Agitation-Sedation Scale (RASS) was found to be more reliable.[ 10 ] According to this scoring system, patients with an agitation level of + 2 or higher were included in the study and patients with high levels of agitation in this scoring resulted in more intubation. Most of the patients who resulted in intubation had to be given a second dose of ketamine. This is likely since the agitation levels were higher. Moreover, considering that the need for a second dose of ketamine arose from agitation levels or inability to achieve sufficient compliance with NIMV using the first sedation dose, it may be more appropriate to directly proceed to invasive ventilation instead of waiting for the second ketamine dose for these patients. A study conducted on high-flow nasal oxygen showed that the failure of HFNO increased mortality by causing a delay in intubation, which is why continuing NIMV insufficiency in a patient by waiting for a second dose of ketamine and not providing adequate oxygen support for a longer period may negatively impact the outcome.[ 11 ] Our study included 81 patients who were unable to tolerate NIMV due to agitation and would have required invasive mechanical ventilation if ketamine was not administered. In 43.2% of this patient group, intubation was avoided. A widespread epidemiological study in the United States has shown that mechanical ventilation has a relationship with mortality and is a significant economic burden on the health system.[ 12 ] In the study group of hospitalized patients, 2.7% required mechanical ventilation and the total cost was estimated to be 2.7 billion US dollars. It is recommended to implement cost-saving measures. In a study on complications related to mechanical ventilation, 9.3% of 597 patients were found to have ventilator-associated pneumonia.[ 13 ] The expected mortality rate for ventilator-associated pneumonia is in the 10% range and is expected to be higher in critically ill patients. Although the patient group unable to tolerate NIMV due to agitation is small, using ketamine to prevent the transition to invasive ventilation may be significant in terms of both cost and patient survival.[ 14 ] Between 40–60% FiO2 can be delivered with simple mask oxygenation. Despite this oxygen support, lower So2 values were found in the group of intubated patients. In this context, sedating critically ill patients with lower oxygen saturation using ketamine has made it more difficult to avoid intubation. When the predictors of intubation were evaluated in a study, it was shown that having a high respiratory rate under conventional oxygen support increases the likelihood of ending with intubation.[ 15 ] In our study, the administration of ketamine did not result in a statistically significant difference in the incidence of intubation outcomes as judged by the respiratory rate. This could be attributed to the fact that all the patients included in the study were monitored and the increase in respiratory rate in the group of patients with more than 25 breaths per minute may not be related to the outcome of intubation. The study did not find a statistically significant difference in the intubation outcomes of patients admitted to the emergency department based on their presenting clinical features. A meta-analysis study evaluated the relationship between non-invasive mechanical ventilation (NIMV) and mortality in acute respiratory failure, including 25 randomized controlled trials with a total of 3804 patients.[ 16 ] Studies have shown that there is a significant decrease in mortality compared to standard oxygen support, regardless of the presenting clinical severity. Offering non-invasive mechanical ventilation (NIMV) opportunity to patients prior to intubation can be positive in terms of patient survival, regardless of the referral clinics. The literature also demonstrates the positive effect of NIMV implementation on chronic respiratory failure in a significant portion of patients, which is mainly made up of exacerbation of chronic obstructive pulmonary disease (COPD) patients in both groups.[ 17 ] When evaluating chronic illnesses, it has been shown through logistic regression analysis that the presence of hypertension and congestive heart failure does not significantly affect the rate of intubation outcome. No significant relationship has been found between other chronic illnesses and intubation outcome. This suggests that in patients with acute respiratory failure, the administration of ketamine may be beneficial in avoiding intubation, regardless of the patient's known chronic illnesses. When compared to other sedative agents used during non-invasive mechanical ventilation (NIMV), ketamine has been found to be more effective than midazolam, propofol, and the opioid group, but less effective than dextromethorphan.[ 18 ] LIMITATIONS It is not sufficient to definitively state that ketamine is a suitable sedative agent for NIMVM tolerance. Its efficacy can be better demonstrated through larger-scale studies in the future. The exclusion of patients who used other sedative agents for NIMV agitation creates a limitation in the evaluation of ketamine compared to other agents. The relationship between ketamine administration in NIMV non-compliance and intubation has been discussed with articles available, due to the lack of sufficient prospective randomized studies investigating the issue. CONCLUSION In patients with acute respiratory failure, agitation can disrupt NIMV compliance, but a proper sedative agent can help ensure NIMV compliance in a significant proportion of this patient group, avoiding the need for invasive mechanical ventilation. Considering the known effects of ketamine in this regard, it may be considered as a suitable agent. Given that ketamine applications at doses greater than 0.5 mg/kg do not have an impact on ending intubation, delaying invasive mechanical ventilation with a second dose of ketamine may not be appropriate. To reduce the cost of invasive mechanical ventilation and its adverse effects on patient outcome, ketamine for sedation may be a suitable option for strategies aimed at mitigating these outcomes. Abbreviations ED: Emergency Department NIMV: Non-invasive mechanical ventilation IV: Invasive ventilation IMV: Invasive mechanical ventilation RASS: Richmond Agitation Sedation Scale Declarations Ethics approval and consent to participate Consent to Participate – A detailed written patient consent statement was obtained. Ethical Approval – İstanbul Medeniyet University Göztepe Prof. Dr. Süleyman City Hospital Ethical Comitee of Clinical Reseraches Date: 17.08.2022 No: 2022/0489 Competing interests The authors declare that they have no competing interests Funding There is no sponsor and no funding to declare. Author Contributions CN: Conceptualization (lead); writing – original draft (lead); formal analysis (lead); writing – review and editing (equal). GAS: Software (lead); writing – review, and editing (equal). FA: Methodology (lead); writing – review, and editing (equal). ÖFG: Methodology (lead); writing – review, and editing (equal). KOD: Methodology (lead); writing – review, and editing (equal). References Yeow M-E, Santanilla JI (2008) Noninvasive positive pressure ventilation in the emergency department. Emerg Med Clin North Am 26:835–847, x. https://doi.org/10.1016/j.emc.2008.04.005 Wysocki M, Antonelli M (2001) Noninvasive mechanical ventilation in acute hypoxaemic respiratory failure. European Respiratory Journal 18:209–220 Green SM, Roback MG, Kennedy RM, Krauss B (2011) Clinical practice guideline for emergency department ketamine dissociative sedation: 2011 update. Ann Emerg Med 57:449–461. https://doi.org/10.1016/j.annemergmed.2010.11.030 Ely EW, Truman B, Shintani A, et al (2003) Monitoring Sedation Status Over Time in ICU Patients: Reliability and Validity of the Richmond Agitation-Sedation Scale (RASS). JAMA 289:2983. https://doi.org/10.1001/jama.289.22.2983 Hillberg RE, Johnson DC (1997) Noninvasive ventilation. N Engl J Med 337:1746–1752. https://doi.org/10.1056/NEJM199712113372407 Kiureghian E, Kowalski JM (2015) Intravenous ketamine to facilitate noninvasive ventilation in a patient with a severe asthma exacerbation. The American Journal of Emergency Medicine 33:1720.e1-1720.e2. https://doi.org/10.1016/j.ajem.2015.03.066 Verma A, Snehy A, Vishen A, et al (2019) Ketamine Use allows Noninvasive Ventilation in Distressed Patients with Acute Decompensated Heart Failure. Indian J Crit Care Med 23:191–192. https://doi.org/10.5005/jp-journals-10071-23153 Strayer RJ, Nelson LS (2008) Adverse events associated with ketamine for procedural sedation in adults. Am J Emerg Med 26:985–1028. https://doi.org/10.1016/j.ajem.2007.12.005 Ozyilmaz E, Ugurlu AO, Nava S (2014) Timing of noninvasive ventilation failure: causes, risk factors, and potential remedies. BMC Pulmonary Medicine 14:19. https://doi.org/10.1186/1471-2466-14-19 Rasheed AM, Amirah MF, Abdallah M, et al (2019) Ramsay Sedation Scale and Richmond Agitation Sedation Scale: A Cross-sectional Study. Dimensions of Critical Care Nursing 38:90–95. https://doi.org/10.1097/DCC.0000000000000346 Perkins GD, Ji C, Connolly BA, et al (2022) Effect of Noninvasive Respiratory Strategies on Intubation or Mortality Among Patients With Acute Hypoxemic Respiratory Failure and COVID-19: The RECOVERY-RS Randomized Clinical Trial. JAMA 327:546–558. https://doi.org/10.1001/jama.2022.0028 Wunsch H, Linde-Zwirble WT, Angus DC, et al (2010) The epidemiology of mechanical ventilation use in the United States*. Critical Care Medicine 38:1947–1953. https://doi.org/10.1097/CCM.0b013e3181ef4460 Klompas M, Khan Y, Kleinman K, et al (2011) Multicenter Evaluation of a Novel Surveillance Paradigm for Complications of Mechanical Ventilation. PLOS ONE 6:e18062. https://doi.org/10.1371/journal.pone.0018062 Papazian L, Klompas M, Luyt C-E (2020) Ventilator-associated pneumonia in adults: a narrative review. Intensive Care Med 46:888–906. https://doi.org/10.1007/s00134-020-05980-0 Frat J-P, Ragot S, Coudroy R, et al (2018) Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy*. Critical Care Medicine 46:208–215. https://doi.org/10.1097/CCM.0000000000002818 Ferreyro BL, Angriman F, Munshi L, et al (2020) Association of Noninvasive Oxygenation Strategies With All-Cause Mortality in Adults With Acute Hypoxemic Respiratory Failure: A Systematic Review and Meta-analysis. JAMA 324:57–67. https://doi.org/10.1001/jama.2020.9524 Kolodziej MA, Jensen L, Rowe B, Sin D (2007) Systematic review of noninvasive positive pressure ventilation in severe stable COPD. European Respiratory Journal 30:293–306. https://doi.org/10.1183/09031936.00145106 Longrois D, Conti G, Mantz J, et al (2014) Sedation in non-invasive ventilation: do we know what to do (and why)? Multidiscip Respir Med 9:56. https://doi.org/10.1186/2049-6958-9-56 Tables Table 1: Demographic structures of patients, chronic diseases, other findings and their relationship with intubation No intubation n :46 (56.8%) Intubation n:35 (43.2%) p Age 75.93±11.39 78.51±12.49 0.336* Gender Male 18 39.13% 17 48.57% 0.395+ Female 28 60.87% 18 51.43% Present clinical situation Asthma Attack 2 4.35% 0 0.00% 0.503ǂ Decompansated kardiac failure 19 41,30% 7 20.00% 0.073+ Hypertensive pulmonary edema 4 8.70% 8 22.86% 0.144+ Interstitial lung disease 0 0.00% 1 2.86% 0.890ǂ COPD Attack 15 32.61% 13 37.14% 0.849 Malignant effusion one 2.17% 0 0.00% 0.890ǂ Pneumonia 5 10.87% 6 17.14% 0.625+ HT 38 82.61% 21 60.00% 0.023+ DM 15 32.61% 11 31.43% 0.910+ CHF 17 36.96% 5 14.29% 0.023+ CAD 15 32.61% 9 25.71% 0.501+ KRG 4 8.70% 2 5.71% 0.612+ COPD+Asthma 24 52.17% 17 48.57% 0.748+ CVO 5 10.87% 7 20.00% 0.252+ CKD 2 4.35% 3 8.57% 0.434+ Alzheimer's 3 6.52% one 2.86% 0.451ǂ Malignity 3 6.52% 2 5.71% 0.881+ Under The Mask Spo2 88.46±5.55 78.4±10.97 0.0001* Respiration Rate 38.28±4.55 38.63±5.35 0.754* RASS Agitation Score 2.17±0.68 2.66±0.73 0.003* a second administration of ketamine necessary? No 46 100.00% one 2.86% 0.0001 ǂ Yes 0 0.00% 34 97.14% Adverse effect of ketamine No 39 84.78% 33 94.29% 0.178+ Yes 7 15.22% 2 5.71% *Independent t test + Chi-square test ǂFisher's Reality Test Table 2: Relation of Adverse Effect of Ketamine with Intubation Adverse effect of ketamine NIMV Intubation (-) n:46 NIMV Intubation (+) n:35 3 consecutive VES on ECG 2 33.33% 0 0.00% hypersalivation one 16.67% 0 0.00% Blood Pressure 20 mmHG drop 0 0.00% 2 100.00% HR 20 increase 3 50.00% 0 0.00% Table 3: Logistic Regression Analysis OR 95% OR p HT 1.4 0.36-5.43 0.627 CHF 1.05 0.27-4.15 0.943 SpO2 under the mask 0.86* 0.79-0.94* 0.0001* RASS Agitation Score 2.45 1.08-5.55 0.033* Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 11 Oct, 2024 Read the published version in BMC Emergency Medicine → Version 1 posted Editorial decision: Revision requested 03 Apr, 2024 Reviews received at journal 27 Mar, 2024 Reviewers agreed at journal 19 Mar, 2024 Reviewers invited by journal 18 Mar, 2024 Editor invited by journal 16 Feb, 2024 Editor assigned by journal 16 Feb, 2024 Submission checks completed at journal 16 Feb, 2024 First submitted to journal 07 Feb, 2024 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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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-3937336","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":271590396,"identity":"e6413033-9d48-470c-9898-8e4f5683f0ce","order_by":0,"name":"Çağatay Nuhoğlu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBUlEQVRIiWNgGAWjYFACHiAugPNsgJix8QBhLQZgFmMDA0MamCZJy2EwC68Wc4ncgw+/GByW5+9f/PzBz7bzdmvbDwNtqbGJxqXFckZesrGMwWHDGTeeGTb2tt1O3nYmEajlWFpuAw4tBjdyzKQlDA4nMNw4YNjAC9RidgCohbHhMGEt8jeOf2z823Yu2ez8Q8JaJD8AtRic7zFs5m07YGd2g5AtZ94YGzMYpBtuvMFTOFvmXHKC2Q2gLQn4/HI8x/Dhjwprebnzxzd8fFNmZ292Pv3hgw81Nji1gAAzKGoYJBKAMcPGkAhWmYBHOQgw/gCR/AeAxB8GewKKR8EoGAWjYAQCALusatFHo+Y2AAAAAElFTkSuQmCC","orcid":"","institution":"Şişli Etfal Eğitim ve Araştırma Hastanesi","correspondingAuthor":true,"prefix":"","firstName":"Çağatay","middleName":"","lastName":"Nuhoğlu","suffix":""},{"id":271590397,"identity":"95c02d03-9d30-4a5e-a496-6db7f6a64369","order_by":1,"name":"Görkem Alper Solakoğlu","email":"","orcid":"","institution":"Istanbul Medeniyet University","correspondingAuthor":false,"prefix":"","firstName":"Görkem","middleName":"Alper","lastName":"Solakoğlu","suffix":""},{"id":271590398,"identity":"04b40264-8d18-44bb-be9f-4278305142ac","order_by":2,"name":"Ferhat Arslan","email":"","orcid":"","institution":"Dr. Ersin Arslan Eğitim ve Araştırma Hastanesi","correspondingAuthor":false,"prefix":"","firstName":"Ferhat","middleName":"","lastName":"Arslan","suffix":""},{"id":271590399,"identity":"c1c2aa9b-5ca5-496e-8d3a-6d73816f9fce","order_by":3,"name":"Ömer Faruk Gülsoy","email":"","orcid":"","institution":"Siirt Eğitim ve Araştırma Hastanesi","correspondingAuthor":false,"prefix":"","firstName":"Ömer","middleName":"Faruk","lastName":"Gülsoy","suffix":""},{"id":271590400,"identity":"a5425c1f-3601-413a-8a7b-31b896c11bbc","order_by":4,"name":"Kamil Oğuzhan Döker","email":"","orcid":"","institution":"Emergency Departmant of Doğanşehir Hospital","correspondingAuthor":false,"prefix":"","firstName":"Kamil","middleName":"Oğuzhan","lastName":"Döker","suffix":""}],"badges":[],"createdAt":"2024-02-07 15:45:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3937336/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3937336/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12873-024-01100-z","type":"published","date":"2024-10-11T15:57:34+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":66597151,"identity":"6f315bf2-74ac-4512-9f3c-f36708dd2bab","added_by":"auto","created_at":"2024-10-14 16:07:45","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":699841,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3937336/v1/24aa7bf4-a9bd-4a7f-bd17-2bdc86ced0c9.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eThe Effectiveness of Ketamine on Non-invasive Ventilation Compliance in Acute Respiratory Failure\u003c/p\u003e","fulltext":[{"header":"What is already known on the study topic?","content":"\u003cul\u003e\n \u003cli\u003ePatients who are agitated often have a very low NIMV compliance, and unfortunately, a transition to invasive mechanical ventilation is often required. To avoid invasive ventilation, a suitable sedative agent can be utilized.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the conflict on the issue? Has it importance for readers?\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eTo improve the success of NIMV, we can use ketamine as a sedative agent to avoid invasive ventilation and extra medical costs.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eHow is this study structured?\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eThis was a single-center, retrospective observational study that includes data from 81 patients.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;What does this study tell us?\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eThis study showed that agitation can impair NIMV compliance in patients with acute respiratory failure, but a significant proportion of this patient group can be avoided from invasive mechanical ventilation with proper sedative agents.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eGiven its known effects, ketamine can be considered a suitable agent in this regard.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"INTRODUCTION","content":"\u003cp\u003ePatients presenting with acute respiratory failure frequently belong to a critical patient group that requires urgent intervention and are commonly referred to the emergency department. The management of these patients involves hemodynamic monitoring, administration of necessary oxygen support, and development of a treatment plan directed at the underlying cause. In cases where conventional oxygen support is insufficient, non-invasive mechanical ventilation (NIMV) or invasive mechanical ventilation may be applied. Patients who are agitated often have a very low NIMV compliance, and unfortunately, a transition to invasive mechanical ventilation is often required. Invasive mechanical ventilation is a cost-effective approach compared to non-invasive mechanical ventilation as it increases the length of stay in the intensive care unit and increases the incidence of ventilator-associated pneumonia.[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eIn patients who are within the indication for NIMV but are unable to comply due to agitation, sedative agents can be used to ensure patient compliance with the ventilator.[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] Considering that ketamine has both analgesic and anxiolytic effects, it may be superior to other sedative agents[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] it can be used as a sedative in patients presenting with acute respiratory failure due to its lack of respiratory depression and its lack of negative effect on hemodynamics. The Richmond Agitation-Sedation Scale (RASS) can be used to measure the agitation levels of patients presenting to the emergency department.[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eIn this study, the relationship between the application of 0.5 mg/kg ketamine in patients with acute respiratory failure who presented to the emergency department and who had an agitation level of +\u0026thinsp;2 or higher according to the RASS score and ended up with intubation was investigated. The scoring system described in the introduction is useful, simple, and can be applied quickly for measuring both the level of agitation and sedation. It is particularly advantageous in acute situations such as acute respiratory failure as it can be quickly and repeatedly applied.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003eThis study is a retrospective study conducted on patients with acute respiratory failure who were admitted to tour clinic. 81 patients were included in the study who were given ketamine due to the reason that they could not tolerate NIMV due to agitation. The study was carried out with the approval of the Clinical Research Ethics Committee of XXX Hospital with Ethical Committee Approval No.\u0026nbsp;2022/0489 and 17.08.2022. The study analyzed the gender, age, chronic diseases, vital signs, saturation and respiratory rates, relationship between intubation and ketamine administration, and adverse effects caused by ketamine administration between 01.06.2021 to 01.08.2022.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe study population was determined based on the following criteria. Patients who met the criteria below were included in the study:\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003e18 years of age or older\u003c/li\u003e\n \u003cli\u003ePatients with hypoxia despite standard oxygen support (Sao2 \u0026lt;92)\u003c/li\u003e\n \u003cli\u003ePatients with a respiratory rate of \u0026gt; 25 tachypneic\u003c/li\u003e\n \u003cli\u003ePatients with hypercapnia (Paco2\u0026gt;45)\u003c/li\u003e\n \u003cli\u003eUse of assistive respiratory muscles / abdominal breathing\u003c/li\u003e\n \u003cli\u003ePatients with RASS +2 or higher\u003c/li\u003e\n \u003cli\u003ePatients who received 0.5 mg/kg of ketamine as the first and second dose\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003ePatients who meet at least one of the following criteria were excluded from the study:\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003ePatients with cardiopulmonary arrest\u003c/li\u003e\n \u003cli\u003ePatients with NIMV unsuitability due to craniofacial trauma\u003c/li\u003e\n \u003cli\u003ePatients with mask incompatibility due to anatomical abnormalities\u003c/li\u003e\n \u003cli\u003ePatients in whom complications are expected or mortality may increase in the case of a delay in invasive mechanical ventilation.\u003c/li\u003e\n \u003cli\u003ePatients who cannot undergo NIMV due to clouding of consciousness.\u003c/li\u003e\n \u003cli\u003eActive upper gastrointestinal bleeding\u003c/li\u003e\n \u003cli\u003ePatients who recently underwent head and neck or oesophageal surgery\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eThe patients forming the study universe were managed by emergency medicine specialists and residents in the resuscitation section of the emergency department and their findings and outcomes were recorded by them. The data were collected from the our Hospital data management system and patient files.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analyses\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn this study, statistical analyses were performed using the NCSS (Number Cruncher Statistical System) 2007 Statistical Software (Utah, USA) package. Descriptive statistical methods (mean, standard deviation) were used to evaluate the data, and the Shapiro – Wilk normality test was used to examine the distribution of variables. For variables showing normal distribution, independent t-test was used for comparing two groups, and chi-square and Fisher's exact test were used for comparing categorical data. Logistic regression analysis was performed to determine the factors affecting the presence of NIMV intubation. The results were evaluated at a significance level of p\u0026lt;0.05.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eIn this study, 81 patients, 35 (43.2%) male and 46 (56.8%) female, who could not tolerate NIMV due to agitation caused by acute respiratory failure were included. The group in which NIMV was unsuccessful and resulted in intubation was defined as NIMV Intubation (+), while the group in which the patient was cooperative, and intubation was not necessary was defined as NIMV Intubation (-). (Table 1)\u003c/p\u003e\n\u003cp\u003eThe mean age for NIMV Intubation (-) was 75.93 ± 11.39 and for NIMV Intubation (+) was 78.51 ± 12.49. Out of the males, 17 (43.57%) resulted in intubation, while 18 (51.43%) of the females resulted in intubation. There was no statistically significant difference in the mean age and gender distribution between the NIMV Intubation (-) and NIMV Intubation (+) groups (p = 0.336, p = 0.395). Out of the patients, 46 (56.8%) required intubation despite ketamine, while 35 (43.2%) were able to tolerate NIMV without intubation. (Table 1)\u003c/p\u003e\n\u003cp\u003eWhen the patients' presentations were evaluated, the distribution was as follows: asthma attack 2 (2.4%), decompensated heart failure 26 (32%), hypertensive pulmonary edema 12 (14.8%), interstitial lung disease 1 (1.2%), COPD attack 28 (34.5%), malignant effusion 1 (1.2%), pneumonia 11 (13.5%). There was no statistically significant relationship between the clinical background of the patients and intubation outcome (p \u0026gt; 0.05). (Table 1)\u003c/p\u003e\n\u003cp\u003eWhen the patients' chronic diseases were evaluated, there were 59 (72.8%) with hypertension, 26 (32%) with diabetes mellitus, 22 (27.1%) with chronic heart failure, 24 (29.6%) with coronary artery disease, 6 (7.4%) with chronic kidney failure, and 41 (50.6%) with COPD or asthma. There were statistically significant differences among the patients with hypertension and CHF. The presence of hypertension was statistically significantly lower in the NIMV Intubation (+) group compared to the NIMV Intubation (-) group (p = 0.023), and the presence of CHF in the NIMV Intubation (+) group was also statistically significantly lower compared to the NIMV Intubation (-) group (p = 0.023). No differences were found in other chronic diseases. (Table 1)\u003c/p\u003e\n\u003cp\u003eThe oxygen saturation levels under masks of patients in the group that resulted in intubation were found to be 78.4±10.97, while in the group that did not result in intubation, it was 88.46±5.55, and it was found to be statistically significant that patients with more desaturation were intubated (p=0.0001). However, no statistically significant relationship was found between the number of breaths the patients took and the outcome of intubation (p=0.754). (Table 1)\u003c/p\u003e\n\u003cp\u003eWhen evaluating the RASS scale, which shows the level of agitation of patients, the non-intubated group was found to be 2.17±0.68, and the intubated group was 2.66±0.73, and it was found to be statistically significant that NIMV intubation (+) group was higher (p=0.003). (Table 1)\u003c/p\u003e\n\u003cp\u003eThe second dose of ketamine was found to be statistically significantly higher in the NIMV intubation (+) group compared to the NIMV intubation (-) group after the first dose of ketamine was found to be insufficient (p=0.0001). All patients who required a second dose of ketamine were intubated, while only one patient was intubated without a second dose of ketamine. No second dose of ketamine was needed for all patients who did not result in intubation.\u003c/p\u003e\n\u003cp\u003eThe adverse effects of ketamine after administration were as follows:\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003eThree or more consecutive ventricular ectopic beats in ECG\u003c/li\u003e\n \u003cli\u003eHypersalivation\u003c/li\u003e\n \u003cli\u003eA decrease in systolic blood pressure of more than 20 mm Hg\u003c/li\u003e\n \u003cli\u003eAn increase in heart rate of 20 or more\u0026nbsp;\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eOf the 81 patients included in the study, the adverse effects of ketamine were detected in 8 (9.8%). The effect of hypersalivation was only seen in 1 (1.2%) patient. No statistically significant difference was observed in the distribution of the presence of ketamine adverse effects between the NIMV intubation (-) and NIMV intubation (+) groups (p=0.178). (Table 2)\u003c/p\u003e\n\u003cp\u003eA logistic regression analysis was conducted to determine the factors affecting NIMV intubation using the HT, KKY, Mask-under SpO2, and RASS Agitation Score variables. The HT (p=0.627) and KKY (p=0.943) variables were found to be insignificant, while the decrease in Mask-under SpO2 (p=0.0001) and the increase in RASS Agitation Score (p=0.033) were identified as the factors affecting NIMV intubation with NIMV application. (Table 3)\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eNon-invasive ventilation (NIMV) has been shown to be effective in avoiding intubation and improving survival in patients with acute hypoxemic respiratory failure compared to conventional oxygen therapy.[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] However, the patient's failure to adapt to mechanical ventilation or the occurrence of agitation due to respiratory distress can significantly reduce the success of NIMV. There are some case reports in the literature indicating that ketamine can be applied to patients who cannot tolerate NIMV due to agitation and success can be achieved .[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] In our study, similar success rates were observed in patients with exacerbation of COPD, decompensated heart failure, hypertensive pulmonary edema, and pneumonia. The reason for the preference of ketamine over other sedatives may be explained by its anxiolytic effect and the absence of negative effects on respiration and hemodynamics.\u003c/p\u003e \u003cp\u003eThe clinical cases mentioned in the case reports in the literature are asthma attack and acute cardiogenic pulmonary edema [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. At present, ketamine is used at the Emergency Medicine Clinic of for procedural sedation, deep sedation for intubation preparation, and sedation of agitated patients who cannot tolerate non-invasive mechanical ventilation. In the meta-analysis performed, serious cardiopulmonary adverse effects were found to be quite rare among the adverse effects of ketamine, and in our study, no serious adverse effects were observed. The frequency of adverse effects was found to be 9.8% and was found to be in line with the literature.[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] However, higher doses may lead to the occurrence of dissociative effects, which are not suitable for ventilator compatibility, and invasive ventilation may be required. Hypersalivation effect, which can disrupt ventilation compatibility, was observed in only one patient, and did not result in intubation. The effect, which was only detected in 1.2%, was not considered appropriate to avoid ketamine in NIMV applications. The dissociative effect of ketamine starts at doses above 1-1.5 mg/kg. The first and second doses of 0.5 mg/kg of ketamine were administered to patients included in the study, so no dissociative effect was observed. Other side effects detected included a systolic blood pressure increase of 20 mm Hg or more, 3 or more consecutive ventricular ectopic beats on the ECG, and a heart peak rate increase of 20 or more, which did not affect the patient's outcome with intubation. The side effects caused by ketamine at low doses are not sufficient to avoid NIMV.[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eNIMV cannot be initiated unless the required comfort and ventilation compliance are achieved, and if adequate oxygenation cannot be achieved, direct invasive ventilation is required. The Richmond Agitation-Sedation Scale is used to measure the levels of agitation and sedation in the patient. In critically ill patients with acute respiratory failure, the scoring used must be rapid, reliable, and repeatable. In a comparative study with the Ramsay Sedation Scale, the Richmond Agitation-Sedation Scale (RASS) was found to be more reliable.[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] According to this scoring system, patients with an agitation level of +\u0026thinsp;2 or higher were included in the study and patients with high levels of agitation in this scoring resulted in more intubation. Most of the patients who resulted in intubation had to be given a second dose of ketamine. This is likely since the agitation levels were higher. Moreover, considering that the need for a second dose of ketamine arose from agitation levels or inability to achieve sufficient compliance with NIMV using the first sedation dose, it may be more appropriate to directly proceed to invasive ventilation instead of waiting for the second ketamine dose for these patients. A study conducted on high-flow nasal oxygen showed that the failure of HFNO increased mortality by causing a delay in intubation, which is why continuing NIMV insufficiency in a patient by waiting for a second dose of ketamine and not providing adequate oxygen support for a longer period may negatively impact the outcome.[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eOur study included 81 patients who were unable to tolerate NIMV due to agitation and would have required invasive mechanical ventilation if ketamine was not administered. In 43.2% of this patient group, intubation was avoided. A widespread epidemiological study in the United States has shown that mechanical ventilation has a relationship with mortality and is a significant economic burden on the health system.[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] In the study group of hospitalized patients, 2.7% required mechanical ventilation and the total cost was estimated to be 2.7\u0026nbsp;billion US dollars. It is recommended to implement cost-saving measures. In a study on complications related to mechanical ventilation, 9.3% of 597 patients were found to have ventilator-associated pneumonia.[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] The expected mortality rate for ventilator-associated pneumonia is in the 10% range and is expected to be higher in critically ill patients. Although the patient group unable to tolerate NIMV due to agitation is small, using ketamine to prevent the transition to invasive ventilation may be significant in terms of both cost and patient survival.[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eBetween 40\u0026ndash;60% FiO2 can be delivered with simple mask oxygenation. Despite this oxygen support, lower So2 values were found in the group of intubated patients. In this context, sedating critically ill patients with lower oxygen saturation using ketamine has made it more difficult to avoid intubation. When the predictors of intubation were evaluated in a study, it was shown that having a high respiratory rate under conventional oxygen support increases the likelihood of ending with intubation.[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] In our study, the administration of ketamine did not result in a statistically significant difference in the incidence of intubation outcomes as judged by the respiratory rate. This could be attributed to the fact that all the patients included in the study were monitored and the increase in respiratory rate in the group of patients with more than 25 breaths per minute may not be related to the outcome of intubation. The study did not find a statistically significant difference in the intubation outcomes of patients admitted to the emergency department based on their presenting clinical features. A meta-analysis study evaluated the relationship between non-invasive mechanical ventilation (NIMV) and mortality in acute respiratory failure, including 25 randomized controlled trials with a total of 3804 patients.[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] Studies have shown that there is a significant decrease in mortality compared to standard oxygen support, regardless of the presenting clinical severity. Offering non-invasive mechanical ventilation (NIMV) opportunity to patients prior to intubation can be positive in terms of patient survival, regardless of the referral clinics. The literature also demonstrates the positive effect of NIMV implementation on chronic respiratory failure in a significant portion of patients, which is mainly made up of exacerbation of chronic obstructive pulmonary disease (COPD) patients in both groups.[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eWhen evaluating chronic illnesses, it has been shown through logistic regression analysis that the presence of hypertension and congestive heart failure does not significantly affect the rate of intubation outcome. No significant relationship has been found between other chronic illnesses and intubation outcome. This suggests that in patients with acute respiratory failure, the administration of ketamine may be beneficial in avoiding intubation, regardless of the patient's known chronic illnesses. When compared to other sedative agents used during non-invasive mechanical ventilation (NIMV), ketamine has been found to be more effective than midazolam, propofol, and the opioid group, but less effective than dextromethorphan.[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/p\u003e \u003cdiv id=\"Sec21\" class=\"Section2\"\u003e \u003ch2\u003eLIMITATIONS\u003c/h2\u003e \u003cp\u003eIt is not sufficient to definitively state that ketamine is a suitable sedative agent for NIMVM tolerance. Its efficacy can be better demonstrated through larger-scale studies in the future. The exclusion of patients who used other sedative agents for NIMV agitation creates a limitation in the evaluation of ketamine compared to other agents. The relationship between ketamine administration in NIMV non-compliance and intubation has been discussed with articles available, due to the lack of sufficient prospective randomized studies investigating the issue.\u003c/p\u003e \u003c/div\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eIn patients with acute respiratory failure, agitation can disrupt NIMV compliance, but a proper sedative agent can help ensure NIMV compliance in a significant proportion of this patient group, avoiding the need for invasive mechanical ventilation. Considering the known effects of ketamine in this regard, it may be considered as a suitable agent. Given that ketamine applications at doses greater than 0.5 mg/kg do not have an impact on ending intubation, delaying invasive mechanical ventilation with a second dose of ketamine may not be appropriate. To reduce the cost of invasive mechanical ventilation and its adverse effects on patient outcome, ketamine for sedation may be a suitable option for strategies aimed at mitigating these outcomes.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eED: Emergency Department\u003c/p\u003e\n\u003cp\u003eNIMV: Non-invasive mechanical ventilation\u003c/p\u003e\n\u003cp\u003eIV: Invasive ventilation\u003c/p\u003e\n\u003cp\u003eIMV: Invasive mechanical ventilation\u003c/p\u003e\n\u003cp\u003eRASS: Richmond Agitation Sedation Scale\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate\u003c/strong\u003e \u0026ndash; A detailed written patient consent statement was obtained.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical Approval\u003c/strong\u003e \u0026ndash; İstanbul Medeniyet University G\u0026ouml;ztepe Prof. Dr. S\u0026uuml;leyman City Hospital Ethical Comitee of Clinical Reseraches\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDate: 17.08.2022 No: 2022/0489\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere is no sponsor and no funding to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCN: Conceptualization (lead); writing \u0026ndash; original draft (lead); formal analysis (lead); writing \u0026ndash; review and editing (equal).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eGAS: Software (lead); writing \u0026ndash; review, and editing (equal).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFA: Methodology (lead); writing \u0026ndash; review, and editing (equal).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026Ouml;FG: Methodology (lead); writing \u0026ndash; review, and editing (equal).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eKOD: Methodology (lead); writing \u0026ndash; review, and editing (equal).\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eYeow M-E, Santanilla JI (2008) Noninvasive positive pressure ventilation in the emergency department. Emerg Med Clin North Am 26:835\u0026ndash;847, x. https://doi.org/10.1016/j.emc.2008.04.005\u003c/li\u003e\n \u003cli\u003eWysocki M, Antonelli M (2001) Noninvasive mechanical ventilation in acute hypoxaemic respiratory failure. European Respiratory Journal 18:209\u0026ndash;220\u003c/li\u003e\n \u003cli\u003eGreen SM, Roback MG, Kennedy RM, Krauss B (2011) Clinical practice guideline for emergency department ketamine dissociative sedation: 2011 update. Ann Emerg Med 57:449\u0026ndash;461. https://doi.org/10.1016/j.annemergmed.2010.11.030\u003c/li\u003e\n \u003cli\u003eEly EW, Truman B, Shintani A, et al (2003) Monitoring Sedation Status Over Time in ICU Patients: Reliability and Validity of the Richmond Agitation-Sedation Scale (RASS). JAMA 289:2983. https://doi.org/10.1001/jama.289.22.2983\u003c/li\u003e\n \u003cli\u003eHillberg RE, Johnson DC (1997) Noninvasive ventilation. N Engl J Med 337:1746\u0026ndash;1752. https://doi.org/10.1056/NEJM199712113372407\u003c/li\u003e\n \u003cli\u003eKiureghian E, Kowalski JM (2015) Intravenous ketamine to facilitate noninvasive ventilation in a patient with a severe asthma exacerbation. The American Journal of Emergency Medicine 33:1720.e1-1720.e2. https://doi.org/10.1016/j.ajem.2015.03.066\u003c/li\u003e\n \u003cli\u003eVerma A, Snehy A, Vishen A, et al (2019) Ketamine Use allows Noninvasive Ventilation in Distressed Patients with Acute Decompensated Heart Failure. Indian J Crit Care Med 23:191\u0026ndash;192. https://doi.org/10.5005/jp-journals-10071-23153\u003c/li\u003e\n \u003cli\u003eStrayer RJ, Nelson LS (2008) Adverse events associated with ketamine for procedural sedation in adults. Am J Emerg Med 26:985\u0026ndash;1028. https://doi.org/10.1016/j.ajem.2007.12.005\u003c/li\u003e\n \u003cli\u003eOzyilmaz E, Ugurlu AO, Nava S (2014) Timing of noninvasive ventilation failure: causes, risk factors, and potential remedies. BMC Pulmonary Medicine 14:19. https://doi.org/10.1186/1471-2466-14-19\u003c/li\u003e\n \u003cli\u003eRasheed AM, Amirah MF, Abdallah M, et al (2019) Ramsay Sedation Scale and Richmond Agitation Sedation Scale: A Cross-sectional Study. Dimensions of Critical Care Nursing 38:90\u0026ndash;95. https://doi.org/10.1097/DCC.0000000000000346\u003c/li\u003e\n \u003cli\u003ePerkins GD, Ji C, Connolly BA, et al (2022) Effect of Noninvasive Respiratory Strategies on Intubation or Mortality Among Patients With Acute Hypoxemic Respiratory Failure and COVID-19: The RECOVERY-RS Randomized Clinical Trial. JAMA 327:546\u0026ndash;558. https://doi.org/10.1001/jama.2022.0028\u003c/li\u003e\n \u003cli\u003eWunsch H, Linde-Zwirble WT, Angus DC, et al (2010) The epidemiology of mechanical ventilation use in the United States*. Critical Care Medicine 38:1947\u0026ndash;1953. https://doi.org/10.1097/CCM.0b013e3181ef4460\u003c/li\u003e\n \u003cli\u003eKlompas M, Khan Y, Kleinman K, et al (2011) Multicenter Evaluation of a Novel Surveillance Paradigm for Complications of Mechanical Ventilation. PLOS ONE 6:e18062. https://doi.org/10.1371/journal.pone.0018062\u003c/li\u003e\n \u003cli\u003ePapazian L, Klompas M, Luyt C-E (2020) Ventilator-associated pneumonia in adults: a narrative review. Intensive Care Med 46:888\u0026ndash;906. https://doi.org/10.1007/s00134-020-05980-0\u003c/li\u003e\n \u003cli\u003eFrat J-P, Ragot S, Coudroy R, et al (2018) Predictors of Intubation in Patients With Acute Hypoxemic Respiratory Failure Treated With a Noninvasive Oxygenation Strategy*. Critical Care Medicine 46:208\u0026ndash;215. https://doi.org/10.1097/CCM.0000000000002818\u003c/li\u003e\n \u003cli\u003eFerreyro BL, Angriman F, Munshi L, et al (2020) Association of Noninvasive Oxygenation Strategies With All-Cause Mortality in Adults With Acute Hypoxemic Respiratory Failure: A Systematic Review and Meta-analysis. JAMA 324:57\u0026ndash;67. https://doi.org/10.1001/jama.2020.9524\u003c/li\u003e\n \u003cli\u003eKolodziej MA, Jensen L, Rowe B, Sin D (2007) Systematic review of noninvasive positive pressure ventilation in severe stable COPD. European Respiratory Journal 30:293\u0026ndash;306. https://doi.org/10.1183/09031936.00145106\u003c/li\u003e\n \u003cli\u003eLongrois D, Conti G, Mantz J, et al (2014) Sedation in non-invasive ventilation: do we know what to do (and why)? Multidiscip Respir Med 9:56. https://doi.org/10.1186/2049-6958-9-56\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1: Demographic structures of patients, chronic diseases, other findings and their relationship with intubation\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"653\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo intubation\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003en :46 (56.8%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eIntubation\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003en:35 (43.2%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003ep\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e75.93\u0026plusmn;11.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e78.51\u0026plusmn;12.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.336*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.2052067381317%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eGender\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.15926493108729%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMale\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\" valign=\"top\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\" valign=\"top\"\u003e\n \u003cp\u003e39.13%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\" valign=\"top\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\" valign=\"top\"\u003e\n \u003cp\u003e48.57%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.395+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"47.2972972972973%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eFemale\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.26126126126126%\" valign=\"top\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.09009009009009%\" valign=\"top\"\u003e\n \u003cp\u003e60.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.26126126126126%\" valign=\"top\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.09009009009009%\" valign=\"top\"\u003e\n \u003cp\u003e51.43%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.2052067381317%\" rowspan=\"7\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePresent clinical situation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.15926493108729%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAsthma Attack\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\" valign=\"top\"\u003e\n \u003cp\u003e4.35%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\" valign=\"top\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"top\"\u003e\n \u003cp\u003e0.503ǂ\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.338582677165356%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDecompansated kardiac failure\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\" valign=\"top\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\" valign=\"top\"\u003e\n \u003cp\u003e41,30%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\" valign=\"top\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\" valign=\"top\"\u003e\n \u003cp\u003e20.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.598425196850394%\" valign=\"top\"\u003e\n \u003cp\u003e0.073+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.338582677165356%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHypertensive pulmonary edema\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\" valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\" valign=\"top\"\u003e\n \u003cp\u003e8.70%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\" valign=\"top\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\" valign=\"top\"\u003e\n \u003cp\u003e22.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.598425196850394%\" valign=\"top\"\u003e\n \u003cp\u003e0.144+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.338582677165356%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eInterstitial lung disease\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\" valign=\"top\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\" valign=\"top\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\" valign=\"top\"\u003e\n \u003cp\u003e2.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.598425196850394%\" valign=\"top\"\u003e\n \u003cp\u003e0.890ǂ\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.338582677165356%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCOPD Attack\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\"\u003e\n \u003cp\u003e32.61%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\"\u003e\n \u003cp\u003e37.14%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.598425196850394%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.849\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.338582677165356%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMalignant effusion\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\"\u003e\n \u003cp\u003eone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\"\u003e\n \u003cp\u003e2.17%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.598425196850394%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.890ǂ\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"41.338582677165356%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ePneumonia\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\"\u003e\n \u003cp\u003e10.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.84251968503937%\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.188976377952756%\"\u003e\n \u003cp\u003e17.14%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.598425196850394%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.625+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e82.61%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e60.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.023+\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eDM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e32.61%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e31.43%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.910+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCHF\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e36.96%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e14.29%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.023+\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e32.61%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e25.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.501+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eKRG\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e8.70%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e5.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.612+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCOPD+Asthma\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e52.17%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e48.57%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.748+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCVO\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e10.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e20.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.252+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eCKD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e4.35%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e8.57%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.434+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAlzheimer\u0026apos;s\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e6.52%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003eone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e2.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.451ǂ\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eMalignity\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e6.52%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e5.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.881+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eUnder The Mask Spo2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e88.46\u0026plusmn;5.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e78.4\u0026plusmn;10.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0001*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eRespiration Rate\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e38.28\u0026plusmn;4.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e38.63\u0026plusmn;5.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.754*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"54.364471669218986%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eRASS Agitation Score\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e2.17\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.91730474732006%\" colspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e2.66\u0026plusmn;0.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.003*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.2052067381317%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ea second administration of ketamine necessary?\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.15926493108729%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003eone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e2.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" rowspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0001\u0026nbsp;\u003c/strong\u003eǂ\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"47.2972972972973%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYes\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.26126126126126%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.09009009009009%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.26126126126126%\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.09009009009009%\"\u003e\n \u003cp\u003e97.14%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"22.2052067381317%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdverse effect of ketamine\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"32.15926493108729%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e84.78%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.656967840735069%\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.260336906584993%\"\u003e\n \u003cp\u003e94.29%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.800918836140887%\" rowspan=\"2\" valign=\"bottom\"\u003e\n \u003cp\u003e0.178+\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"47.2972972972973%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eYes\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.26126126126126%\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.09009009009009%\"\u003e\n \u003cp\u003e15.22%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.26126126126126%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.09009009009009%\"\u003e\n \u003cp\u003e5.71%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"7\"\u003e\n \u003cp\u003e\u003cstrong\u003e*Independent t test + Chi-square test ǂFisher\u0026apos;s Reality Test\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eTable 2: Relation of Adverse Effect of Ketamine with Intubation\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"517\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.116279069767444%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdverse effect of ketamine\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"31.007751937984494%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNIMV Intubation (-) n:46\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"28.875968992248062%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eNIMV Intubation (+) n:35\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.116279069767444%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e3 consecutive VES on ECG\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.372093023255815%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.635658914728683%\"\u003e\n \u003cp\u003e33.33%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.922480620155039%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.953488372093023%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.116279069767444%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003ehypersalivation\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.372093023255815%\"\u003e\n \u003cp\u003eone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.635658914728683%\"\u003e\n \u003cp\u003e16.67%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.922480620155039%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.953488372093023%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.116279069767444%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eBlood Pressure 20 mmHG drop\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.372093023255815%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.635658914728683%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.922480620155039%\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.953488372093023%\"\u003e\n \u003cp\u003e100.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40.116279069767444%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eHR 20 increase\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.372093023255815%\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"17.635658914728683%\"\u003e\n \u003cp\u003e50.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.922480620155039%\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.953488372093023%\"\u003e\n \u003cp\u003e0.00%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3: Logistic Regression Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"378\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"46.82539682539682%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eOR\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.312169312169313%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e95% OR\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003ep\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"46.82539682539682%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eHT\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.312169312169313%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.36-5.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.627\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"46.82539682539682%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eCHF\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e1.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.312169312169313%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.27-4.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e0.943\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"46.82539682539682%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpO2 under the mask\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.86*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.312169312169313%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.79-0.94*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.0001*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"46.82539682539682%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003eRASS Agitation Score\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e2.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.312169312169313%\" valign=\"bottom\"\u003e\n \u003cp\u003e1.08-5.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"16.93121693121693%\" valign=\"bottom\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.033*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-emergency-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"emmd","sideBox":"Learn more about [BMC Emergency Medicine](http://bmcemergmed.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/emmd","title":"BMC Emergency Medicine","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Ketamine, Psychomotor Agitation, Noninvasive Ventilation, Respiratory Insufficiency","lastPublishedDoi":"10.21203/rs.3.rs-3937336/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3937336/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eBackground\u003c/b\u003e\u003c/p\u003e \u003cp\u003eIn patients presenting to the emergency department (ED) with acute respiratory failure, non-invasive mechanical ventilation (NIMV) is applied when conventional oxygen support is not sufficient. Patients who are agitated often have very low NIMV compliance and a transition to invasive mechanical ventilation (IMV) is often required. To avoid IMV, a suitable sedative agent can be utilized. The aim of this research is to investigate the relationship between ketamine administration to patients who are non-compliant with NIMV due to agitation and the outcome of their intubation.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThis retrospective study included patients with acute respiratory failure who were admitted to the ED from 2021 to 2022 and used Richmond Agitation Sedation Scale (RASS) for identify agitation level of patients. The relationship between ketamine administration in this patient group and NIMV compliance and intubation outcome was evaluated.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eA total of 81 patients, including 35 (43.2%) men and 46 (56.8%) women, were included in the study. Of these patients, 46 (56.8%) were intubated despite ketamine administration, while 35 (43.2%) were compliant with NIMV and were not intubated. When evaluating the RASS, which shows the agitation levels of the patients, the non-intubated group was found to be 2.17\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68, while the intubated group was 2.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.73, and it was statistically significant that the NIMV intubated group was higher (p\u0026thinsp;=\u0026thinsp;0.003).\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThis study showed that agitation can impair NIMV compliance in patients with acute respiratory failure. However, a significant proportion of this patient group can be avoided through IMV with proper sedative agents.\u003c/p\u003e","manuscriptTitle":"The Effectiveness of Ketamine on Non-invasive Ventilation Compliance in Acute Respiratory Failure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-09 05:09:37","doi":"10.21203/rs.3.rs-3937336/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-04-03T21:40:59+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-03-27T18:50:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"18fc6f34-ab2e-490b-ad98-f752e8dbedc9","date":"2024-03-19T14:39:21+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-03-18T10:43:25+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-02-16T10:57:04+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-02-16T10:55:28+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-02-16T10:55:28+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Emergency Medicine","date":"2024-02-07T15:36:47+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-emergency-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"emmd","sideBox":"Learn more about [BMC Emergency Medicine](http://bmcemergmed.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/emmd","title":"BMC Emergency Medicine","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2636523f-e450-4491-8b39-0123d3091cfd","owner":[],"postedDate":"February 9th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-10-14T16:01:23+00:00","versionOfRecord":{"articleIdentity":"rs-3937336","link":"https://doi.org/10.1186/s12873-024-01100-z","journal":{"identity":"bmc-emergency-medicine","isVorOnly":false,"title":"BMC Emergency Medicine"},"publishedOn":"2024-10-11 15:57:34","publishedOnDateReadable":"October 11th, 2024"},"versionCreatedAt":"2024-02-09 05:09:37","video":"","vorDoi":"10.1186/s12873-024-01100-z","vorDoiUrl":"https://doi.org/10.1186/s12873-024-01100-z","workflowStages":[]},"version":"v1","identity":"rs-3937336","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3937336","identity":"rs-3937336","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}