Cardiac arrest following ketamine administration for rapid sequence intubation

Rapid Sequence Intubation, is it Time to Find an Alternative Induction Agent? A Narrative Review

Objective: To review the efficacy, safety, and place in therapy of fentanyl as an induction agent for rapid sequence intubation (RSI) in critically ill patients. Data Sources: A comprehensive search of PubMed, EMBASE, and clinical trial registries (1964-June 2021) was performed utilizing the keywords fentanyl, rapid sequence intubation, intubation, induction, anesthesia, hemodynamics, operating room (OR), and emergency. Study Selection and Data Extraction: Only primary literature evaluating fentanyl in combination with a sedative or as the sole induction agent was included in the final analysis. Primary literature included peer-reviewed publications and results posted on ClinicalTrials.gov actively recruiting participants. Data Synthesis: Fentanyl has been used for decades as an adjunct, and sole induction agent in the OR. Questions surrounding the use of fentanyl as a sole induction agent include optimal dosing and safety in critically ill patients as evaluation in non-OR settings remain limited. Relevance to Patient Care and Clinical Practice: Commonly used induction agents (eg, etomidate and ketamine) are associated with adverse events that may increase risk of morbidity and mortality. Fentanyl, a high-potency opioid could serve as an alternative induction agent for RSI due to its neutral hemodynamic response and fast onset of action. This paper compiles and describes existing data on the use of fentanyl as an induction agent for RSI. Conclusion: Fentanyl in combination with sedatives provides optimal intubating conditions with minimal impact on hemodynamic parameters. Future studies should focus on safety and impact of awareness during paralysis before fentanyl can be considered as a sole induction agent.

Etomidate versus Ketamine as Prehospital Induction Agent in Patients with Suspected Severe Traumatic Brain Injury

BACKGROUND

Severe traumatic brain injury is a leading cause of morbidity and mortality among young people around the world. Prehospital care focuses on the prevention and treatment of secondary brain injury and commonly includes tracheal intubation after induction of general anesthesia. The choice of induction agent in this setting is controversial. This study therefore investigated the association between the chosen induction medication etomidate versus S(+)-ketamine and the 30-day mortality in patients with severe traumatic brain injury who received prehospital airway management in the Netherlands.

METHODS

This study is a retrospective analysis of the prospectively collected observational data of the Brain Injury: Prehospital Registry of Outcomes, Treatments and Epidemiology of Cerebral Trauma (BRAIN-PROTECT) cohort study. Patients with suspected severe traumatic brain injury who were transported to a participating trauma center and who received etomidate or S(+)-ketamine for prehospital induction of anesthesia for advanced airway management were included. Statistical analyses were performed with multivariable logistic regression and inverse probability of treatment weighting analysis.

RESULTS

In total, 1,457 patients were eligible for analysis. No significant association between the administered induction medication and 30-day mortality was observed in unadjusted analyses (32.9% mortality for etomidate versus 33.8% mortality for S(+)-ketamine; P = 0.716; odds ratio, 1.04; 95% CI, 0.83 to 1.32; P = 0.711), as well as after adjustment for potential confounders (odds ratio, 1.08; 95% CI, 0.67 to 1.73; P = 0.765; and risk difference 0.017; 95% CI, -0.051 to 0.084; P = 0.686). Likewise, in planned subgroup analyses for patients with confirmed traumatic brain injury and patients with isolated traumatic brain injury, no significant differences were found. Consistent results were found after multiple imputations of missing data.

CONCLUSIONS

The analysis found no evidence for an association between the use of etomidate or S(+)-ketamine as an anesthetic agent for intubation in patients with traumatic brain injury and mortality after 30 days in the prehospital setting, suggesting that the choice of induction agent may not influence the patient mortality rate in this population.

EDITOR’S PERSPECTIVE

Ketamine versus etomidate for rapid sequence intubation in patients with trauma: a retrospective study in a level 1 trauma center in Korea

BACKGROUND

Ketamine and etomidate are commonly used as sedatives in rapid sequence intubation (RSI). However, there is no consensus on which agent should be favored when treating patients with trauma. This study aimed to compare the effects of ketamine and etomidate on first-pass success and outcomes of patients with trauma after RSI-facilitated emergency intubation.

METHODS

We retrospectively reviewed 944 patients who underwent endotracheal intubation in a trauma bay at a Korean level 1 trauma center between January 2019 and December 2021. Outcomes were compared between the ketamine and etomidate groups after propensity score matching to balance the overall distribution between the two groups.

RESULTS

In total, 620 patients were included in the analysis, of which 118 (19.9%) were administered ketamine and the remaining 502 (80.1%) were treated with etomidate. Patients in the ketamine group showed a significantly faster initial heart rate (105.0 ± 25.7 vs. 97.7 ± 23.6, p = 0.003), were more hypotensive (114.2 ± 32.8 mmHg vs. 139.3 ± 34.4 mmHg, p < 0.001), and had higher Glasgow Coma Scale (9.1 ± 4.0 vs. 8.2 ± 4.0, p = 0.031) and Injury Severity Score (32.5 ± 16.3 vs. 27.0 ± 13.3, p < 0.001) than those in the etomidate group. There were no significant differences in the first-pass success rate (90.7% vs. 90.1%, p > 0.999), final mortality (16.1% vs. 20.6, p = 0.348), length of stay in the intensive care unit (days) (8 [4, 15] (Interquartile range)), vs. 10 [4, 21], p = 0.998), ventilator days (4 [2, 10] vs. 5 [2, 13], p = 0.735), and hospital stay (days) (24.5 [10.25, 38.5] vs. 22 [8, 40], p = 0.322) in the 1:3 propensity score matching analysis.

CONCLUSION

In this retrospective study of trauma resuscitation, those receiving intubation with ketamine had greater hemodynamic instability than those receiving etomidate. However, there was no significant difference in clinical outcomes between patients sedated with ketamine and those treated with etomidate.

Medication and Fluid Management of Pediatric Sepsis and Septic Shock

Sepsis is a life-threatening response to infection that contributes significantly to neonatal and pediatric morbidity and mortality worldwide. The key tenets of care include early recognition of potential sepsis, rapid intervention with appropriate fluids to restore adequate tissue perfusion, and empiric antibiotics to cover likely pathogens. Vasoactive/inotropic agents are recommended if tissue perfusion and hemodynamics are inadequate following initial fluid resuscitation. Several adjunctive therapies have been suggested with theoretical benefit, though definitive recommendations are not yet supported by research reports. This review focuses on the recommendations for medication and fluid management of pediatric sepsis and septic shock, highlighting issues related to antibiotic choices and antimicrobial stewardship, selection of intravenous fluids for resuscitation, and selection and use of vasoactive/inotropic medications. Controversy remains regarding resuscitation fluid volume and type, antibiotic choices depending upon infectious risks in the patient's community, and adjunctive therapies such as vitamin C, corticosteroids, intravenous immunoglobulin, and methylene blue. We include best practice recommendations based on international guidelines, a review of primary literature, and a discussion of ongoing clinical trials and the nuances of therapeutic choices.

Multicenter Retrospective Review of Ketamine Use in the ICU

IMPORTANCE:

The response of ICU patients to continuously infused ketamine when it is used for analgesia and/or sedation remains poorly established.

OBJECTIVES:

To describe continuous infusion (CI) ketamine use in critically ill patients, including indications, dose and duration, adverse effects, patient outcomes, time in goal pain/sedation score range, exposure to analgesics/sedatives, and delirium.

DESIGN, SETTING, AND PARTICIPANTS:

Multicenter, retrospective, observational study from twenty-five diverse institutions in the United States. Patients receiving CI ketamine between January 2014 and December 2017.

MAIN OUTCOMES AND MEASURES:

Chart review evaluating institutional and patient demographics, ketamine indication, dose, administration, and adverse effects. Pain/sedation scores, cumulative doses of sedatives and analgesics, and delirium screenings in the 24 hours prior to ketamine were compared with those at 0–24 hours and 25–48 hours after.

RESULTS:

A total of 390 patients were included (median age, 54.5 yr; interquartile range, 39–65 yr; 61% males). Primary ICU types were medical (35.3%), surgical (23.3%), and trauma (17.7%). Most common indications were analgesia/sedation (n = 357, 91.5%). Starting doses were 0.2 mg/kg/hr (0.1–0.5 mg/kg/hr) and continued for 1.6 days (0.6–2.9 d). Hemodynamics in the first 4 hours after ketamine were variable (hypertension 24.0%, hypotension 23.5%, tachycardia 19.5%, bradycardia 2.3%); other adverse effects were minimal. Compared with 24 hours prior, there was a significant increase in proportion of time spent within goal pain score after ketamine initiation (24 hr prior: 68.9% [66.7–72.6%], 0–24 hr: 78.6% [74.3–82.5%], 25–48 hr: 80.3% [74.6–84.3%]; p < 0.001) and time spent within goal sedation score (24 hr prior: 57.1% [52.5–60.0%], 0–24 hr: 64.1% [60.7–67.2%], 25–48 hr: 68.9% [65.5–79.5%]; p < 0.001). There was also a significant reduction in IV morphine (mg) equivalents (24 hr prior: 120 [25–400], 0–24 hr: 118 [10–363], 25–48 hr: 80 [5–328]; p < 0.005), midazolam (mg) equivalents (24 hr prior: 11 [4–67], 0–24 hr: 6 [0–68], 25–48 hr: 3 [0–57]; p < 0.001), propofol (mg) (24 hr prior: 942 [223–4,018], 0–24 hr: 160 [0–2,776], 25–48 hr: 0 [0–1,859]; p < 0.001), and dexmedetomidine (µg) (24 hr prior: 1,025 [276–1,925], 0–24 hr: 285 [0–1,283], 25–48 hr: 0 [0–826]; p < 0.001). There was no difference in proportion of time spent positive for delirium (24 hr prior: 43.0% [17.0–47.0%], 0–24 hr: 39.5% [27.0–43.8%], 25–48 hr: 0% [0–43.7%]; p = 0.233). Limitations to these data include lack of a comparator group, potential for confounders and selection bias, and varying pain and sedation practices that may have changed since completion of the study.

CONCLUSIONS AND RELEVANCE:

There is variability in the use of CI ketamine. Hemodynamic instability was the most common adverse effect. In the 48 hours after ketamine initiation compared with the 24 hours prior, proportion of time spent in goal pain/sedation score range increased and exposure to other analgesics/sedatives decreased.

Hemodynamics in Helicopter Emergency Medical Services (HEMS) Patients Undergoing Rapid Sequence Intubation With Etomidate or Ketamine

BACKGROUND

Rapid sequence intubation (RSI) is performed by helicopter emergency medical services (HEMS) providers to establish airway control. Common induction agents are etomidate and ketamine, both touted to have relatively stable hemodynamic profiles. Limited data comparing these medications in the air medical setting exist.

OBJECTIVE

Compare administration of ketamine and etomidate on peri-intubation hemodynamics.

METHODS

A retrospective chart review of intubations performed by a HEMS program over 69 months was completed. Heart rate (HR) change, systolic blood pressure (SBP) change, and hypotension with etomidate or ketamine use were measured.

RESULTS

There were 258 patients induced with etomidate and 48 with ketamine. Etomidate patients showed a +1.161% change in HR (SD ± 22.7) and -0.49% change in SBP (SD ± 25.0). Ketamine patients showed a -4.7% change in HR (SD ± 16.7) and 17.2% change in SBP (SD ± 43.4). The p-values for percentage change in HR and SBP between etomidate and ketamine were 0.0830 and 0.0018, respectively. Twenty-five episodes of postadministration hypotension occurred with etomidate, and two with ketamine (p = 0.028).

CONCLUSION

Both ketamine and etomidate are appropriate for intubation of HEMS patients. Ketamine was preferentially selected for hypotensive patients with statistically significant improvement in SBP. Although statistically significant, both ketamine and etomidate had relative low incidences of hypotension.

Endotracheal intubation sedation in the intensive care unit

Endotracheal intubation is one of the most common, yet most dangerous procedure performed in the intensive care unit (ICU). Complications of ICU intubations include severe hypotension, hypoxemia, and cardiac arrest. Multiple observational studies have evaluated risk factors associated with these complications. Among the risk factors identified, the choice of sedative agents administered, a modifiable risk factor, has been reported to affect these complications (hypotension). Propofol, etomidate, and ketamine or in combination with benzodiazepines and opioids are commonly used sedative agents administered for endotracheal intubation. Propofol demonstrates rapid onset and offset, however, has drawbacks of profound vasodilation and associated cardiac depression. Etomidate is commonly used in the critically ill population. However, it is known to cause reversible inhibition of 11 β-hydroxylase which suppresses the adrenal production of cortisol for at least 24 h. This added organ impairment with the use of etomidate has been a potential contributing factor for the associated increased morbidity and mortality observed with its use. Ketamine is known to provide analgesia with sedation and has minimal respiratory and cardiovascular effects. However, its use can lead to tachycardia and hypertension which may be deleterious in a patient with heart disease or cause unpleasant hallucinations. Moreover, unlike propofol or etomidate, ketamine requires organ dependent elimination by the liver and kidney which may be problematic in the critically ill. Lately, a combination of ketamine and propofol, “Ketofol”, has been increasingly used as it provides a balancing effect on hemodynamics without any of the side effects known to be associated with the parent drugs. Furthermore, the doses of both drugs are reduced. In situations where a difficult airway is anticipated, awake intubation with the help of a fiberoptic scope or video laryngoscope is considered. Dexmedetomidine is a commonly used sedative agent for these procedures.

Anesthetic Considerations in Pediatric Patients With Acute Decompensated Heart Failure

Acute decompensated heart failure (ADHF) in pediatrics is a significant cause for morbidity and mortality in children. Congenital heart disease and cardiomyopathy are the leading etiologies of ADHF. It is common for these children to undergo diagnostic, therapeutic, or surgical procedure under anesthesia, which may be associated with significant morbidity and mortality. The importance of preanesthetic multidisciplinary planning with all involved teams, including anesthesia, cardiology, intensive care, perfusion, and cardiac surgery, cannot be emphasized enough. In order to safely manage these patients, it is imperative for the anesthesiologist to understand the complex pathophysiological interactions between cardiopulmonary systems and anesthesia during these procedures. This review discusses the etiology, pathophysiology, clinical manifestations, and perioperative management of these patients.

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.

Staying InformED: Top emergency Medicine pharmacotherapy articles of 2020

The year 2020 was not easy for Emergency Medicine (EM) clinicians with the burden of tackling a pandemic. A large focus, rightfully so, was placed on the evolving diagnosis and management of patients with COVID-19 and, as such, the ability of clinicians to remain up to date on key EM pharmacotherapy literature may have been compromised. This article reviews the most important EM pharmacotherapy publications indexed in 2020. A modified Delphi approach was utilized for selected journals to identify the most impactful EM pharmacotherapy studies. A total of fifteen articles, eleven trials and four meta-analyses, were identified. This review provides a summary of each study, along with a commentary on the impact to the EM literature and EM clinician.

Resuscitation of the Critically Ill Older Adult

In 30 years, adults 65 and older will represent 20% of the US population, with increased medical comorbidities leading to higher rates of critical illness and mortality. Despite significant acute illness, presenting symptoms and vital sign abnormalities may be subtle. Resuscitative guidelines are a helpful starting point but appropriate diagnostics, bedside ultrasound, and frequent reassessments are needed to avoid procrustean care that may worsen outcomes. Baseline functional status is as important as underlying comorbid conditions when prognosticating, and the patient's personal wishes should be sought early and throughout care with clear communication regarding prospects for immediate survival and overall recovery.

Practical approaches to sedation and analgesia in the newborn

The prevention, assessment, and treatment of neonatal pain and agitation continues to challenge clinicians and researchers. Substantial progress has been made in the past three decades, but numerous outstanding questions remain. In this setting, clinicians must establish safe and compassionate standardized practices that consider available efficacy data, long-term outcomes, and research gaps. Novel approaches with limited data must be carefully considered against historic standards of care with robust data suggesting limited benefit and clear adverse effects. This review summarizes available evidence while suggesting practical clinical approaches to pain assessment and avoidance, procedural analgesia, postoperative analgesia, sedation during mechanical ventilation and therapeutic hypothermia, and the issues of tolerance and withdrawal. Further research in all areas represents an urgent priority for optimal neonatal care. In the meantime, synthesis of available data offers clinicians challenging choices as they balance benefit and risk in vulnerable critically ill neonates.

Ketamine Prolonged Infusions in the Pediatric Intensive Care Unit: a Tertiary-Care Single-Center Analysis

OBJECTIVE

Ketamine is commonly used as an anesthetic and analgesic agent for procedural sedation, but there is little evidence on its current use as a prolonged continuous infusion in the PICU. We sought to analyze the use of ketamine as a prolonged infusion in critically ill children, its indications, dosages, efficacy, and safety.

METHODS

We retrospectively reviewed the clinical charts of patients receiving ketamine for ≥24 hours in the period 2017-2018 in our tertiary care center. Data on concomitant treatments pre and 24 hours post ketamine introduction and adverse events were also collected.

RESULTS

Of the 60 patients included, 78% received ketamine as an adjuvant of analgosedation, 18% as an adjuvant of bronchospasm therapy, and 4% as an antiepileptic treatment. The median infusion duration was 103 hours (interquartile range [IQR], 58-159; range, 24-287), with median dosages between 15 (IQR, 10-20; range, 5-47) and 30 (IQR, 20-50; range, 10-100) mcg/kg/min. At 24 hours of ketamine infusion, dosages/kg/hr of opioids significantly decreased (p < 0.001), and 81% of patients had no increases in dosages of concomitant analgosedation. For 27% of patients with bronchospasm, the salbutamol infusions were lowered at 24 hours after ketamine introduction. Electroencephalograms of epileptic patients (n = 2) showed resolution of status epilepticus after ketamine administration. Adverse events most likely related to ketamine were hypertension (n = 1), hypersalivation (n = 1), and delirium (n = 1).

CONCLUSIONS

Ketamine can be considered a worthy strategy for the analgosedation of difficult-to-sedate patients. Its use for prolonged sedation allows the sparing of opioids. Its efficacy in patients with bronchospasm or status epilepticus still needs to be investigated.

Ketamine Versus Etomidate and Peri-intubation Hypotension: A National Emergency Airway Registry Study

BACKGROUND

The hemodynamic impact of induction agents is a critically important consideration in emergency intubations. We assessed the relationship between peri-intubation hypotension and the use of ketamine versus etomidate as an induction agent for emergency department (ED) intubation.

METHODS

We analyzed ED intubation data for patients aged >14 years from the National Emergency Airway Registry performed in 25 EDs during 2016 through 2018. We excluded patients with preintubation hypotension (systolic blood pressure <100 mm Hg) or cardiac arrest prior to intubation. The primary outcome was peri-intubation hypotension. Secondary outcomes included interventions for hypotension (e.g., intravenous fluids or vasopressors). We report adjusted odds ratios (aOR) from multivariable logistic regression models controlling for patient demographics, difficult airway characteristics, and intubation modality.

RESULTS

There were 738 encounters with ketamine and 6,068 with etomidate. Patients receiving ketamine were more likely to have difficult airway characteristics (effect size difference = 8.8%, 95% confidence interval [CI] = 5.3% to 12.4%) and to undergo intubation with video laryngoscopy (8.1%, 95% CI = 4.4% to 12.0%). Peri-intubation hypotension incidence was 18.3% among patients receiving ketamine and 12.4% among patients receiving etomidate (effect size difference = 5.9%, 95% CI = 2.9% to 8.8%). Patients receiving ketamine were more likely to receive treatment for peri-intubation hypotension (effect size difference = 6.5%, 95% CI = 3.9% to 9.3%). In logistic regression analyses, patients receiving ketamine remained at higher risk for peri-intubation hypotension (aOR = 1.4, 95% CI = 1.2 to 1.7) and treatment for hypotension (aOR = 1.8, 95% CI = 1.4 to 2.0). There was no difference in the aOR of hypotension between patients receiving ketamine at doses ≤1.0 mg/kg versus >1.0 mg/kg or patients receiving etomidate at doses ≤0.3 mg/kg versus >0.3 mg/kg.

CONCLUSIONS

Pending additional data, our results suggest that clinicians should not necessarily prioritize ketamine over etomidate based on concern for hemodynamic compromise among ED patients undergoing intubation.

Etomidate Use Is Associated With Less Hypotension Than Ketamine for Emergency Department Sepsis Intubations: A NEAR Cohort Study

OBJECTIVE

The objectives of this study were 1) to describe the current use of etomidate and other induction agents in patients with sepsis and 2) to compare adverse events between etomidate and ketamine in sepsis.

METHODS

This was an observational cohort study of the prospective National Emergency Airway Registry (NEAR) data set. Descriptive statistics were used to report the distribution of induction agents used in patients with sepsis. Adverse events were compared using bivariate analysis, and a sensitivity analysis was conducted using a propensity score-adjusted analysis of etomidate versus ketamine.

RESULTS

A total of 531 patients were intubated for sepsis, and the majority (71%) were intubated with etomidate as the initial induction agent. Etomidate was less frequently used in sepsis patients than nonsepsis patients (71% vs. 85%, odds ratio [OR] = 0.4, 95% confidence interval [CI] = 0.4 to 0.5). Sepsis patients had a greater risk of adverse events, and vasopressor therapy was required for 25% of patients after intubation. Postprocedure hypotension was higher between those intubated for sepsis with ketamine versus etomidate (74% vs. 50%, OR = 2.9, 95% CI = 1.9 to 4.5). After confounding by indication in the propensity score-adjusted analysis was accounted for, ketamine was associated with more postprocedure hypotension (OR = 2.7, 95% CI = 1.1 to 6.7). No difference in emergency department deaths was observed.

CONCLUSIONS

Etomidate is used less frequently in sepsis patients than nonsepsis patients, with ketamine being the most frequently used alternative. Ketamine was associated with more postprocedural hypotension than etomidate. Future clinical trials are needed to determine the optimal induction agent in patients with sepsis.

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.

The Right Ventricle-You May Forget it, but It Will Not Forget You

Right ventricular (RV) dysfunction and failure are common and often overlooked causes of perioperative deterioration and adverse outcomes. Due to its unique pathophysiologic underpinnings, RV failure often does not respond to typical therapeutic measures such as volume resuscitation and often worsens when therapy is escalated and mechanical ventilation is begun, with a danger of irreversible cardiovascular collapse and death. The single most important factor in improving outcomes in the context of RV failure is anticipating and recognizing it. Once established, a vicious circle of systemic hypotension, and RV ischemia and dilation is set in motion, rapidly spiraling down into a state of shock culminating in multi-organ failure and ultimately death. Therapy of RV failure must focus on rapidly reestablishing RV coronary perfusion, lowering pulmonary vascular resistance and optimizing volemia. In parallel, underlying reversible causes should be sought and if possible treated. In all stages of diagnostics and therapy, echocardiography plays a central role. In severe cases of RV dysfunction there remains a role for the use of the pulmonary artery catheter. When these mostly simple measures are undertaken in a timely fashion, the spiral of death of RV failure can often be broken or even prevented altogether.

Anesthesia for Patients with Extensive Trauma

Trauma anesthesiology is a unique and growing subspecialty. With the growing number of adult and pediatric trauma centers in the United States, a thorough understanding of the early management of severely injured patients with trauma is an important aspect of anesthesia. Trauma anesthesiology requires the ability to adapt to different work environments, including the trauma bay, the operating room, and even the intensive care unit, where a patient room may require conversion to an operating suite for emergencies. This article provides a review of the anesthetic management for patients with extensive trauma, focusing on physiology, pharmacology, and bedside management.

[Drugs for intravenous induction of anesthesia: ketamine, midazolam and synopsis of current hypnotics]

Ketamine and midazolam form the endpoint of a series of articles about intravenous induction of anesthesia . Both substances can be used as single induction hypnotic drugs; however, in practice, this is unusual. Both substances, with the exception of a few very specific indications and clinical situations, are more frequently used in combination or with one of the more common alternatives propofol, barbiturates and etomidate. The reasons are the activity and side effects of both substances and their positive characteristics are used more as a supplement. In the concluding comparison the five discussed induction hypnotics are judged against each other. The use in certain clinical constellations and in special patient populations is evaluated individually for each substance. It is highlighted which drug appears most appropriate in which situation. As methohexital is nowadays only administered in very few clinical situations, this substance is not included in the comparative assessment.

Profound Bradycardia and Cardiac Arrest After Sugammadex Administration in a Previously Healthy Patient: A Case Report

We report the case of a 60-year-old man who underwent open radical prostatectomy for prostate adenocarcinoma. He had no known cardiac disease or symptoms other than controlled hypertension and remote history of cocaine use. The patient was given sugammadex for reversal of neuromuscular blockade and, within 1 minute, developed severe, drug-resistant bradycardia followed by pulseless electrical activity arrest. Advanced cardiac life support was initiated and continued for 15 minutes before the return of spontaneous circulation. Subsequent cardiac workup showed no abnormalities. We believe the cause of arrest was sugammadex, considering the time of administration, the absence of cardiac disease, and stable operative course.

Potential consequences of high-dose infusion of ketamine for refractory status epilepticus: case reports and systematic literature review

Our goal was to provide comprehensive data on the effectiveness of ketamine in refractory status epilepticus (RSE) and to describe the potential consequences of long-term ketamine infusion. Ketamine, an N-methyl D-aspartate (NMDA) receptor antagonist, blocks excitatory pathways contributing to ongoing seizure. While ketamine use is standard in anaesthetic induction, no definitive protocol exists for its use in RSE, and little is known about its adverse effects in long-term, high-dose administration. We present two cases of RSE that responded rapidly to ketamine infusion, both with fatal outcomes secondary to metabolic acidosis and cardiovascular collapse. We performed a systematic review of the application and consequences of ketamine use in RSE. PubMed, Ovid, MEDLINE and PMC were searched for articles describing ketamine treatment for RSE according to a predetermined search strategy and inclusion criteria. The systematic review revealed wide discrepancies in ketamine dosing (infusion maintenance dose range 0.0075-10.5 mg/kg/hour), but good outcomes in medically managed RSE (75% of studies reported moderate or complete seizure control in adults, 62.5% in paediatrics). Additionally, literature review elucidated a potentially causal relationship between prolonged ketamine infusion and both cardiovascular and metabolic dysregulation. Ketamine is effective in RSE by antagonising excitotoxic NMDA receptors. However, there is high variability in ketamine dosing and scarce data on its safety in long-term infusion. Metabolic acidosis and haemodynamic instability associated with the use of long-term, high-dose ketamine infusions must be of concern to clinicians administering ketamine to critically ill patients.

Resuscitation Resequenced: A Rational Approach to Patients with Trauma in Shock

Trauma resuscitation is a complex and dynamic process that requires a high-performing team to optimize patient outcomes. More than 30 years ago, Advanced Trauma Life Support was developed to formalize and standardize trauma care; however, the sequential nature of the algorithm that is used can lead to ineffective prioritization. An improved understanding of shock mandates an updated approach to trauma resuscitation. This article proposes a resequenced approach that (1) addresses immediate threats to life and (2) targets strategies for the diagnosis and management of shock causes. This updated approach emphasizes evidence-based resuscitation principles that align with physiologic priorities.

Ketamine infusion for refractory status epilepticus: A case report of cardiac arrest

BACKGROUND

Refractory status epilepticus (RSE) has a high mortality rate and is often difficult to treat. When traditional therapies fail ketamine may be considered. There are limited reports of adverse cardiac events with the use of ketamine for RSE and no reports of cardiac arrest in this context.

OBJECTIVE

Evaluate the occurrence of cardiac arrhythmias associated with the use of ketamine for RSE.

METHODS

Retrospective chart review of nine patients who underwent ketamine infusion for RSE.

RESULTS

Etiology of refractory status epilepticus included autoimmune/infectious process (Zeiler et al., 2014), ischemic stroke (Bleck, 2005) and subarachnoid hemorrhage (Bleck, 2005). Of the nine patients who received ketamine, two had documented cardiac events; one remained clinically stable and the other developed multiple arrhythmias, including recurrent episodes of asystole. Once ketamine was discontinued the latter patient stabilized with the addition of anti arrhythmic therapy.

CONCLUSION

Ketamine is utilized to treat refractory status epilepticus, but should be used with caution in patients with subarachnoid hemorrhage, as there may be an increased risk of life threatening arrhythmias and cardiac arrest.

Comparison of Etomidate and Ketamine for Induction During Rapid Sequence Intubation of Adult Trauma Patients

STUDY OBJECTIVE

Induction doses of etomidate during rapid sequence intubation cause transient adrenal dysfunction, but its clinical significance on trauma patients is uncertain. Ketamine has emerged as an alternative for rapid sequence intubation induction. Among adult trauma patients intubated in the emergency department, we compare clinical outcomes among those induced with etomidate and ketamine.

METHODS

The study entailed a retrospective evaluation of a 4-year (January 2011 to December 2014) period spanning an institutional protocol switch from etomidate to ketamine as the standard induction agent for adult trauma patients undergoing rapid sequence intubation in the emergency department of an academic Level I trauma center. The primary outcome was hospital mortality evaluated with multivariable logistic regression, adjusted for age, vital signs, and injury severity and mechanism. Secondary outcomes included ICU-free days and ventilator-free days evaluated with multivariable ordered logistic regression using the same covariates.

RESULTS

The analysis included 968 patients, including 526 with etomidate and 442 with ketamine. Hospital mortality was 20.4% among patients induced with ketamine compared with 17.3% among those induced with etomidate (adjusted odds ratio [OR] 1.41; 95% confidence interval [CI] 0.92 to 2.16). Patients induced with ketamine had ICU-free days (adjusted OR 0.80; 95% CI 0.63 to 1.00) and ventilator-free days (adjusted OR 0.96; 95% CI 0.76 to 1.20) similar to those of patients induced with etomidate.

CONCLUSION

In this analysis spanning an institutional protocol switch from etomidate to ketamine as the standard rapid sequence intubation induction agent for adult trauma patients, patient-centered outcomes were similar for patients who received etomidate and ketamine.

Ketamine: 50 Years of Modulating the Mind

Ketamine was introduced into clinical practice in the 1960s and continues to be both clinically useful and scientifically fascinating. With considerably diverse molecular targets and neurophysiological properties, ketamine’s effects on the central nervous system remain incompletely understood. Investigators have leveraged the unique characteristics of ketamine to explore the invariant, fundamental mechanisms of anesthetic action. Emerging evidence indicates that ketamine-mediated anesthesia may occur via disruption of corticocortical information transfer in a frontal-to-parietal (“top down”) distribution. This proposed mechanism of general anesthesia has since been demonstrated with anesthetics in other pharmacological classes as well. Ketamine remains invaluable to the fields of anesthesiology and critical care medicine, in large part due to its ability to maintain cardiorespiratory stability while providing effective sedation and analgesia. Furthermore, there may be an emerging role for ketamine in treatment of refractory depression and Post-Traumatic Stress Disorder. In this article, we review the history of ketamine, its pharmacology, putative mechanisms of action and current clinical applications.

Ketamine-mediated afferent-specific presynaptic transmission blocks in low-threshold and sex-specific subpopulation of myelinated Ah-type baroreceptor neurons of rats

Background

Ketamine enhances autonomic activity, and unmyelinated C-type baroreceptor afferents are more susceptible to be blocked by ketamine than myelinated A-types. However, the presynaptic transmission block in low-threshold and sex-specific myelinated Ah-type baroreceptor neurons (BRNs) is not elucidated.

Methods

Action potentials (APs) and excitatory post-synaptic currents (EPSCs) were investigated in BRNs/barosensitive neurons identified by conduction velocity (CV), capsaicin-conjugated with Iberiotoxin-sensitivity and fluorescent dye using intact nodose slice and brainstem slice in adult female rats. The expression of mRNA and targeted protein for NMDAR1 was also evaluated.

Results

Ketamine time-dependently blocked afferent CV in Ah-types in nodose slice with significant changes in AP discharge. The concentration-dependent inhibition of ketamine on AP discharge profiles were also assessed and observed using isolated Ah-type BRNs with dramatic reduction in neuroexcitability. In brainstem slice, the 2^nd-order capsaicin-resistant EPSCs were identified and ∼50% of them were blocked by ketamine concentration-dependently with IC₅₀ estimated at 84.4 μM compared with the rest (708.2 μM). Interestingly, the peak, decay time constant, and area under curve of EPSCs were significantly enhanced by 100 nM iberiotoxin in ketamine-more sensitive myelinated NTS neurons (most likely Ah-types), rather than ketamine-less sensitive ones (A-types).

Conclusions

These data have demonstrated, for the first time, that low-threshold and sex-specific myelinated Ah-type BRNs in nodose and Ah-type barosensitive neurons in NTS are more susceptible to ketamine and may play crucial roles in not only mean blood pressure regulation but also buffering dynamic changes in pressure, as well as the ketamine-mediated cardiovascular dysfunction through sexual-dimorphic baroreflex afferent pathway.

Sedation in Critically Ill Children with Respiratory Failure

This article discusses the rationale of sedation in respiratory failure, sedation goals, how to assess the need for sedation as well as effectiveness of interventions in critically ill children, with validated observational sedation scales. The drugs and non-pharmacological approaches used for optimal sedation in ventilated children are reviewed, and specifically the rationale for drug selection, including short- and long-term efficacy and safety aspects of the selected drugs. The specific pharmacokinetic and pharmacodynamic aspects of sedative drugs in the critically ill child and consequences for dosing are presented. Furthermore, we discuss different sedation strategies and their adverse events, such as iatrogenic withdrawal syndrome and delirium. These principles can guide clinicians in the choice of sedative drugs in pediatric respiratory failure.

The Physiologically Difficult Airway

Airway management in critically ill patients involves the identification and management of the potentially difficult airway in order to avoid untoward complications. This focus on difficult airway management has traditionally referred to identifying anatomic characteristics of the patient that make either visualizing the glottic opening or placement of the tracheal tube through the vocal cords difficult. This paper will describe the physiologically difficult airway, in which physiologic derangements of the patient increase the risk of cardiovascular collapse from airway management. The four physiologically difficult airways described include hypoxemia, hypotension, severe metabolic acidosis, and right ventricular failure. The emergency physician should account for these physiologic derangements with airway management in critically ill patients regardless of the predicted anatomic difficulty of the intubation.

Etomidate in pediatric anesthesiology: Where are we now?

Etomidate is an intravenous anesthetic agent released for clinical use in the United States in 1972. Its popularity in clinical practice is the result of its beneficial effects on intracerebral dynamics with limited effects on hemodynamic function. These properties have made it a safe and effective anesthetic induction agent in both adult and pediatric patients with altered myocardial performance, congenial heart disease, or hypovolemia. However, recent concern has been expressed regarding its effects on the endogenous production of corticosteroids and the impact of that effect on patient outcomes. The following manuscript reviews clinical reports regarding etomidate use in the pediatric population and discusses recent concerns regarding its effects on corticosteroid metabolism and the implications of such effects for clinical use.

Ketamine/propofol admixture (ketofol) at induction in the critically ill against etomidate (KEEP PACE trial): study protocol for a randomized controlled trial

BACKGROUND

Endotracheal intubation (ETI) is commonly performed as a life-saving procedure in the intensive care unit (ICU). It is often associated with significant hemodynamic perturbations and can severely impact the outcome of ICU patients. Etomidate is often chosen by many critical care providers for the patients who are hypotensive because of its superior hemodynamic profile compared to other induction medications. However, recent evidence has raised concerns about the increased incidence of adrenal insufficiency and mortality associated with etomidate use. A combination of ketamine and propofol (known as ketofol) has been studied in various settings as an alternative induction agent. In recent years, studies have shown that this combination may provide adequate sedation while maintaining hemodynamic stability, based on the balancing of the hemodynamic effects of these two individual agents. We hypothesized that ketofol may offer a valuable alternative to etomidate in critically ill patients with or without hemodynamic instability.

METHODS/DESIGN

A randomized controlled parallel-group clinical trial of adult critically ill patients admitted to either a medical or surgical ICU at Mayo Clinic in Rochester, MN will be conducted. As part of planned emergency research, informed consent will be waived after appropriate community consultation and notification. Patients undergoing urgent or emergent ETI will receive either etomidate or a 1:1 admixture of ketamine and propofol (ketofol). The primary outcome will be hemodynamic instability during the first 15 minutes following drug administration. Secondary outcomes will include ICU length of stay, mortality, adrenal function, ventilator-free days and vasoactive medication use, among others. The planned sample size is 160 total patients.

DISCUSSION

The overall goal of this trial is to assess the hemodynamic consequences of a ketamine-propofol combination used in critically ill patients undergoing urgent or emergent ETI compared to etomidate, a medication with an established hemodynamic profile. The trial will address a crucial gap in the literature regarding the optimal induction agent for ETI in patients that may have potential or established hemodynamic instability. Greater experience with planned emergency research will, hopefully, pave the way for future prospective randomized clinical trials in the critically ill population.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT02105415. 31 March 2014.

Factors associated with the occurrence of cardiac arrest after emergency tracheal intubation in the emergency department

OBJECTIVES

Emergency tracheal intubation has achieved high success and low complication rates in the emergency department (ED). The objective of this study was to evaluate the incidence of post-intubation CA and determine the clinical factors associated with this complication.

METHODS

A matched case-control study with a case to control ratio of 1:3 was conducted at an urban tertiary care center between January 2007 and December 2011. Critically ill adult patients requiring emergency airway management in the ED were included. The primary endpoint was post-intubation CA, defined as CA within 10 minutes after tracheal intubation. Clinical variables were compared between patients with post-intubation CA and patients without CA who were individually matched based on age, sex, and pre-existing comorbidities.

RESULTS

Of 2,403 patients who underwent emergency tracheal intubation, 41 patients (1.7%) had a post-intubation CA within 10 minutes of the procedure. The most common initial rhythm was pulseless electrical activity (78.1%). Patients experiencing CA had higher in-hospital mortality than patients without CA (61.0% vs. 30.1%; p<0.001). Systolic hypotension prior to intubation, defined as a systolic blood pressure ≤ 90 mmHg, was independently associated with post-intubation CA (OR, 3.67 [95% CI, 1.58-8.55], p = 0.01).

CONCLUSION

Early post-intubation CA occurred with an approximate 2% frequency in the ED. Systolic hypotension before intubation is associated with this complication, which has potentially significant implications for clinicians at the time of intubation.

Ventricular tachycardia after ketamine sedation for fracture reduction

This case report describes a 10-year-old female patient who underwent ketamine sedation for fracture reduction and experienced asymptomatic ventricular tachycardia after the sedation. She had no history of syncope, chest pain, palpations, or light-headedness and had a normal physical examination. This is the first reported case of a patient experiencing ventricular tachycardia after ketamine use for sedation. This case demonstrates a serious and potentially harmful possible adverse effect of ketamine administration.

Site-level variance for adverse tracheal intubation-associated events across 15 North American PICUs: a report from the national emergency airway registry for children*

OBJECTIVE

Tracheal intubation in PICUs is associated with adverse tracheal intubation-associated events. Patient, provider, and practice factors have been associated with tracheal intubation-associated events; however, site-level variance and the association of site-level characteristics on tracheal intubation-associated event outcomes are unknown. We hypothesize that site-level variance exists in the prevalence of tracheal intubation-associated events and that site characteristics may affect outcomes.

DESIGN

Prospective observational cohort study.

SETTING

Fifteen PICUs in North America.

SUBJECTS

Critically ill pediatric patients requiring tracheal intubation.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

Tracheal intubation quality improvement data were collected in 15 PICUs from July 2010 to December 2011 using a National Emergency Airway Registry for Children with robust site-specific compliance. Tracheal intubation-associated events and severe tracheal intubation-associated events were explicitly defined a priori. We analyzed the association of site-level variance with tracheal intubation-associated events using univariate analysis and adjusted for previously identified patient- and provider-level risk factors. Analysis of 1,720 consecutive intubations revealed an overall prevalence of 20% tracheal intubation-associated events and 6.5% severe tracheal intubation-associated events, with considerable site variability ranging from 0% to 44% tracheal intubation-associated events and from 0% to 20% severe tracheal intubation-associated events. Larger PICU size (> 26 beds) was associated with fewer tracheal intubation-associated events (18% vs 23%, p = 0.006), but the presence of a fellowship program was not (20% vs 18%, p = 0.58). After adjusting for patient and provider characteristics, both PICU size and fellowship presence were not associated with tracheal intubation-associated events (p = 0.44 and p = 0.18, respectively). Presence of mixed ICU with cardiac surgery was independently associated with a higher prevalence of tracheal intubation-associated events (25% vs 15%; p < 0.001; adjusted odds ratio, 1.81; 95% CI, 1.29-2.53; p = 0.01). Substantial site-level variance was observed in medication use, which was not explained by patient characteristic differences.

CONCLUSIONS

Substantial site-level variance exists in tracheal intubation practice, tracheal intubation-associated events, and severe tracheal intubation-associated events. Neither PICU size nor fellowship training program explained site-level variance. Interventions to reduce tracheal intubation-associated event prevalence and severity will likely need to be contextualized to variability in individual ICUs patients, providers, and practice.

Safety of Propofol as an Induction Agent for Urgent Endotracheal Intubation in the Medical Intensive Care Unit

Purpose:

Propofol is known to provide excellent intubation conditions without the use of neuromuscular blocking agents. However, propofol has adverse effects that may limit its use in the critically ill patients, particularly in the hemodynamically unstable patient. We report on the safety and efficacy of propofol for use as an agent for urgent endotracheal intubation (UEI) in the critically ill patients.

Methods:

We reviewed the outcomes of 472 consecutive UEIs performed by a medical intensive care unit (ICU) team at a tertiary care hospital from November 2008 through November 2012. Outcome data were collected prospectively as part of an ongoing quality improvement project.

Results:

Propofol was used as the sole sedative agent in 409 (87%) of the 472 patients. In 18 (4%) of the 472 patients, other agents (midazolam, lorazepam, or etomidate) were used in addition to propofol. Of the 472, 10 (2%) intubations were performed with a sedative agent other than propofol, and 35 (7%) of the 472 intubations were performed without any sedating agent. Endotracheal tube insertion was successful in all 472 patients. Complications of UEI in those patients who received propofol were as follows: desaturation (Sao2 < 80%) 30 (7%) of the 427, hypotension (systolic blood pressure < 70 mm Hg) 19 (4%) of the 427, difficult intubation (>2 attempts) 44 (10%) of the 427, esophageal intubation 24 (6%) of the 427, aspiration 6 (1%) of the 427, and oropharyngeal injury 4 (1%) of the 427. There were no deaths. Average dose of propofol was 99 mg (standard deviation 7.39) per person.

Conclusions:

Our results compare favorably with the complication rate of UEI reported in the critical care and anesthesiology literature and indicate that propofol is a useful agent for airway management in the ICU.

Pro-con debate: etomidate or ketamine for rapid sequence intubation in pediatric patients

When caring for critically ill children, airway management remains a primary determinant of the eventual outcome. Airway control with endotracheal intubation is frequently necessary. Rapid sequence intubation (RSI) is generally used in emergency airway management to protect the airway from passive regurgitation of gastric contents. Along with a rapid acting neuromuscular blocking agent, sedation is an essential element of RSI. A significant safety concern regarding sedatives is the risk of hypotension and cardiovascular collapse, especially in critically ill patients or those with pre-existing comorbid conditions. Ketamine and etomidate, both of which provide effective sedation with limited effects on hemodynamic function, have become increasingly popular as induction agents for RSI. However, experience and clinical investigations have raised safety concerns associated with both etomidate and ketamine. Using a pro-con debate style, the following manuscript discusses the use of ketamine versus etomidate in RSI.