Midazolam is more likely to cause hypotension than etomidate in emergency department rapid sequence intubation

Factors Associated with Postintubation Hypotension Among Patients with Suspected Sepsis in Emergency Department

Purpose

Postintubation hypotension (PIH) is a recognized complication that increases both in-hospital mortality and hospital length of stay. Sepsis is reportedly a factor associated with PIH. However, no study to date has examined which factors, including the intubation method, may be clinical predictors of PIH in patients with sepsis. This study aims to investigate factors associated with the occurrence of PIH in patients with suspected sepsis in emergency department.

Patients and Methods

This retrospective cross-sectional study was performed over a 5-year period (January 2013-December 2017) and involved patients with suspected sepsis who underwent endotracheal intubation in the emergency department of Ramathibodi Hospital. The patients were divided into those with and without PIH, and factors associated with the occurrence of PIH were analyzed. PIH was defined as any recorded systolic blood pressure of <90 mmHg within 60 minutes of intubation.

Results

In total, 394 patients with suspected sepsis were included. PIH occurred in 106 patients (26.9%) and was associated with increased in-hospital mortality (43.00% in the PIH group vs 31.25% in the non-PIH group, P = 0.034). Multivariable logistic regression showed that the factors associated with PIH were an age of ≥61 years (adjusted odds ratio [aOR] 2.25; 95% confidence interval [CI] 1.14-4.43; P = 0.019) and initial serum lactate concentration of >4.4 mmol/L (aOR 2.00; 95% CI 1.16-3.46; P = 0.013). Rapid sequence intubation and difference types of induction agents was unrelated to PIH.

Conclusion

Monitoring the development of PIH in patients with sepsis is essential because of its correlation with higher in-hospital mortality. This is particularly critical for older individuals and those with severe infections and high initial lactate concentrations.

Sedative Dose for Rapid Sequence Intubation and Postintubation Hypotension: Is There an Association?

STUDY OBJECTIVE

For patients with hemodynamic instability undergoing rapid sequence intubation, experts recommend reducing the sedative medication dose to minimize the risk of further hemodynamic deterioration. Scant data support this practice for etomidate and ketamine. We sought to determine if the dose of etomidate or ketamine was independently associated with postintubation hypotension.

METHODS

We analyzed data from the National Emergency Airway Registry from January 2016 to December 2018. Patients aged 14 years or older were included if the first intubation attempt was facilitated with etomidate or ketamine. We used multivariable modeling to determine whether drug dose in milligrams per kilogram of patient weight was independently associated with postintubation hypotension (systolic blood pressure < 100 mm Hg).

RESULTS

We analyzed 12,175 intubation encounters facilitated by etomidate and 1,849 facilitated by ketamine. The median drug doses were 0.28 mg/kg (interquartile range [IQR] 0.22 mg/kg to 0.32 mg/kg) for etomidate and 1.33 mg/kg (IQR 1 mg/kg to 1.8 mg/kg) for ketamine. Postintubation hypotension occurred in 1,976 patients (16.2%) who received etomidate and in 537 patients (29.0%) who received ketamine. In multivariable models, neither the etomidate dose (adjusted odds ratio [aOR] 0.95, 95% confidence interval [CI] 0.90 to 1.01) nor ketamine dose (aOR 0.97, 95% CI 0.81 to 1.17) was associated with postintubation hypotension. Results were similar in sensitivity analyses excluding patients with preintubation hypotension and including only patients intubated for shock.

CONCLUSION

In this large registry of patients intubated after receiving either etomidate or ketamine, we observed no association between the weight-based sedative dose and postintubation hypotension.

Pharmacotherapy optimization for rapid sequence intubation in the emergency department

PURPOSE

Rapid-sequence intubation (RSI) is the process of administering a sedative and neuromuscular blocking agent (NMBA) in rapid succession to facilitate endotracheal intubation. It is the most common and preferred method for intubation of patients presenting to the emergency department (ED). The selection and use of medications to facilitate RSI is critical for success. The purpose of this review is to describe pharmacotherapies used during the RSI process, discuss current clinical controversies in RSI medication selection, and review pharmacotherapy considerations for alternative intubation methods.

SUMMARY

There are several steps to the intubation process requiring medication considerations, including pretreatment, induction, paralysis, and post-intubation sedation and analgesia. Pretreatment medications include atropine, lidocaine, and fentanyl; but use of these agents in clinical practice has fallen out of favor as there is limited evidence for their use outside of select clinical scenarios. There are several options for induction agents, though etomidate and ketamine are the most used due to their more favorable hemodynamic profiles. Currently there is retrospective evidence that etomidate may produce less hypotension than ketamine in patients presenting with shock or sepsis. Succinylcholine and rocuronium are the preferred neuromuscular blocking agents, and the literature suggests minimal differences between succinylcholine and high dose rocuronium in first-pass success rates. Selection between the two is based on patient specific factors, half-life and adverse effect profiles. Finally, medication-assisted preoxygenation and awake intubation are less common methods for intubation in the ED but require different considerations for medication use.

AREAS FOR FUTURE RESEARCH

The optimal selection, dosing, and administration of RSI medications is complicated, and further research is needed in several areas. Additional prospective studies are needed to determine optimal induction agent selection and dosing in patients presenting with shock or sepsis. Controversy exists over optimal medication administration order (paralytic first vs induction first) and medication dosing in obese patients, but there is insufficient evidence to significantly alter current practices regarding medication dosing and administration. Further research examining awareness with paralysis during RSI is needed before definitive and widespread practice changes to medication use during RSI can be made.

Association of intraoperative dexmedetomidine use with postoperative hypotension in unilateral hip and knee arthroplasties: a historical cohort study

PURPOSE

Dexmedetomidine is frequently used as a sedative agent for orthopedic surgery patients undergoing total hip or knee arthroplasty. Although the benefits of dexmedetomidine are well described in the literature, there is also potential for harm, especially regarding the hemodynamic effects of dexmedetomidine in the postoperative setting.

METHODS

This historical cohort study included all primary unilateral total hip or knee arthroplasties conducted from April 2017 to February 2020 in a single, university-affiliated, tertiary care centre (Jewish General Hospital, Montreal, QC, Canada). We used multivariable logistic regression to analyze the predictors for postoperative hypotension, defined as a systolic blood pressure < 90 mm Hg or any systolic blood pressure while on a vasopressor infusion in the postanesthesia care unit. Models were validated using calibration and discrimination with bootstrapping technique.

RESULTS

One thousand five hundred and eighty-eight patients were included in this study. Postoperative hypotension occurred in 413 (26%) patients. Statistically significant predictors for postoperative hypotension included female sex (adjusted odds ratio [aOR], 3.24; 95% confidence interval [CI], 2.29 to 4.58), a history of transient ischemic attack or cerebrovascular accident (aOR, 1.97; 95% CI, 1.04 to 3.72), and intraoperative dexmedetomidine use (aOR, 2.61; 95% CI, 1.99 to 3.42). Moreover, the risk of postoperative hypotension was approximately two times higher than baseline, with a total intraoperative dexmedetomidine dose above 50 μg (relative risk, 1.99; 95% CI, 1.63 to 2.44; P < 0.001). A higher preoperative systolic blood pressure (aOR, 0.98; 95% CI, 0.97 to 0.99) was a protective factor for postoperative hypotension.

CONCLUSION

In this historical cohort study, dexmedetomidine was a strong risk factor for postoperative hypotension in total hip or knee arthroplasty patients. Dexmedetomidine, and particularly at high cumulative doses above 50 μg, should be administered judiciously in high-risk surgical patients to minimize the risk of postoperative hypotension.

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.

Risk Factors for Intravenous Propacetamol-Induced Blood Pressure Drop in the Neurointensive Care Unit: A Retrospective Observational Study

BACKGROUND

Intravenous propacetamol is commonly used to control fever and pain in neurocritically ill patients in whom oral administration is often difficult. However, several studies reported that intravenous propacetamol may cause blood pressure drop. Thus, we aimed to investigate the occurrence and risk factors for intravenous propacetamol-induced blood pressure drop in neurocritically ill patients.

METHODS

This retrospective study included consecutive patients who were administered intravenous propacetamol in a neurointensive care unit at a single tertiary academic hospital between April 2013 and June 2020. The exact timing of intravenous propacetamol administration was collected from a database of the electronic barcode medication administration system. Blood pressure drop was defined as a systolic blood pressure below 90 mm Hg or a decrease by 30 mm Hg or more. Blood pressure, pulse rate, and body temperature were collected at baseline and within 2 h after intravenous propacetamol administration. The incidence of blood pressure drop was evaluated, and multivariable logistic regression analysis was performed to identify risk factors for blood pressure drop events.

RESULTS

A total of 16,586 instances of intravenous propacetamol administration in 4916 patients were eligible for this study. Intravenous propacetamol resulted in a significant decrease in systolic blood pressure (baseline 131.1 ± 17.8 mm Hg; within 1 h 124.6 ± 17.3 mm Hg; between 1 and 2 h 123.4 ± 17.4 mm Hg; P < 0.01). The incidence of blood pressure drop events was 13.5% within 2 h after intravenous propacetamol. Older age, lower or higher baseline systolic blood pressure, fever, higher Acute Physiology and Chronic Health Evaluation II score, and concomitant administration of vasopressors/inotropes or analgesics/sedatives were significant factors associated with the occurrence of blood pressure drop events after intravenous propacetamol administration.

CONCLUSIONS

Intravenous propacetamol can induce hemodynamic changes and blood pressure drop events in neurocritically ill patients. This study identified the risk factors for blood pressure drop events. On the basis of our results, judicious use of intravenous propacetamol is warranted for neurocritically ill patients with risk factors that make them more susceptible to hemodynamic changes.

The benefit of adding lidocaine to ketamine during rapid sequence endotracheal intubation in patients with septic shock: A randomised controlled trial

BACKGROUND

Patients with septic shock commonly require endotracheal intubation under general anaesthesia in the operating theatre, the emergency department, and the intensive care unit. Hypotension is a serious complication after induction of general anaesthesia, especially in patients with circulatory failure. No randomised controlled trials had previously investigated protocols for induction of anaesthesia in septic shock patients. The aim of the current work is to compare two protocols, lidocaine-ketamine combination versus ketamine full-dose for rapid-sequence endotracheal intubation in patients with septic shock.

METHODS

Forty-four adult patients, with septic shock, scheduled for emergency surgical intervention were enrolled in this randomised, double-blinded, controlled study. Patients were randomised to receive either 1 mg/kg ketamine (ketamine group, n = 22) or 0.5 mg/kg ketamine plus 1 mg/kg lidocaine (ketamine-lidocaine group, n = 22) for induction of anaesthesia in addition to 0.05 mg/kg midazolam (in both groups). Our primary outcome was the mean arterial pressure (MAP). Other outcomes included frequency of post-induction hypotension, heart rate, and cardiac output.

RESULTS

Forty-three patients were available for final analysis. The average MAP reading in the first 5 min post-induction was higher in ketamine-lidocaine group than in the ketamine group {82.8 ± 5.6 mmHg and 73 ± 10.2 mmHg, P < 0.001}. Furthermore, the incidence of post-intubation hypotension was lower in the ketamine-lidocaine group than in the ketamine group {1 patient (5%) versus 17 patients (77%), P < 0.001}. The ketamine-lidocaine group showed higher MAP in almost all the readings after induction compared to ketamine group. Other haemodynamic variables including cardiac output and heart rate were comparable between both study groups.

CONCLUSION

Lidocaine-ketamine combination showed less incidence of hypotension compared to ketamine full-dose when used for rapid-sequence endotracheal intubation in patients with septic shock. REGISTRATION URL: https://clinicaltrials.gov/ct2/show/NCT03844984?cond=NCT03844984&rank=1.

Overview of Management of Intermediate- and High-Risk Pulmonary Embolism

Anticoagulation is the cornerstone of acute pulmonary embolism (PE) therapy. Intermediate-risk (submassive) or high-risk (massive) PE patients have higher mortality than low-risk patients. It is generally accepted that high-risk PE patients should be considered for more aggressive therapy. Intermediate-risk patients can be subdivided, although more than simply categorizing the patient is required to guide therapy. Therapeutic approaches depend on a prompt, detailed evaluation, and PE response teams may help with rapid assessment and initiation of therapy. More clinical trial data are needed to guide clinicians in the management of acute intermediate- and high-risk PE patients.

The Use of Ketamine for Air Medical Rapid Sequence Intubation Was Not Associated With a Decrease in Hypotension or Cardiopulmonary Arrest

OBJECTIVE

Rapid sequence intubation (RSI) is associated with a number of complications that can increase morbidity and mortality. Among RSI agents used to blunt awareness of the procedure and produce amnesia, ketamine is unique in its classification as a dissociative agent rather than a central nervous system depressant. Thus, ketamine should have a lower risk of peri-RSI hypotension because of the minimal sympatholysis compared with other agents. Recent recommendations include the use of ketamine for RSI in hemodynamically unstable patients. The main goal of this analysis was to explore the incidence of hypotension and/or cardiopulmonary arrest in patients receiving ketamine, etomidate, midazolam, and fentanyl during air medical RSI. We hypothesized that ketamine would be associated with a lower risk of hemodynamic complications, particularly after adjusting for covariables reflecting patient acuity. In addition, we anticipated that an increased prevalence of ketamine use would be associated with a decreased incidence of peri-RSI hypotension and/or arrest.

METHODS

This was a retrospective, observational study using a large air medical airway database. A waiver of informed consent was granted by our institutional review board. Descriptive statistics were used to present demographic and clinical data. The incidence rates of hypotension and cardiopulmonary arrest were calculated for each sedative/dissociative agent. Multivariable logistic regression was used to calculate the odds ratios of both hypotension and arrest for each of the sedative/dissociative agents. The prevalence of use for each agent and the incidence of hemodynamic complications (hypotension and arrest) were determined over time.

RESULTS

A total of 7,466 RSI patients were included in this analysis. The use of ketamine increased over the duration of the study. Ketamine was associated with a higher incidence of both hypotension and arrest compared with other agents, even after adjustment for multiple covariables. The overall incidence of hypotension, desaturation, and cardiopulmonary arrest did not change over the study period.

CONCLUSIONS

Although the incidence of hemodynamic complications was higher in patients receiving ketamine, this may reflect a selection bias toward more hemodynamically unstable patients in the ketamine cohort. The incidence of hypotension and arrest did not change over time despite an increase in the prevalence of ketamine use for air medical RSI. These data do not support a safer hemodynamic profile for ketamine.

Comparison of the Sedation Quality of Etomidate, Propofol, and Midazolam in Combination with Fentanyl During Phacoemulsification Cataract Surgery: A Double-Blind, Randomized, Controlled, Clinical Trial

Background

According to the favorable effects of combination therapy to provide better sedation during phacoemulsification and lack of any studies investigating the sedative effect of etomidate, propofol, and midazolam in combination with fentanyl during the procedure.

Objectives

The current study aimed at comparing the sedative properties of the mentioned three combination therapies in this field.

Methods

The current double-blind, randomized, controlled clinical trial was conducted on patients referred for elective phacoemulsification surgery under sedation. They were randomly allocated to the three groups to receive fentanyl plus one of the following medications: Propofol, midazolam, and etomidate. Demographic characteristics, medical condition, and hemodynamic parameters before, during, and after surgery, sedation level, anesthetic complications, sedation-related adverse events, and patients' and surgeons' satisfaction were evaluated and recorded by the anesthesiologist and compared in the three studied groups.

Results

In the current study, out of 150 enrolled patients, 98 completed the study. Frequency of different levels of Ramsay scores was not significantly different between the groups (P = 0.41). Frequency of Ramsay scores 3 and 4 was 92%, 79.4%, and 88.2% in etomidate, midazolam and propofol groups, respectively (P = 0.32). The median recovery time was significantly higher in the midazolam group than the propofol group (P = 0.04); intergroup comparisons indicated that the patients' mean score of satisfaction in the propofol group was significantly higher than that of the etomidate group (P = 0.006).

Conclusions

The current study findings indicated that though the quality of sedation during phacoemulsification cataract surgery was acceptable in the three agents and the results had no significantly differences among the groups, and considering other factors including recovery time, hemodynamic evaluation, sedation-related complications, and patients' satisfication scores, it is suggested that propofol was superior to the other two agents.

Collective Review of the Status of Rapid Sequence Intubation Drugs of Choice in Trauma in Low- and Middle-Income Settings (Prehospital, Emergency Department and Operating Room Setting)

INTRODUCTION

Establishing a definitive airway in order to ensure adequate ventilation and oxygenation is an important aspect of resuscitation of the polytrauma patient .

AIM

To review the relevant literature that compares the different drugs used for rapid sequence intubation (RSI) of trauma patients, specifically reviewing: premedication, induction agents and neuromuscular blocking agents across the prehospital, emergency department and operating room setting, and to present the best practices based on the reviewed evidence.

METHOD

A literature review of rapid sequence intubation in the trauma population was carried out, specifically comparison of the drugs used (induction agent, neuromuscular blocking drugs and adjuncts).

DISCUSSION

Studies involving the comparison of drugs used in RSI in, specifically, the trauma patient are sparse. The majority of studies have compared induction agents, etomidate, ketamine and propofol, as well as the neuromuscular blocking agents, succinylcholine and rocuronium.

CONCLUSION

There currently exists great variation in the practice of RSI; however, in trauma the RSI armamentarium is limited to agents that maintain hemodynamic stability, provide adequate intubating conditions in the shortest time period and do not have detrimental effects on cerebral perfusion pressure. Further, multicenter randomized controlled studies to confirm the benefits of the currently used agents in trauma are required.

A comparison of emergency airway management between neuromuscular blockades alone and rapid sequence intubation: an analysis of multicenter prospective study

Background

Although airway management with neuromuscular blockade (NMB) alone is discouraged in the emergency department (ED), our previous study demonstrated that many patients were intubated using NMBs alone without sedatives. To refute this practice, we sought to compare the intubation success and adverse event rates between NMBs only and rapid sequence intubation (RSI).

Methods

This is a secondary analysis of the data from a prospective observational study of ED patients in 13 hospitals who underwent emergency airway management from April 2010 to August 2012. The primary outcome was intubation success rate on first attempt. The secondary outcomes were the intubation success rate in ≤2 attempts and the intubation-related adverse event rate. We compared these outcomes between intubation attempts using NMB alone and RSI. We fit multivariable logistic regression models adjusting for potential confounders (age, sex, weight, primary indication for intubation, and training level of intubators).

Results

Overall, 852 patients were eligible for this analysis, with 114 (13%) intubated with NMB alone and 738 (87%) with RSI. Between the NMB-alone and RSI groups, no significant differences were observed in the success rate on the first attempt (70 vs. 73%; P = 0.48) or in ≤2 attempts (89 vs. 91%; P = 0.46), or in the adverse event rate (11 vs. 12%; P = 0.58). Similarly, after adjusting for confounders, no significant differences were observed in any of these outcomes (all P > 0.05).

Conclusions

In this analysis of data from a large multicenter study of ED patients, we found no superior effectiveness of intubation with NMB alone when compared to RSI. Our data lend significant support to the concept that intubation with NMB alone should be avoided in the ED.

Postintubation Hypotension in General Anesthesia: A Retrospective Analysis

BACKGROUND

Postintubation hypotension (PIH) is an adverse event associated with poor outcomes in emergency department endotracheal intubations. Study objective was to determine the incidence of PIH and its impact on outcomes following tracheal intubation in a general anesthesia population.

METHODS

Structured chart audit of adult patients intubated for a vascular surgery procedure at a tertiary care center over a 3-year period. Outcomes included in-hospital mortality, extended intensive care unit length of stay (ICU LOS), and requirement for postoperative (postop) hemodialysis or mechanical ventilation.

RESULTS

Incidence of PIH was 60% (837 of 1395). Patients who developed PIH had increased mortality (8.8% PIH vs 5.2% no-PIH; P = .014), extended ICU LOS (7.9% PIH vs 2.0% no-PIH; P < .001), and postop mechanical ventilation requirement (20.7% PIH vs 3.8% no-PIH; P < .001). When controlling for confounding factors, PIH was associated with extended ICU LOS (odds ratio [OR] 2.55, 95% confidence interval [CI] 1.01-6.62, P = .049), postop ventilation (OR 2.43, 95% CI 1.27-4.74, P = .008), and a composite end point (OR 1.72, 95% CI 1.02-2.92, P = .043).

CONCLUSIONS

Development of PIH occurs in 60% of patients undergoing intubation for vascular surgery and was associated with adverse outcomes including extended ICU LOS and postop ventilation requirement.

Incidence of postintubation hemodynamic instability associated with emergent intubations performed outside the operating room: a systematic review

OBJECTIVE

Hemodynamic instability following emergent endotracheal intubation (EETI) is a potentially life-threatening adverse event. The objectives of this systematic literature review were to document the incidence of postintubation hemodynamic instability (PIHI), to determine the definitions for PIHI used in the available literature, and to examine factors associated with PIHI in adult patients who require EETI.

DATA SOURCE

Articles published in Medline (1966-August 2012).

STUDY SELECTION

This systematic review included adult, in-hospital studies of EETIs. Studies with nonemergent or pediatric patient populations were excluded.

DATA EXTRACTION

Two authors independently performed data abstraction. Disagreements were resolved by a third party. The methodological quality of included studies was assessed with the Newcastle-Ottawa Quality Assessment Scale for Cohort Studies.

DATA SYNTHESIS

We estimated the pooled prevalence of PIHI across studies using a random effects meta-analysis. Subgroups analyzed included study design, intubation setting, geographic location of the study, physician experience, medications used for sedation, neuromuscular blockade, and definition of PIHI. Eighteen studies were analyzed, with sample sizes from 84 to 2,833 patients. The incidence of PIHI ranged from 5 to 440 cases per 1,000 intubations, with a pooled estimate of 110 cases per 1,000 intubations (95% CI 65-167).

CONCLUSIONS

PIHI was found to occur in 110 cases per 1,000 in-hospital, emergent intubations. However, heterogeneity among the included studies limits the reliability of this summary estimate. Further investigation is warranted.

Prospective observational study of emergent endotracheal intubation practice in the intensive care unit and emergency department of an Australian regional tertiary hospital

OBJECTIVE

The present study aimed to describe the characteristics and outcomes of intubation occurring in the ICU and ED of an Australian tertiary teaching hospital.

METHODS

This was a prospective observational study of intubation practice across the Geelong Hospital over a 6 month period from 1 August 2012 to 31 January 2013. Data were entered by the intubating team through an online data collection form.

RESULTS

There were 119 patients intubated and 134 attempts at intubation in the ED and ICU over a 6 month period. The first-pass success rate was 104/119 (87.4%), and all but a single patient was intubated by the second attempt. Propofol, fentanyl, midazolam and suxamethonium were the most common drugs used in rapid sequence induction. AEs were reported in 44/134 (32.8%) of intubation attempts, with transient hypoxia and hypotension being the most common. A significant adverse outcome, namely aspiration pneumonitis, occurred in one patient. There were no peri-intubation deaths.

CONCLUSION

The majority of airways are managed by ICU and ED consultants and trainees, with success rates and AE rates comparable with other published studies.

Long-acting neuromuscular blocker use during prehospital transport of trauma patients

INTRODUCTION

The purpose of this study was to determine the rate of long-acting neuromuscular blocker (LA-NMB) use and evaluate the concurrent use of sedatives during prehospital care.

SETTING

Prehospital patients who were brought to a single emergency department in the United States.

METHODS

This was a retrospective cohort study of trauma patients who were intubated in the prehospital setting. The primary outcome measure was to determine the rate of LA-NMB use. The use of postintubation sedatives and the time to the administration of sedative agents was compared between patients who received an LA-NMB and those who did not.

RESULTS

A total of 51 patients were included in the final analyses. Overall, 82% (n = 42) of patients received an LA-NMB during transport. There was no difference in the rate of postintubation sedative use during transport between the LA-NMB and no LA-NMB groups (79% vs. 67%, respectively, P = .42). The LA-NMB group received sedatives less promptly after intubation compared with those who did not receive LA-NMBs (16 vs. 7 minutes, respectively; P = .04).

CONCLUSION

The use of LA-NMB is common during the prehospital transport of trauma patients. Some of these patients may not be given sedatives or may have delays in receiving sedatives after intubation.

Increased incidence of hypotension in elderly patients who underwent emergency airway management: an analysis of a multi-centre prospective observational study

Background

Although the number of elderly increases disproportionately throughout the industrialised nations and intubation-related cardiovascular compromise is associated with hospital mortality, no emergency medicine literature has reported the direction and magnitude of effect of advanced age on post-intubation hypotension. We seek to determine whether advanced age is associated with an increased rate of hypotension at airway management in emergency departments (EDs).

Methods

We conducted an analysis of a multi-centre prospective observational study of 13 Japanese EDs from April 2010 to March 2012. Inclusion criteria were all adult non-cardiac-arrest patients who underwent emergency intubation. We excluded patients in whom airway management was performed for shock or status asthmaticus as the principal indication. Patients were divided into two groups defined a priori: age ≥ 65 years old (elderly group) and age < 65 years old (younger group). The primary outcome measure was post-intubation hypotension in the ED.

Results

During the 24-month period, 4,043 subjects required emergency airway management at 13 EDs. Among these, the database recorded 3,872 intubations (capture rate 96%). Of 1,903 eligible patients, 975 patients were age ≥ 65 years (51%) and 928 patients were age < 65 years (49%). The elderly group had a significantly higher rate of post-intubation hypotension compared with the younger group [3% vs. 1%; unadjusted OR 2.7 (95% CI, 1.3–5.6); P = 0.005]. In a model controlling for potential confounders (sex, principal indication, method, medication used to intubate, multiple intubation attempts), advanced age had an adjusted OR for post-intubation hypotension of 2.6 (95% CI, 1.3–5.6; P = 0.01).

Conclusions

In this large multi-centre study of ED patients who underwent emergent airway management, we found that elderly patients have a significantly higher risk of post-intubation hypotension. These data provide implications for the education and practice of ED airway management that may lead to better clinical outcomes and improved patient safety.

Anesthetic drug development: Novel drugs and new approaches

The ideal sedative–hypnotic drug would be a rapidly titratable intravenous agent with a high therapeutic index and minimal side effects. The current efforts to develop such agents are primarily focused on modifying the structures of existing drugs to improve their pharmacodynamic and pharmacokinetic properties. Drugs currently under development using this rational design approach include analogues of midazolam, propofol, and etomidate, such as remimazolam, PF0713, and cyclopropyl methoxycarbonyl-etomidate (MOC-etomidate), respectively. An alternative approach involves the rapid screening of large libraries of molecules for activity in structural or phenotypic assays that approximate anesthetic and target receptor interactions. Such high-throughput screening offers the potential for identifying completely novel classes of drugs. Anesthetic drug development is experiencing a resurgence of interest because there are new demands on our clinical practice that can be met, at least in part, with better agents. The goal of this review is to provide the reader with a glimpse of the novel anesthetic drugs and new developmental approaches that lie on the horizon.

Evaluation of the incidence, risk factors, and impact on patient outcomes of postintubation hemodynamic instability

OBJECTIVES

Postintubation hemodynamic instability (PIHI) is a potentially life-threatening adverse event of emergent endotracheal intubation. The objectives of this study were to determine the incidence, risk factors, and impact on patient outcomes associated with PIHI in intubations performed in emergency medicine.

METHODS

A structured chart audit was performed of all consecutive adult patients requiring emergent endotracheal intubations over a 16-month period at a tertiary care emergency department (ED). Data collection included medications, comorbidities, vital signs in the 30 minutes before and after intubation, hospital length of stay, and in-hospital mortality. PIHI was defined as a decrease in systolic blood pressure (SBP) to ≤ 90 mm Hg, a decrease in SBP of ≥ 20% from baseline, a decrease in mean arterial pressure to ≤ 65 mm Hg, or the initiation of any vasopressor medication at any time in the 30 minutes following intubation.

RESULTS

Overall, 218 patients intubated in the ED were identified, and 44% (96 of 218) developed PIHI. On multivariate analysis, increasing age (OR 1.03, 95% CI 1.01-1.05), chronic obstructive pulmonary disease (OR 3.00, CI 1.19-7.57), and pre-emergent endotracheal intubation hemodynamic instability (OR 2.52, 95% CI 1.27-4.99) were associated with the development of PIHI. The use of a neuromuscular blocking medication was associated with a decreased incidence of PIHI (OR 0.34, 95% CI 0.16-0.75).

CONCLUSIONS

Based on our data, postintubation hypotension occurs in a significant proportion of ED patients requiring emergent airway control. Further investigation is needed to confirm the factors we found to be associated with PIHI and to determine if PIHI is associated with increased morbidity and mortality.

Neuromuscular blocking agent administration for emergent tracheal intubation is associated with decreased prevalence of procedure-related complications

BACKGROUND

Emergent intubation is associated with a high rate of complications. Neuromuscular blocking agents are routinely used in the operating room and emergency department to facilitate intubation. However, use of neuromuscular blocking agents during emergent airway management outside of the operating room and emergency department is controversial. We hypothesized that the use of neuromuscular blocking agents is associated with a decreased prevalence of hypoxemia and reduced rate of procedure-related complications.

METHODS

Five hundred sixty-six patients undergoing emergent intubations in two tertiary care centers, Massachusetts General Hospital, Boston, MA, and the University of California Los Angeles, Ronald Reagan Medical Center, Los Angeles, CA, were enrolled in a prospective, observational study. The 112 patients intubated during cardiopulmonary resuscitation were excluded, leaving 454 patients for analysis. All intubations were supervised by attendings trained in Critical Care Medicine. We measured intubating conditions, oxygen saturation during and 5 mins following intubation. We assessed the prevalence of procedure-related complications defined as esophageal intubation, traumatic intubation, aspiration, dental injury, and endobronchial intubation.

RESULTS

The use of neuromuscular blocking agents was associated with a lower prevalence of hypoxemia (10.1% vs. 17.4%, p = .022) and a lower prevalence of procedure-related complications (3.1% vs. 8.3%, p = .012). This association persisted in a multivariate analysis, which controlled for airway grade, sedation, and institution. Use of neuromuscular blocking agents was associated with significantly improved intubating conditions (laryngeal view, p = .014; number of intubation attempts, p = .049). After controlling for the number of intubation attempts and laryngoscopic view, muscle relaxant use is an independent predictor of complications associated with emergency intubation (p = .037), and there is a trend towards improvement of oxygenation (p = .07).

CONCLUSION

The use of neuromuscular blocking agents, when used by intensivists with a high level of training and experience, is associated with a decrease in procedure-related complications.

Predictors of the complication of postintubation hypotension during emergency airway management

OBJECTIVE

Arterial hypotension is a recognized complication of emergency intubation that is independently associated with increased morbidity and mortality. Our aim was to identify factors associated with postintubation hypotension after emergency intubation.

METHODS

Retrospective cohort study of tracheal intubations performed in a large, urban emergency department over a 1-year period. Patients were included if they were older than 17 years and had no systolic blood pressure measurements below 90 mm Hg for 30 consecutive minutes before intubation. Patients were analyzed in 2 groups, those with postintubation hypotension (PIH), defined as any recorded systolic blood pressure less than 90 mm Hg within 60 minutes of intubation, and those with no PIH. Multiple logistic regression modeling was used to define predictors of PIH.

RESULTS

A total 465 patients underwent emergency intubation during the study period, and 300 met inclusion criteria for this study. Postintubation hypotension occurred in 66 (22%) of 300 patients, and these patients experienced significantly higher in-hospital mortality (35% vs 20%; odds ratio [OR] 2.1; 95% confidence interval [CI], 1.2-3.9). Multiple logistic regression analysis demonstrated that preintubation shock index (SI), chronic renal disease, intubation for acute respiratory failure, and age were independently associated with PIH. Of these, SI was the most strongly associated factor (OR, 55; 95% CI, 13-232). Receiver operating characteristic plot showed optimized SI 0.8 or higher predicting PIH with 67% sensitivity and 80% specificity. Rapid sequence intubation paralysis was associated with a lower incidence of PIH (OR, 0.04; 95% CI, 0.003-0.4).

CONCLUSIONS

Preintubation and peri-intubation factors predict the complication of PIH. Elevated SI strongly and independently forewarned of cardiovascular deterioration after emergency intubation with pre-RSI SI 0.8 or higher as the optimal threshold to identify patients at risk.

Differential effects of etomidate and its pyrrole analogue carboetomidate on the adrenocortical and cytokine responses to endotoxemia

OBJECTIVE

We developed a novel pyrrole analog of etomidate, (R)-ethyl 1-(1-phenylethyl)-1H-pyrrole-2-carboxylate (carboetomidate), which retains etomidate's desirable anesthetic and hemodynamic properties but lacks its potent inhibitory affect on adrenocorticotropic hormone-stimulated steroid synthesis. The objective of this study was to test the hypothesis that in contrast to etomidate, carboetomidate neither suppresses the adrenocortical response to endotoxemia nor enhances the accompanying production of proinflammatory cytokines.

DESIGN

Animal study.

SETTING

University research laboratory.

SUBJECTS

Male Sprague-Dawley rats.

INTERVENTIONS

For both single and multiple anesthetic dose studies, rats were injected with Escherichia coli lipopolysaccharide immediately followed by a hypnotic dose of etomidate, carboetomidate, or vehicle alone (dimethyl sulfoxide) as a control. For single-dose studies, no additional anesthetic (or vehicle) was administered. For multiple anesthetic dose studies, additional doses of anesthetic (or vehicle) were administered every 15 mins for a total of eight anesthetic (or vehicle) doses.

MEASUREMENTS AND MAIN RESULTS

Plasma adrenocorticotropic hormone, corticosterone, and cytokine concentrations were measured before lipopolysaccharide administration and intermittently throughout the 5-hr experiment. In single anesthetic dose studies, plasma adrenocorticotropic hormone and cytokine concentrations were not different at any time point among the etomidate, carboetomidate, and vehicle groups, whereas plasma corticosterone concentrations were briefly (60-120 mins) reduced in the etomidate group. In multiple anesthetic dose studies, plasma corticosterone concentrations were persistently lower and peak plasma interleukin-1β and interleukin-6 concentrations were higher in the etomidate group vs. the carboetomidate and control groups. Peak plasma interleukin-10 concentrations were similarly elevated in the etomidate and carboetomidate groups vs. the control group.

CONCLUSIONS

Compared with etomidate, carboetomidate produces less suppression of adrenocortical function and smaller increases in proinflammatory cytokine production in an endotoxemia model of sepsis. These findings suggest that carboetomidate could be a useful alternative to etomidate for maintaining anesthesia for a prolonged period of time in patients with sepsis.

The role of the emergency pharmacist in trauma resuscitation

The clinical pharmacist in the emergency department is now commonly incorporated as a member of the emergency department trauma team. As such, the emergency pharmacist needs to have detailed knowledge of the pharmacotherapy of resuscitation and be able to apply the skills needed to function as a valuable member of this team. In addition to the traditional skills of the discipline of clinical pharmacy, the emergency pharmacist must be familiar with the intricacies of treating life-threatening injuries in an emergent setting and be able to anticipate the direction of the patient's care. The ability to provide valuable pharmacological interventions throughout the resuscitation and stabilization process requires familiarity with the process of resuscitation, including rapid sequence induction, analgesia and sedation, seizure prophylaxis, appropriate antibiotic and tetanus prophylaxis, intracranial pressure control, hemodynamic stabilization, and any other specific drug therapy that the clinical situation demands. This article discusses the aforementioned pharmacotherapeutic topics and describes the role of the Emergency Pharmacist on the ED trauma team.

Etomidate as an induction agent in septic patients: red flags or false alarms?

Despite its widespread use in North America and many other parts of the world, the safety of etomidate as an induction agent for rapid sequence intubation in septic patients is still debated. In this article, we evaluate the current literature on etomidate, review its clinical history, and discuss the controversy regarding its use, especially in sepsis. We address eight questions: (i) When did concern over the safety of etomidate first arise? (ii) What is the mechanism by which etomidate is thought to affect the adrenal axis? (iii) How has adrenal insufficiency in relation to etomidate use been defined or identified in the literature? (iv) What is the evidence that single dose etomidate is associated with subsequent adrenal-cortisol dysfunction? (v) What is the clinical significance of adrenal insufficiency or dysfunction associated with single dose etomidate, and where are the data that support or refute the contention that single-dose etomidate is associated with increased mortality or important post emergency department (ED) clinical outcomes? (vi) How should etomidate's effects in septic patients best be measured? (vii) What are alternative induction agents and what are the advantages and disadvantages of these agents relative to etomidate? (viii) What future work is needed to further clarify the characteristics of etomidate as it is currently used in patients with sepsis? We conclude that the observational nature of almost all available data suggesting adverse outcomes from etomidate does not support abandoning its use for rapid sequence induction. However, because we see a need to balance theoretical harms and benefits in the presence of data supporting the non-inferiority of alternative agents without similar theoretical risks associated with them, we suggest that the burden of proof to support continued widespread use may rest with the proponents of etomidate. We further suggest that practitioners become familiar with the use of more than one agent while awaiting further definitive data.

Newer agents for rapid sequence intubation: etomidate and rocuronium

The emergency airway management of children and adolescents with critical illnesses may necessitate rapid sequence intubation with a sedating and a neuromuscular blocking agent. Etomidate and rocuronium have become increasingly popular for the sedation and paralysis, respectively, of pediatric patients in rapid sequence intubation, and there are many advantages to the use of both agents. Both etomidate and rocuronium have a rapid onset of action, and both agents are relatively free of hemodynamic adverse effects. Etomidate does, however, suppress adrenal function, and consequently, its use in patients with septic shock is controversial. Rocuronium can produce optimal intubating conditions without the serious complications that can accompany succinylcholine. The available evidence supports the safety of etomidate and rocuronium in rapid sequence intubation but also suggests that more prospective studies are needed in pediatric patients.

Etomidate should be used carefully for emergent endotracheal intubation in patients with septic shock

Etomidate and midazolam are the most popular drugs among the induction agents for emergent endotracheal intubation. The purpose of this study was to compare the incidence of adrenal insufficiency and mortality between the septic shock patients who received etomidate (ETM group) and those who received midazolam (MDZ group). Between November 2004 and September 2006, 65 patients were analyzed in this study. The hospital mortality rate was 36% in the ETM group (n=25) and 50% in the MDZ group (n=40), which was not statistically significant (p=0.269). The incidence of relative adrenal insufficiency was significantly higher in the ETM group than in the MDZ group (84% and 48%, respectively; p=0.003). On multivariate analysis, the use of etomidate was the only significant factor affecting the incidence of relative adrenal insufficiency (odds radio, 5.59; 95% confidence interval, 1.61-19.4). In conclusion, we think that physicians who treat patients with septic shock should be aware that etomidate can cause adrenal insufficiency, and should start corticosteroids if etomidate is administered.

A dose escalation study in sheep of the effects of the benzodiazepine CNS 7056 on sedation, the EEG and the respiratory and cardiovascular systems

BACKGROUND AND PURPOSE

CNS 7056 is a new, rapidly metabolized benzodiazepine. The effects of escalating doses of CNS 7056 on sedation, and respiratory and cardiovascular function, were examined in conscious, chronically instrumented sheep for the first time.

EXPERIMENTAL APPROACH

Three sheep were given doses of CNS 7056 (0, 0.037, 0.074, 0.18, 0.37, 0.74, 2.21, 4.41 and 8.82 mg kg(-1)) as 2 min intravenous infusions in order on consecutive days. A range of physiological variables, including the EEG, were measured.

KEY RESULTS

Sheep became transiently drowsy for the lowest (0.037 and 0.074 mg kg(-1)) doses of CNS 7056, whereas the highest (8.82 mg kg(-1)) dose produced profound loss of consciousness (LOC) for over 30 min. The EEG alpha power correlated well (r=0.91) with duration of LOC and had a high signal-to-noise ratio. CNS 7056 reduced respiratory rate (maximum 33%) and dose-dependently increased arterial carbon dioxide tension (maximum 12%). There was a transient, dose-related reduction in arterial oxygen tension (maximum 34%), but haemoglobin desaturation was minimal (maximum 4%). CNS 7056 produced a dose-related transient drop in mean arterial blood pressure (maximum 12%) but cardiac output was unchanged.

CONCLUSIONS AND IMPLICATIONS

Doses of 0.37-2.21 mg kg(-1) of CNS 7056 produced sedation for 9-25 min without excessive respiratory or cardiovascular depression, and would be suitable for pharmacokinetic studies. The power in the alpha band of the EEG can be used as a continuous measure of the sedative effects of CNS 7056.

Should etomidate be used for rapid-sequence intubation induction in critically ill septic patients?

Etomidate is an agent often used by emergency medicine physicians for rapid-sequence intubation induction of critically ill patients because of its reliable pharmacokinetics and cardiovascular stability. Etomidate is known to inhibit endogenous cortisol production through inhibition of 11beta-hydroxylase. Previous studies in undifferentiated emergency department patients and healthy, elective surgical patients have shown this effect to be only transient and not clinically significant. Recent retrospective studies in the pediatric and adult intensive care literature have shown an association between a single induction dose of etomidate in critically ill septic patients and sustained suppression of the adrenal axis with an increase in mortality. It is unknown at this time if any increase in mortality associated with etomidate-induced adrenal suppression would be offset by concomitant corticosteroid administration. Aggressive resuscitation of septic patients with fluids, antibiotics, and vasopressors has been shown to significantly reduce mortality and may allow for the use of alternative agents that had previously been discouraged because of concern for hemodynamic collapse during intubation. A prospective randomized trial in septic patients of etomidate induction with early corticotropin stimulation testing or corticosteroid supplementation vs the use of alternative induction agents with enough power to detect differences in mortality is needed to further address this clinical dilemma.

Complications of emergency tracheal intubation: hemodynamic alterations--part I

Emergency airway management outside the elective operating room presents considerable risks to the patient and significant challenges to the practitioner. Complications and adverse consequences are commonplace, yet they have not received their justified discussion or scrutiny in the literature. This review will discuss potentially life-threatening complications partitioned into 2 broad categories: hemodynamic and airway. Part 1 will focus on alterations in the heart rate and blood pressure, new onset cardiac dysrhythmias and cardiac arrest. Part 2 will explore airway related consequences such as hypoxemia, esophageal intubation, multiple intubation attempts, and aspiration.

Etomidate Versus Midazolam for Out-of-Hospital Intubation: A Prospective, Randomized Trial

STUDY OBJECTIVE

The primary objective of this study is to compare the intubation success rates of etomidate and midazolam when used for sedative-facilitated intubation, without paralytics, in out-of-hospital adult patients.

METHODS

This prospective, double-blind, randomized trial was conducted with 2 ground out-of-hospital advanced life support systems (ALS); all patients aged 18 or older who required out-of-hospital sedative-facilitated intubation were eligible for participation. The ambulances were stocked with blinded numbered syringes containing either 7 mg of midazolam or 20 mg of etomidate. No paralytics were used. If sedation was not achieved with the study drug, medics could request additional sedation from a medical command physician; only midazolam or diazepam were available outside of the study.

RESULTS

One hundred ten patients were enrolled in the study; 55 patients received midazolam and 55 patients received etomidate. The 2 groups were similar with regard to age, sex, initial vital signs, and reasons for intubation or sedation. The overall intubation success rate was 76% (95% confidence interval [CI] 68% to 84%); 75% (41/55) for midazolam (95% CI 64% to 86%) and 76% (42/55) for etomidate (95% CI 65% to 87%). There was also no difference in incidence of hypotension, number of intubation attempts, or perceived difficulty of intubation. Additional sedation was requested almost equally for the 2 groups: 14 patients in the midazolam group and 12 patients in the etomidate group. A benzodiazepine was successful for rescue of a failed etomidate intubation 10 of 12 times (83%; 95% CI 62% to 100%). When used for rescue of failed midazolam intubations, benzodiazepines were effective in only 5 of 14 (36%, 95% CI 11% to 61%) attempts.

CONCLUSION

There were no observed differences between midazolam and etomidate in sedation-facilitated intubation success rates; we could not fully evaluate global outcomes of these agents or the sedative-facilitated intubation strategy itself.