An investigation into emergency medicine resident cricothyrotomy competency: Is three the magic number?

Objectives

Cricothyrotomy is a high-stakes emergency procedure. Because the procedure is rare, simulation is often used to train residents. The Accreditation Council for Graduate Medical Education (ACGME) requires performance of three cricothyrotomies during residency, but the optimal number of training repetitions is unknown. Additional repetitions beyond three could increase proficiency, though it is unknown whether there is a threshold beyond which there is no benefit to additional repetition. The objective of this study was to establish a minimum number of simulated cricothyrotomy attempts beyond which additional attempts did not increase proficiency.

Methods

This was a prospective, observational study conducted over 3 years at the simulation center of an academic emergency medicine residency program. Participants were residents participating in a cricothyrotomy training as part of a longitudinal airway curriculum course. The primary outcome was time to successful completion of the procedure as first-year residents. Secondary outcomes included time to completion as second- and third-year residents. Procedure times were plotted as a function of attempt number. Data were analyzed using descriptive statistics, repeated-measures analysis of variance, and correlation analysis. Preprocedure surveys collected further data regarding procedure experience, confidence, and comfort.

Results

Sixty-nine first-year residents participated in the study. Steady improvement in time to completion was seen through the first six attempts (from a mean of 75 to 41 sec), after which no further significant improvement was found. Second- and third-year residents initially demonstrated slower performance than first-year residents but rapidly improved to surpass their first-year performance. Resident mean times at five attempts were faster with each year of residency (first-year 48 sec, second-year 30 sec, third-year 24 sec). There was no statistically significant correlation between confidence and time to complete the procedure.

Conclusions

Additional repetition beyond the ACGME-endorsed three cricothyrotomy attempts may help increase proficiency. Periodic retraining may be important to maintain skills.

Effect of inclined positioning on first-pass success during endotracheal intubation: a systematic review and meta-analysis

BACKGROUND

Endotracheal intubation is a high-risk procedure. Optimisation of all aspects of the procedure, including patient positioning, is important to facilitate success and minimise complications. The objective of this systematic review was to determine the association between inclined patient positioning and first-pass success and other clinically important outcomes among patients undergoing endotracheal intubation.

METHODS

A search of PubMed, CINAHL, SCOPUS, EMBASE and Cochrane, from inception through October 2020 was conducted. Studies were assessed independently by two authors to determine eligibility for inclusion. Included studies were any randomised or observational study that compared supine to inclined patient positioning for endotracheal intubation and assessed one of our predefined outcomes. Simulation studies were excluded. Study results were meta-analysed using a random effects model. The quality of the evidence for outcomes of interest was assessed using the Grading of Recommendations, Assessment, Development and Evaluations approach.

RESULTS

A total of 5113 studies were identified, of which 10 studies representing 18 371 intubations were included for meta-analysis. There was no statistically significant difference in the primary outcome of first-pass success rate (relative risk 1.02, 95% CI 0.98 to 1.05) or secondary outcomes of oesophageal intubation, glottic view, hypotension, hypoxaemia, mortality or peri-intubation arrest. Likewise, there were no statistically significant differences in any of the outcomes in predefined subgroup analyses of randomised controlled trials, intubations in acute settings or intubations performed with >45 degrees of incline. Overall quality of evidence was rated as low or very low for most outcomes.

CONCLUSIONS

This systematic review and meta-analysis found no evidence of benefit or harm with inclined versus supine patient positioning during endotracheal intubation in any setting.

Sepsis with liver dysfunction and coagulopathy predicts an inflammatory pattern of macrophage activation

Background

Interleukin-1 receptor antagonists can reduce mortality in septic shock patients with hepatobiliary dysfunction and disseminated intravascular coagulation (HBD + DIC), an organ failure pattern with inflammatory features consistent with macrophage activation. Identification of clinical phenotypes in sepsis may allow for improved care. We aim to describe the occurrence of HBD + DIC in a contemporary cohort of patients with sepsis and determine the association of this phenotype with known macrophage activation syndrome (MAS) biomarkers and mortality. We performed a retrospective nested case–control study in adult septic shock patients with concurrent HBD + DIC and an equal number of age-matched controls, with comparative analyses of all-cause mortality and circulating biomarkers between the groups. Multiple logistic regression explored the effect of HBD + DIC on mortality and the discriminatory power of the measured biomarkers for HBD + DIC and mortality.

Results

Six percent of septic shock patients (n = 82/1341) had HBD + DIC, which was an independent risk factor for 90-day mortality (OR = 3.1, 95% CI 1.4–7.5, p = 0.008). Relative to sepsis controls, the HBD + DIC cohort had increased levels of 21 of the 26 biomarkers related to macrophage activation (p < 0.05). This panel was predictive of both HBD + DIC (sensitivity = 82%, specificity = 84%) and mortality (sensitivity = 92%, specificity = 90%).

Conclusion

The HBD + DIC phenotype identified patients with high mortality and a molecular signature resembling that of MAS. These observations suggest trials of MAS-directed therapies are warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40635-022-00433-y.

Effect of an Aerosol Box on Intubation in Simulated Emergency Department Airways: A Randomized Crossover Study

INTRODUCTION

The use of transparent plastic aerosol boxes as protective barriers during endotracheal intubation has been advocated during the severe acute respiratory syndrome coronavirus 2 pandemic. There is evidence of worldwide distribution of such devices, but some experts have warned of possible negative impacts of their use. The objective of this study was to measure the effect of an aerosol box on intubation performance across a variety of simulated difficult airway scenarios in the emergency department.

METHODS

This was a randomized, crossover design study. Participants were randomized to intubate one of five airway scenarios with and without an aerosol box in place, with randomization of intubation sequence. The primary outcome was time to intubation. Secondary outcomes included number of intubation attempts, Cormack-Lehane view, percent of glottic opening, and resident physician perception of intubation difficulty.

RESULTS

Forty-eight residents performed 96 intubations. Time to intubation was significantly longer with box use than without (mean 17 seconds [range 6-68 seconds] vs mean 10 seconds [range 5-40 seconds], p <0.001). Participants perceived intubation as being significantly more difficult with the aerosol box. There were no significant differences in the number of attempts or quality of view obtained.

CONCLUSION

Use of an aerosol box during difficult endotracheal intubation increases the time to intubation and perceived difficulty across a range of simulated ED patients.

Association of Checklist Use in Endotracheal Intubation With Clinically Important Outcomes: A Systematic Review and Meta-analysis

IMPORTANCE

Endotracheal intubation of critically ill patients is a high-risk procedure. Checklists have been advocated to improve outcomes.

OBJECTIVE

To assess whether the available evidence supports an association of use of airway checklists with improved clinical outcomes in patients undergoing endotracheal intubation.

DATA SOURCES

For this systematic review and meta-analysis, PubMed (OVID), Embase, Cochrane, CINAHL, and SCOPUS were searched without limitations using the Medical Subject Heading terms and keywords airway; management; airway management; intubation, intratracheal; checklist; and quality improvement to identify studies published between January 1, 1960, and June 1, 2019. A supplementary search of the gray literature was performed, including conference abstracts and clinical trial registries.

STUDY SELECTION

Full-text reviews were performed to determine final eligibility for inclusion. Included studies were randomized clinical trials or observational human studies that compared checklist use with any comparator for endotracheal intubation and assessed 1 of the predefined outcomes.

DATA EXTRACTION AND SYNTHESIS

Data extraction and quality assessment were performed using the Newcastle-Ottawa Scale for observational studies and Cochrane risk of bias tool for randomized clinical trials. Study results were meta-analyzed using a random-effects model. Reporting of this study follows the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

MAIN OUTCOMES AND MEASURES

The primary outcome was mortality. Secondary outcomes included first-pass success and known complications of endotracheal intubation, including esophageal intubation, hypoxia, hypotension, and cardiac arrest.

RESULTS

The search identified 1649 unique citations of which 11 (3261 patients) met the inclusion criteria. One randomized clinical trial and 3 observational studies had a low risk of bias. Checklist use was not associated with decreased mortality (5 studies [2095 patients]; relative risk, 0.97; 95% CI, 0.80-1.18; I2 = 0%). Checklist use was associated with a decrease in hypoxic events (8 studies [3010 patients]; relative risk, 0.75; 95% CI, 0.59-0.95; I2 = 33%) but no other secondary outcomes. Studies with a low risk of bias did not demonstrate decreased hypoxia associated with checklist use.

CONCLUSIONS AND RELEVANCE

The findings suggest that use of airway checklists is not associated with improved clinical outcomes during and after endotracheal intubation, which may affect practitioners' decision to use checklists in this setting.

Frequency of safety net errors in the emergency department: Effect of patient handoffs

OBJECTIVES

The objective of this study was to determine physician awareness of abnormal vital signs and key clinical interventions (oxygen provision, intravenous access) in the emergency department, and to measure the effect of patient handoffs on this awareness.

METHODS

This was a prospective observational study at two large, urban, academic emergency departments. Emergency department physicians were asked the following about each of the physician's patients: 1) the number of IV lines, 2) whether the patient was on supplemental oxygen, and 3) whether the patient had any abnormal vital signs. Physicians were blind to the nature of the study prior to enrollment. Error rates between physician responses and actual patient status were calculated, and logistic regression, adjusted for physician clustering, was used to calculate association of errors with multiple situational factors, including handoff status.

RESULTS

We analyzed 463 patient encounters from 74 physicians. Physicians missed abnormal vital signs in 19.4% of encounters. They made errors in oxygen status and number of IV lines in 16.6% and 35.8% of encounters, respectively. Physicians were significantly more likely to make all types of errors on patients who had undergone handoff as opposed to their primary patients.

CONCLUSION

Emergency physicians make frequent errors regarding awareness of their patients' vital signs, oxygen and vascular status and patient handoffs are associated with an increased frequency of such errors.

Cross-over study of novice intubators performing endotracheal intubation in an upright versus supine position

There are a number of potential physical advantages to performing orotracheal intubation in an upright position. The objective of this study was to measure the success of intubation of a simulated patient in an upright versus supine position by novice intubators after brief training. This was a cross-over design study in which learners (medical students, physician assistant students, and paramedic students) intubated mannequins in both a supine (head of the bed at 0°) and upright (head of bed elevated at 45°) position. The primary outcome of interest was successful intubation of the trachea. Secondary outcomes included log time to intubation, Cormack-Lehane view obtained, Percent of Glottic Opening score, provider assessment of difficulty, and overall provider satisfaction with the position. There were a total of 126 participants: 34 medical students, 84 physician assistant students, and 8 paramedic students. Successful tracheal intubation was achieved in 114 supine attempts (90.5 %) and 123 upright attempts (97.6 %; P = 0.283). Upright positioning was associated with significantly faster log time to intubation, higher likelihood of achieving Grade I Cormack-Lehane view, higher Percent of Glottic Opening score, lower perceived difficulty, and higher provider satisfaction. A subset of 74 participants had no previous intubation training or experience. For these providers, there was a non-significant trend toward improved intubation success with upright positioning vs supine positioning (98.6 % vs. 87.8 %, P = 0.283). For all secondary outcomes in this group, upright positioning significantly outperformed supine positioning.

Targeted temperature management in emergency medicine: current perspectives

Landmark trials in 2002 showed that therapeutic hypothermia (TH) after out-of-hospital cardiac arrest due to ventricular tachycardia or ventricular fibrillation resulted in improved likelihood of good neurologic recovery compared to standard care without TH. Since that time, TH has been frequently instituted in a wide range of cardiac arrest patients regardless of initial heart rhythm. Recent evidence has evaluated how, when, and to what degree TH should be instituted in cardiac arrest victims. We outline early evidence, as well as recent trials, regarding the use of TH or targeted temperature management in these patients. We also provide evidence-based suggestions for the institution of targeted temperature management/TH in a variety of emergency medicine settings.

Heterogeneous properties of central lateral and parafascicular thalamic synapses in the striatum

To understand the principles of operation of the striatum it is critical to elucidate the properties of the main excitatory inputs from cortex and thalamus, as well as their ability to activate the main neurons of the striatum, the medium spiny neurons (MSNs). As the thalamostriatal projection is heterogeneous, we set out to isolate and study the thalamic afferent inputs to MSNs using small localized injections of adeno-associated virus carrying fusion genes for channelrhodopsin-2 and YFP, in either the rostral or caudal regions of the intralaminar thalamic nuclei (i.e. the central lateral or parafascicular nucleus). This enabled optical activation of specific thalamic afferents combined with whole-cell, patch-clamp recordings of MSNs and electrical stimulation of cortical afferents, in adult mice. We found that thalamostriatal synapses differ significantly in their peak amplitude responses, short-term dynamics and expression of ionotropic glutamate receptor subtypes. Our results suggest that central lateral synapses are most efficient in driving MSNs to depolarization, particularly those of the direct pathway, as they exhibit large amplitude responses, short-term facilitation and predominantly express postsynaptic AMPA receptors. In contrast, parafascicular synapses exhibit small amplitude responses, short-term depression and predominantly express postsynaptic NMDA receptors, suggesting a modulatory role, e.g. facilitating Ca(2+)-dependent processes. Indeed, pairing parafascicular, but not central lateral, presynaptic stimulation with action potentials in MSNs, leads to NMDA receptor- and Ca(2+)-dependent long-term depression at these synapses. We conclude that the main excitatory thalamostriatal afferents differ in many of their characteristics and suggest that they each contribute differentially to striatal information processing.