Association of ketamine use with lower risks of post-intubation hypotension in hemodynamically-unstable patients in the emergency department

Positive effects of low-dose S-ketamine on preventing myocardial injury after thoracoscopic lobectomy in patients aged 70 to 85

OBJECTIVE

To investigate the effects of low-dose S-ketamine on marker of myocardial injury (BNP, hs-cTnT and HFABP) after thoracoscopic lobectomy in patients aged 70 to 85.

METHODS

One hundred patients (four cases excluded) aged 70-85 years, with body mass index 18-24 kg·m-2 and American Society of Anesthesiologists physical status II-III, scheduled for elective lobectomy from April 2022 to April 2023, were selected. The patients were divided into two groups by a random number table method, namely, the low-dose S-ketamine combined with GDFT group (group S) and the control group (group C), with 48 cases in each group. In group S, a low dose of S-ketamine (0.2 mg/kg) was given 1 min before intubation, and the maintenance dose was 0.12 mg·kg-1·h-1. Fluid therapy, guided by cardiac index (CI), changes in stroke volume (△SV), and other dynamic indicators, was used for rehydration during the operation. Group C was given the same amount of normal saline (0.2 mg/kg) 1 min before intubation, and the same rehydration therapy was adopted during the operation. The mean arterial pressure (MAP) and heart rate (HR) of the two groups were observed and recorded immediately after entering the operating room (T0), immediately after intubation (T1), immediately after the beginning of one-lung ventilation (OLV) (T2), immediately after the beginning of surgery (T3), immediately after the end of OLV (T4), and at the end of surgery (T5). The intraoperative fluid intake and output and the use of vasoactive drugs were recorded. The plasma levels of heart-type fatty acid-binding protein (HFABP), high-sensitivity troponin T (hs-cTnT), brain natriuretic peptide (BNP), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α) were recorded 24 h before operation and 24 and 48 h after operation. Visual analogue scale (VAS) pain scores at rest were recorded at 2 (V1), 6 (V2), 12 (V3), 24 (V4), and 48 h (V5) after operation, and the occurrence of myocardial ischemia during hospitalization was noted.

RESULTS

Compared with group C, MAP was significantly higher at T1-T5 in group S (P < 0.05), and the plasma concentrations of IL-6, IL-8, TNF-α, BNP, hs-cTnT, and HFABP were significantly lower at 24 and 48 h after operation (P < 0.05). The VAS pain scores at 2, 6, 12, 24, and 48 h after operation, the number of effective patient-controlled intravenous analgesia (PCIA) compressions, and the total number of PCIA compressions within 48 h after operation were significantly decreased (P < 0.05). Compared with group C, The hospitalization days, and the incidence of postoperative myocardial ischemia in group S were lower (P < 0.05). There were no significant intergroup differences in urine volume, extubation time, the incidence of postoperative atrial fibrillation, bleeding volume, colloid infusion volume, total fluid infusion volume, and the incidence of rescue analgesia.

CONCLUSIONS

Low-dose S-ketamine can reduce the levels of hs-cTnT, HFABP, and BNP in older patients after pulmonary lobectomy, which has a positive effect on preventing myocardial injury.

TRIAL REGISTRATION

This study was registered on CHICTR (registration No. ChiCTR2300074475). Date of registration: 08/08/2023.

Ketamine Use in the Intubation of Critically Ill Children with Neurological Indications: A Multicenter Retrospective Analysis

BACKGROUND

Ketamine has traditionally been avoided for tracheal intubations (TIs) in patients with acute neurological conditions. We evaluate its current usage pattern in these patients and any associated adverse events.

METHODS

We conducted a retrospective observational cohort study of critically ill children undergoing TI for neurological indications in 53 international pediatric intensive care units and emergency departments. We screened all intubations from 2014 to 2020 entered into the multicenter National Emergency Airway Registry for Children (NEAR4KIDS) registry database. Patients were included if they were under the age of 18 years and underwent TI for a primary neurological indication. Usage patterns and reported periprocedural composite adverse outcomes (hypoxemia < 80%, hypotension/hypertension, cardiac arrest, and dysrhythmia) were noted.

RESULTS

Of 21,562 TIs, 2,073 (9.6%) were performed for a primary neurological indication, including 190 for traumatic brain injury/trauma. Patients received ketamine in 495 TIs (23.9%), which increased from 10% in 2014 to 41% in 2020 (p < 0.001). Ketamine use was associated with a coindication of respiratory failure, difficult airway history, and use of vagolytic agents, apneic oxygenation, and video laryngoscopy. Composite adverse outcomes were reported in 289 (13.9%) Tis and were more common in the ketamine group (17.0% vs. 13.0%, p = 0.026). After adjusting for location, patient age and codiagnoses, the presence of respiratory failure and shock, difficult airway history, provider demographics, intubating device, and the use of apneic oxygenation, vagolytic agents, and neuromuscular blockade, ketamine use was not significantly associated with increased composite adverse outcomes (adjusted odds ratio 1.34, 95% confidence interval CI 0.99-1.81, p = 0.057). This paucity of association remained even when only neurotrauma intubations were considered (10.6% vs. 7.7%, p = 0.528).

CONCLUSIONS

This retrospective cohort study did not demonstrate an association between procedural ketamine use and increased risk of peri-intubation hypoxemia and hemodynamic instability in patients intubated for neurological indications.

A Nomogram Model for Post-Intubation Hypotension in Patients with Severe Pneumonia in the Emergency Department

Background

Post-intubation hypotension (PIH) frequently occurs in the management of critically ill patients and is associated with prognosis. The study aimed to construct a prediction model for PIH events by analyzing risk factors in patients with severe pneumonia in the emergency department.

Methods

We retrospectively enrolled 572 patients with severe pneumonia diagnosed in the emergency department of West China Hospital of Sichuan University. Five hundred patients with severe pneumonia who underwent endotracheal intubation were included in the study. All patients were randomized according to 7:3 and divided into a training cohort (n=351) and a validation cohort (n=149). Risk factors for PIH were analyzed using Least Absolute Shrinkage and Selection Operator (LASSO) and multivariable logistic regression. Calibration curves, receiver operating characteristic (ROC) curve, and decision curve analysis were applied to assess the predictive model's fitness, discrimination, and clinical utility.

Results

A total of 500 patients with severe pneumonia who underwent endotracheal intubation were enrolled in this study, and PIH occurred in 234 (46.8%) of these patients. Age, heart rate, systolic blood pressure, chronic obstructive pulmonary disease, acute physiology and chronic health evaluation II score, and induction agent use were identified as significant risk factors for the occurrence of PIH. Additionally, the body mass index was the opposite of the above. The area under the ROC curve (AUC) for the model was 0.856 (95% CI, 0.818-0.894) in the training cohort and 0.849 (95% CI, 0.788-0.910) in the validation cohort. The nomogram model was validated and demonstrated good calibration and high net clinical benefit. Finally, to facilitate application by clinicians, an online server has been set up which can be accessed free of charge via the website https://chinahospitals.shinyapps.io/DynNomapp/.

Conclusion

The nomogram is used for individualized prediction of patients with severe pneumonia prior to intubation and is simple to perform with high clinical value.

Clinical outcomes after a single induction dose of etomidate versus ketamine for emergency department sepsis intubation: a randomized controlled trial

Patients with sepsis often require emergency intubation. In emergency departments (EDs), rapid-sequence intubation with a single-dose induction agent is standard practice, but the best choice of induction agent in sepsis remains controversial. We conducted a randomized, controlled, single-blind trial in the ED. We included septic patients who were aged at least 18 years and required sedation for emergency intubation. Patients were randomly assigned by a blocked randomization to receive 0.2-0.3 mg/kg of etomidate or 1-2 mg/kg of ketamine for intubation. The objectives were to compare the survival outcomes and adverse events after intubation between etomidate and ketamine. Two hundred and sixty septic patients were enrolled; 130 patients/drug arm whose baseline characteristics were well balanced at baseline. In the etomidate group, 105 patients (80.8%) were alive at 28 days, compared with 95 patients (73.1%) in the ketamine group (risk difference [RD], 7.7%; 95% confidence interval [CI], - 2.5 to 17.9%; P = 0.092). There was no significant difference in the proportion of patients who survived at 24 h (91.5% vs. 96.2%; P = 0.097) and survived at 7 days (87.7% vs. 87.7%; P = 0.574). A significantly higher proportion of the etomidate group needed a vasopressor within 24 h after intubation: 43.9% vs. 17.7%, RD, 26.2% (95% CI, 15.4 to 36.9%; P < 0.001). In conclusion, there were no differences in early and late survival rates between etomidate and ketamine. However, etomidate was associated with higher risks of early vasopressor use after intubation. Trial registration: The trial protocol was registered in the Thai Clinical Trials Registry (identification number: TCTR20210213001). Registered 13 February 2021-Retrospectively registered, https://www.thaiclinicaltrials.org/export/pdf/TCTR20210213001 .

Ketamine is not associated with more post-intubation hypotension than etomidate in patients undergoing endotracheal intubation

INTRODUCTION

Emergency department (ED) patients undergoing emergent tracheal intubation often have multiple physiologic derangements putting them at risk for post-intubation hypotension. Prior work has shown that post-intubation hypotension is independently associated with increased morbidity and mortality. The choice of induction agent may be associated with post-intubation hypotension. Etomidate and ketamine are two of the most commonly used agents in the ED, however, there is controversy regarding whether either agent is superior in the setting of hemodynamic instability. The goal of this study is to determine whether there is a difference in the rate of post-intubation hypotension who received either ketamine or etomidate for induction. Additionally, we provide a subgroup analysis of patients at pre-existing risk of cardiovascular collapse (identified by pre-intubation shock index (SI) > 0.9) to determine if differences in rates of post-intubation hypotension exist as a function of sedative choice administered during tracheal intubation in these high-risk patients. We hypothesize that there is no difference in the incidence of post-intubation hypotension in patients who receive ketamine versus etomidate.

METHODS

A retrospective cohort study was conducted on a database of 469 patients having undergone emergent intubation with either etomidate or ketamine induction at a large academic health system. Patients were identified by automatic query of the electronic health records from 1/1/2016-6/30/2019. Exclusion criteria were patients <18-years-old, tracheal intubation performed outside of the ED, incomplete peri-intubation vital signs, or cardiac arrest prior to intubation. Patients at high risk for hemodynamic collapse in the post-intubation period were identified by a pre-intubation SI > 0.9. The primary outcome was the incidence of post-intubation hypotension (systolic blood pressure < 90 mmHg or mean arterial pressure < 65 mmHg). Secondary outcomes included post-intubation vasopressor use and mortality. These analyses were performed on the full cohort and an exploratory analysis in patients with SI > 0.9. We also report adjusted odds ratios (aOR) from a multivariable logistic regression model of the entire cohort controlling for plausible confounding variables to determine independent factors associated with post-intubation hypotension.

RESULTS

A total of 358 patients were included (etomidate: 272; ketamine: 86). The mean pre-intubation SI was higher in the group that received ketamine than etomidate, (0.97 vs. 0.83, difference: -0.14 (95%, CI -0.2 to -0.1). The incidence of post-intubation hypotension was greater in the ketamine group prior to SI stratification (difference: -10%, 95% CI -20.9% to -0.1%). Emergency physicians were more likely to use ketamine in patients with SI > 0.9. In our multivariate logistic regression analysis, choice of induction agent was not associated with post-intubation hypotension (aOR 1.45, 95% CI 0.79 to 2.65). We found that pre-intubation shock index was the strongest predictor of post-intubation hypotension.

CONCLUSION

In our cohort of patients undergoing emergent tracheal intubation, ketamine was used more often for patients with an elevated shock index. We did not identify an association between the incidence of post-intubation hypotension and induction agent between ketamine and etomidate. Patients with an elevated shock index were at higher risk of cardiovascular collapse regardless of the choice of ketamine or etomidate.

Rapid sequence intubation and the role of the emergency medicine pharmacist: 2022 update

PURPOSE

The dosing, potential adverse effects, and clinical outcomes of the most commonly utilized pharmacologic agents for rapid sequence intubation (RSI) are reviewed for the practicing emergency medicine pharmacist (EMP).

SUMMARY

RSI is the process of establishing a safe, functional respiratory system in patients unable to effectively breathe on their own. Various medications are chosen to sedate and even paralyze the patient to facilitate an efficient endotracheal intubation. The mechanism of action and pharmacokinetic/pharmacodynamic profiles of these agents were described in a 2011 review. Since then, the role of the EMP as well as the published evidence regarding RSI agents, including dosing, adverse effects, and clinical outcomes, has grown. It is necessary for the practicing EMP to update previous practice patterns in order to continue to provide optimal patient care.

CONCLUSION

While the agents used in RSI have changed little, knowledge regarding optimal dosing, appropriate patient selection, and possible adverse effects continues to be gained. The EMP is a key member of the bedside care team and uniquely positioned to communicate this evolving data.

Association Between Repeated Tracheal Intubation Attempts and Adverse Events in Children in the Emergency Department

STUDY OBJECTIVES

Studies have shown that multiple intubation attempts are associated with a higher risk of intubation-related adverse events. However, little is known about the relationship in children in the emergency department (ED).

METHODS

This is an analysis of the data from 2 prospective, observational, multicenter registries of emergency airway management. The data were collected from consecutive patients who underwent emergency airway management in 19 EDs across Japan from March 2010 to November 2017. We included children 18 years or younger who underwent tracheal intubation in the ED. The primary exposure was the number of intubation attempts (1 vs ≥2). The primary outcome was an adverse event during or immediately after the intubation.

RESULTS

A total of 439 children were eligible for the analysis. Of 279 children with first-pass success, 24 children (9%) had an adverse event. By contrast, of 160 children with ≥2 intubation attempts, 50 children patients (31%) had an adverse event. In the unadjusted model, multiple intubation attempts were significantly associated with a higher rate of adverse events (unadjusted odds ratio, 4.83; 95% confidence interval, 2.57-9.06; P < 0.001). This association remained significant after adjusting for 7 potential confounders and patient clustering within the hospital (adjusted odds ratio, 4.49; 95% confidence interval, 2.36-8.53; P < 0.001). Similar associations were found across different age groups and among children without cardiac arrest (all, P < 0.05).

CONCLUSIONS

In this analysis of large prospective multicenter data, multiple intubation attempts were associated with a significantly higher rate of intubation-related adverse events in children in the ED.

Prehospital Drug Assisted Airway Management: An NAEMSP Position Statement and Resource Document

Airway management is a critical intervention for patients with airway compromise, respiratory failure, and cardiac arrest. Many EMS agencies use drug-assisted airway management (DAAM) - the administration of sedatives alone or in combination with neuromuscular blockers - to facilitate advanced airway placement in patients with airway compromise or impending respiratory failure who also have altered mental status, agitation, or intact protective airway reflexes. While DAAM provides several benefits including improving laryngoscopy and making insertion of endotracheal tubes and supraglottic airways easier, DAAM also carries important risks. NAEMSP recommends:DAAM is an appropriate tool for EMS clinicians in systems with clear guidelines, sufficient training, and close EMS physician oversight. DAAM should not be used in settings without adequate resources.EMS physicians should develop clinical guidelines informed by evidence and oversee the training and credentialing for safe and effective DAAM.DAAM programs should include best practices of airway management including patient selection, assessmenct and positioning, preoxygenation strategies including apneic oxygenation, monitoring and management of physiologic abnormalities, selection of medications, post-intubation analgesia and sedation, equipment selection, airway confirmation and monitoring, and rescue airway techniques.Post-DAAM airway placement must be confirmed and continually monitored with waveform capnography.EMS clinicians must have the necessary equipment and training to manage patients with failed DAAM, including bag mask ventilation, supraglottic airway devices and surgical airway approaches.Continuous quality improvement for DAAM must include assessment of individual and aggregate performance metrics. Where available for review, continuous physiologic recordings (vital signs, pulse oximetry, and capnography), audio and video recordings, and assessment of patient outcomes should be part of DAAM continuous quality improvement.

A specialized airway management team for COVID-19 patients: a retrospective study of the experience of two Canadian hospitals in Toronto

BACKGROUND

In the COVID-19 pandemic, an unprecedented number of individuals required endotracheal intubation. To safely face these challenges, expert intubation teams were formed in some institutions. Here, we report on the experience of emergency rapid intubation teams (ERITs) in two Canadian hospitals.

METHODS

We retrospectively collected data on all airway management procedures in confirmed or suspected COVID-19 patients performed by ERITs at two academic hospitals between 3 April and 17 June 2020. The co-primary outcomes were incidence of periprocedural adverse events (hypoxemia, hypotension, and cardiac arrest within 15 min of intubation) and first-attempt intubation success rate. Secondary outcomes included number of intubation attempts, device used to achieve successful airway management, and adherence to personal protective equipment (PPE) protocols.

RESULTS

During the study period, 123 patients were assessed for airway management, with 117 patients receiving airway interventions performed by the ERIT. The first-attempt success rate for intubation was 92%, and a videolaryngoscope was the final successful device in 93% of procedures. Hypoxemia (peripheral oxygen saturation [SpO₂] < 90%) occurred in 28 patients (24%) and severe hypoxemia (SpO₂ < 70%) occurred in ten patients (9%). Hypotension (systolic blood pressure [SBP] < 90 mm Hg) occurred in 37 patients (32%) and severe hypotension (SBP < 65 mm Hg) in 11 patients (9%). Adherence to recommended PPE use among providers was high.

CONCLUSION

In this cohort of critically ill patients with respiratory failure requiring time-sensitive airway management, specialized ERIT teams showed high rates of successful airway management with high adherence to PPE use. Hypoxemia and hemodynamic instability were common and should be anticipated within the first 15 min following intubation.

STUDY REGISTRATION

www.ClinicalTrials.gov (NCT04689724); registered 30 December 2020.

The association of ketamine induction with blood pressure changes in paramedic rapid sequence intubation of out-of-hospital traumatic brain injury

INTRODUCTION

Rapid sequence intubation (RSI) is used to secure the airway of traumatic brain injury (TBI) patients, with ketamine frequently used for induction. Studies show that ketamine-induction RSI might cause lower blood pressures when compared to etomidate. It is not clear if the results from that research can be extrapolated to systems that use different dosing regimens for ketamine RSI. Ambulance Victoria authorized the use of 1.5 mg/kg ketamine in January 2015 for head injury RSI induction by road-based paramedics. This study aims to examine whether systolic blood pressure changed when ketamine was introduced for prehospital head injury RSI.

METHODS

This study was a retrospective analysis of out-of-hospital suspected TBI that received RSI by paramedics. Our analysis employs an interrupted time-series analysis (ITSA), which is a quasi-experimental method that tested whether hypotension and systolic blood pressures changed after the switch to ketamine induction in 2015. This ITSA utilized an ordinary least squares regression on complete observations using Newey-West standard errors.

RESULTS

During the study period, paramedics performed RSI in 8,613 patients, and 1,759 (20.4%) had a TBI. Ketamine usage increased by 52.7% in January 2015 (p < 0.001) after road-based paramedics were authorized to use ketamine induction. This analysis found significant 5% increase in post-RSI hypotension (p = 0.046) after the introduction of ketamine, and thereafter the incidence of post-RSI hypotension increased steadily by 0.5% every 3 months (p = 0.004). Concurrently, changes in systolic blood pressure, as measured by the interval just before induction to the last measured on scene, show an average decrease of 7.8 mm Hg (p = 0.04) at the start of 2015 with the ketamine rollout.

CONCLUSIONS

This ITSA shows that postinduction hypotension and also decreases in systolic blood pressures became evident after the introduction of ketamine. Further research to investigate the association between ketamine induction and survival is needed.

Cardiovascular complications of prehospital emergency anaesthesia in patients with return of spontaneous circulation following medical cardiac arrest: a retrospective comparison of ketamine-based and midazolam-based induction protocols

BACKGROUND

Hypotension following intubation and return of spontaneous circulation (ROSC) after cardiac arrest is associated with poorer patient outcomes. In patients with a sustained ROSC requiring emergency anaesthesia, there is limited evidence to guide anaesthetic practice. At the Essex & Herts Air Ambulance Trust, a UK-based helicopter emergency medical service, we assessed the relative haemodynamic stability of two different induction agents for post-cardiac arrest medical patients requiring prehospital emergency anaesthesia (PHEA).

METHODS

We performed a retrospective database review over a 5-year period between December 2014 and December 2019 comparing ketamine-based and midazolam-based anaesthesia in this patient cohort. Our primary outcome was clinically significant hypotension within 30 min of PHEA, defined as a new systolic BP less than 90 mm Hg, or a 10% drop if less than 90 mm Hg before induction.

RESULTS

One hundred ninety-eight patients met inclusion criteria. Forty-eight patients received a ketamine-based induction, median dose (IQR) 1.00 (1.00-1.55) mg/kg, and a 150 midazolam-based regime, median dose 0.03 (0.02-0.04) mg/kg. Hypotension occurred in 54.2% of the ketamine group and 50.7% of the midazolam group (p=0.673). Mean maximal HRs within 30 min of PHEA were 119 beats/min and 122 beats/min, respectively (p=0.523). A shock index greater than 1.0 beats/min/mm Hg and age greater than 70 years were both associated with post-PHEA hypotension with ORs 1.96 (CI 1.02 to 3.71) and 1.99 (CI 1.01 to 3.90), respectively. Adverse event rates did not significantly differ between groups.

CONCLUSION

PHEA following a medical cardiac arrest is associated with potentially significant cardiovascular derangements when measured up to 30 min after induction of anaesthesia. There was no demonstrable difference in post-induction hypotension between ketamine-based and midazolam-based PHEA. Choice of induction agent alone is insufficient to mitigate haemodynamic disturbance, and alternative strategies should be used to address this.

Mapping haemodynamic changes with rapid sequence induction agents in the emergency department

OBJECTIVE

Patients intubated in the ED are at an increased risk of post-intubation hypotension. However, evidence regarding the most appropriate induction agent is lacking. The present study aims to describe and compare the haemodynamic effect of propofol, ketamine and thiopentone during rapid sequence induction.

METHODS

This is an observational study using data prospectively collected from the Australian and New Zealand Emergency Department Airway Registry between June 2012 and March 2019. The distribution of induction agents across medical and trauma patients were obtained with descriptive statistics. The relationship between induction agent, dose and change in pre- and post-intubation systolic blood pressure (SBP) was described using multivariable logistic regression. The SBP pre- and post-intubation was the primary measure of haemodynamic stability.

RESULTS

From the 5063 intubation episodes, 2229 met the inclusion criteria. Of those, 785 (35.2%) patients were induced with thiopentone, 773 (34.7%) with propofol and 671 (30.1%) with ketamine. Of the included population, 396 (17.8%) patients experienced a reduction in pre-intubation SBP exceeding 20%. Both propofol (P = 0.01) and ketamine (P = 0.01) had an independent and dose-dependent association with hypotension, noting that a higher proportion of patients induced with ketamine had a shock index exceeding 0.9.

CONCLUSION

Propofol was associated with post-intubation hypotension and it is recommended clinicians consider using the lowest effective dose to reduce this risk. Reflecting its perceived haemodynamic stability, patients who received ketamine were more likely to have a higher shock index; however, there was also an association with post-intubation hypotension.

Propofol, Ketamine, and Etomidate as Induction Agents for Intubation and Outcomes in Critically Ill Patients: A Retrospective Cohort Study

Propofol, ketamine, and etomidate are common anesthetic agents for induction of anesthesia in the ICU. The choice between these agents is complex and may not depend solely upon severity of illness.

OBJECTIVES

To evaluate the association between the administration of propofol, ketamine, and etomidate and ICU, hospital mortality, and length of stay.

DESIGN SETTING AND PARTICIPANTS

Retrospective single-center cohort study. ICUs in a tertiary medical center, between January 01, 2012, and December 31, 2017. Critically ill adult patients given a single IV anesthetic for intubation.

MAIN OUTCOME AND MEASURES

Primary outcomes were ICU and hospital mortality. Secondary outcomes were ICU- and hospital-free days through 28 days. An inverse probability of treatment weighed approach was used. The propensity score was estimated using a generalized logit model as a function of patient characteristics, admission source, ICU type, readmission status, length of ICU stays prior to intubation, and acute physiology score. Mortality outcomes were assessed with weighted logistic regression and -free days assessed by weighted linear regression with Bonferroni correction for pairwise comparisons.

RESULTS

Of 2,673 patients, 36% received propofol, 30% ketamine and 34% etomidate. Overall ICU and hospital mortality were 19% and 29%, respectively. Patients given ketamine had higher odds of ICU mortality (1.45; [95% CI, 1.07-1.94]; p = 0.015) and patients given etomidate had higher odds of ICU mortality (1.87; 1.40-2.49; p < 0.001), hospital mortality (1.43; 1.09-1.86; p = 0.009), and less ICU-free days (-2.10; -3.21 to -1.00; p < 0.001) than those given propofol. Patients given ketamine and etomidate had similar odds of hospital mortality (1.06; 0.80-1.42; p = 0.761) and similar hospital-free days (0.30; -0.81 to 1.40; p = 0.600).

CONCLUSIONS AND RELEVANCE

Compared with ketamine and etomidate, propofol was associated with better outcome in critically ill patients undergoing anesthesia for intubation. Even after adjusting for severity of illness prior to intubation, residual confounders cannot be excluded.

Prehospital Ketamine Use for Rapid Sequence Intubation: Are Higher Doses Associated With Adverse Events?

OBJECTIVE

Ketamine for rapid sequence intubation (RSI) is typically dosed at 1 to 2 mg/kg intravenously. The need to ensure dissociation during RSI led some to administer ketamine at doses greater than 2 mg/kg. This study assessed associations between ketamine dose and adverse events.

METHODS

This multisite, retrospective study included adult subjects undergoing RSI with intravenous ketamine. Subjects were categorized into 2 groups: a standard ketamine dose (≤ 2 mg/kg intravenously) or a high dose (> 2 mg/kg intravenously). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for adverse events.

RESULTS

Eighty subjects received standard-dose ketamine, and 50 received high-dose ketamine. The high-dose group had a significantly (P < .05) higher proportion of trauma patients, were younger, and had higher predose blood pressure compared with the standard-dose group. High-dose ketamine was associated with greater odds of adverse events including hypotension (OR = 7.0; 95% CI, 3.0-16.6), laryngospasm (OR = 10.8; 95% CI, 1.3-93.4), bradycardia (OR = 7.5; 95% CI, 1.5-36.6), repeat medications (OR = 12.9; 95% CI, 1.5-107.9), oxygen desaturation (OR = 6.0; 95% CI, 1.8-19.9), multiple attempts (OR = 3.2; 95% CI, 1.5-6.8%), and failed airway (OR = 3.6; 95% CI, 1.0-12.7).

CONCLUSION

Ketamine at higher doses was associated with increased odds of adverse events. Studies assessing adverse events of ketamine at lower than standard doses in shock patients are needed.

Sedation for Rapid Sequence Induction and Intubation of Neurologically Injured Patients

There are subtle physiologic and pharmacologic principles that should be understood for patients with neurologic injuries. These principles are especially true for managing patients with traumatic brain injuries. Prevention of hypotension and hypoxemia are major goals in the management of these patients. This article discusses the physiology, pitfalls, and pharmacology necessary to skillfully care for this subset of patients with trauma. The principles endorsed in this article are applicable both for patients with traumatic brain injury and those with spinal cord injuries.