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Open Access Publications from the University of California

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This series is automatically populated with publications deposited by UC San Diego School of Medicine Department of Emergency Medicine researchers in accordance with the University of California’s open access policies. For more information see Open Access Policy Deposits and the UC Publication Management System.

Cover page of Prehospital mass casualty incident triage simulation builds knowledge and confidence in medical trainees.

Prehospital mass casualty incident triage simulation builds knowledge and confidence in medical trainees.

(2024)

BACKGROUND: Mass casualty incident (MCI) triage simulation is an increasingly useful tool for teaching triage systems to medical students, trainees, and hospital staff. MCI simulation in the prehospital setting has not yet been studied in this population. OBJECTIVES/AIMS: We aimed to assess the effectiveness of a prehospital MCI simulation in medical students, residents, and fellows. Our primary outcome was knowledge of the components of the triage algorithms used in MCI response. Our secondary outcome was each participants confidence level if required to assist with or lead a MCI response. METHODS: This was an observational study with pre-post surveys. We recruited 30 medical students, 14 emergency medicine (EM) residents, and four pediatric EM fellows to fill out a survey before and after a 3-h simulation session practicing the START and JumpSTART algorithms on two prehospital MCI scenarios. RESULTS: Overall, all groups demonstrated significant improvement in knowledge of triage colors, information needed to assign a triage color, pediatric airway management during a MCI, and indications for breaths-first CPR. They also demonstrated significant increase in confidence both in assisting with and in leading a MCI response. CONCLUSIONS: Simulated practice triaging patients in prehospital MCI scenarios improves knowledge of triage algorithms and increases confidence in assisting with or leading a MCI response in medical trainees.

Cover page of Lung- and diaphragm-protective strategies in acute respiratory failure: an in silico trial.

Lung- and diaphragm-protective strategies in acute respiratory failure: an in silico trial.

(2024)

BACKGROUND: Lung- and diaphragm-protective (LDP) ventilation may prevent diaphragm atrophy and patient self-inflicted lung injury in acute respiratory failure, but feasibility is uncertain. The objectives of this study were to estimate the proportion of patients achieving LDP targets in different modes of ventilation, and to identify predictors of need for extracorporeal carbon dioxide removal (ECCO2R) to achieve LDP targets. METHODS: An in silico clinical trial was conducted using a previously published mathematical model of patient-ventilator interaction in a simulated patient population (n = 5000) with clinically relevant physiological characteristics. Ventilation and sedation were titrated according to a pre-defined algorithm in pressure support ventilation (PSV) and proportional assist ventilation (PAV+) modes, with or without adjunctive ECCO2R, and using ECCO2R alone (without ventilation or sedation). Random forest modelling was employed to identify patient-level factors associated with achieving targets. RESULTS: After titration, the proportion of patients achieving targets was lower in PAV+ vs. PSV (37% vs. 43%, odds ratio 0.78, 95% CI 0.73-0.85). Adjunctive ECCO2R substantially increased the probability of achieving targets in both PSV and PAV+ (85% vs. 84%). ECCO2R alone without ventilation or sedation achieved LDP targets in 9%. The main determinants of success without ECCO2R were lung compliance, ventilatory ratio, and strong ion difference. In silico trial results corresponded closely with the results obtained in a clinical trial of the LDP titration algorithm (n = 30). CONCLUSIONS: In this in silico trial, many patients required ECCO2R in combination with mechanical ventilation and sedation to achieve LDP targets. ECCO2R increased the probability of achieving LDP targets in patients with intermediate degrees of derangement in elastance and ventilatory ratio.

Cover page of Impact of skilled nursing facility (SNF) 3-day hospitalization requirement waiver during the COVID-19 pandemic on emergency department and inpatient SNF discharges in California.

Impact of skilled nursing facility (SNF) 3-day hospitalization requirement waiver during the COVID-19 pandemic on emergency department and inpatient SNF discharges in California.

(2024)

OBJECTIVE: We sought to study the impact of the Centers for Medicare & Medicaid services (CMS) waiver of the 3-day hospitalization requirement for skilled nursing facility (SNF) care implemented as part of the Federal COVID-19 response on emergency department (ED) and inpatient hospital SNF discharges. METHODS: We conducted a multicenter retrospective cohort study of hospital ED and inpatient visits in California during 18 months before (prewaiver, September 2018-February 2020) and 18 months after (waiver, March 2020-August 2021) waiver implementation. Data were collected from all adult ED and admitted patients utilizing California Department of Health Care Access and Information datasets from all acute care hospitals licensed in the state. Prewaiver and waiver periods were compared for SNF discharge/disposition rates stratified by patient demographic and hospital data with differences in the proportion and 95% confidence interval [CI] reported (SPSS). RESULTS: SNF discharges decreased from the prewaiver to waiver periods from the ED (-7.4% [CI -8.1%, -6.6%]), along with larger declines occurring from the inpatient hospital setting (-18.1% [CI -18.4%, -17.9%]). For Medicare beneficiaries, there was a smaller decrease in ED SNF rates (-3.8% [CI -4.7%, -2.9%]), and there was no significant change for SNF discharge rates for inpatient admissions with a length of stay (LOS) <3 days (+1.0% [CI 0.0%, 2.1%]). CONCLUSION: In California, the CMS waiver did not result in an increase, but an actual decrease rate of SNF discharges from the ED and inpatient setting, though with smaller declines for the ED, Medicare patients, and those with a LOS <3 days.

An Automated System for Physician Trainee Procedure Logging via Electronic Health Records.

(2024)

Importance

Procedural proficiency is a core competency for graduate medical education; however, procedural reporting often relies on manual workflows that are duplicative and generate data whose validity and accuracy are difficult to assess. Failure to accurately gather these data can impede learner progression, delay procedures, and negatively impact patient safety.

Objective

To examine accuracy and procedure logging completeness of a system that extracts procedural data from an electronic health record system and uploads these data securely to an application used by many residency programs for accreditation.

Design, setting, and participants

This quality improvement study of all emergency medicine resident physicians at University of California, San Diego Health was performed from May 23, 2023, to June 25, 2023.

Exposures

Automated system for procedure data extraction and upload to a residency management software application.

Main outcomes and measures

The number of procedures captured by the automated system when running silently compared with manually logged procedures in the same timeframe, as well as accuracy of the data upload.

Results

Forty-seven residents participated in the initial silent assessment of the extraction component of the system. During a 1-year period (May 23, 2022, to May 7, 2023), 4291 procedures were manually logged by residents, compared with 7617 procedures captured by the automated system during the same period, representing a 78% increase. During assessment of the upload component of the system (May 8, 2023, to June 25, 2023), a total of 1353 procedures and patient encounters were evaluated, with the system operating with a sensitivity of 97.4%, specificity of 100%, and overall accuracy of 99.5%.

Conclusions and relevance

In this quality improvement study of emergency medicine resident physicians, an automated system demonstrated that reliance on self-reported procedure logging resulted in significant procedural underreporting compared with the use of data obtained at the point of performance. Additionally, this system afforded a degree of reliability and validity heretofore absent from the usual after-the-fact procedure logging workflows while using a novel application programming interface-based approach. To our knowledge, this system constitutes the first generalizable implementation of an automated solution to a problem that has existed in graduate medical education for decades.

Cover page of Evaluation of bias and gender/racial concordance based on sentiment analysis of narrative evaluations of clinical clerkships using natural language processing

Evaluation of bias and gender/racial concordance based on sentiment analysis of narrative evaluations of clinical clerkships using natural language processing

(2024)

There is increasing interest in understanding potential bias in medical education. We used natural language processing (NLP) to evaluate potential bias in clinical clerkship evaluations. Data from medical evaluations and administrative databases for medical students enrolled in third-year clinical clerkship rotations across two academic years. We collected demographic information of students and faculty evaluators to determine gender/racial concordance (i.e., whether the student and faculty identified with the same demographic). We used a multinomial log-linear model for final clerkship grades, using predictors such as numerical evaluation scores, gender/racial concordance, and sentiment scores of narrative evaluations using the SentimentIntensityAnalyzer tool in Python. 2037 evaluations from 198 students were analyzed. Statistical significance was defined as P < 0.05. Sentiment scores for evaluations did not vary significantly by student gender, race, or ethnicity (P = 0.88, 0.64, and 0.06, respectively). Word choices were similar across faculty and student demographic groups. Modeling showed narrative evaluation sentiment scores were not predictive of an honors grade (odds ratio [OR] 1.23, P = 0.58). Numerical evaluation average (OR 1.45, P < 0.001) and gender concordance between faculty and student (OR 1.32, P = 0.049) were significant predictors of receiving honors. The lack of disparities in narrative text in our study contrasts with prior findings from other institutions. Ongoing efforts include comparative analyses with other institutions to understand what institutional factors may contribute to bias. NLP enables a systematic approach for investigating bias. The insights gained from the lack of association between word choices, sentiment scores, and final grades show potential opportunities to improve feedback processes for students.

Cover page of Tianeptine abuse via novel, extended-release, star-shaped, drug delivery device.

Tianeptine abuse via novel, extended-release, star-shaped, drug delivery device.

(2023)

We report a rare domestic case of exposure to tianeptine and use of a novel, extended-release, six-armed, star-shaped, drug delivery capsule. A 40-year-old male with a history of depression, anxiety, ethanol, opioid, cannabis, and tobacco use disorders presented to the emergency department (ED) from a substance abuse residential recovery treatment program after developing hypertension, tachycardia, and tremor for two day. He used an extended-release, six-armed, star-shaped, drug delivery device he purchased online, filling each arm with 15 mg of tianeptine (90 mg total). His intention was to mitigate the symptoms of kratom/opioid withdrawal through this extended-release method while simultaneously undergoing formal treatment for ethanol withdrawal. Tianeptine is an atypical tricyclic antidepressant that exerts complex mechanisms of action including serotonin (5-HT) neuromodulation as well as full μ-opioid and ∂-opioid receptor agonism. The capsule itself is made of caprolactone, which is a bioabsorbable material similar to absorbable sutures, initially developed as a long-term enteral antimalarial delivery method and is not FDA approved for human use. Over the course of the patients two day hospitalization course he developed symptoms consistent with uncomplicated ethanol withdrawal, which were treated with as-needed phenobarbital. No clinical manifestations of opioid or serotonin toxicity developed. Serial EKGs and telemetry monitoring remained unchanged. The patient was then medically cleared and discharged back to the residential recovery treatment program.

Cover page of Cathepsin B knockout confers significant brain protection in the mouse model of stroke

Cathepsin B knockout confers significant brain protection in the mouse model of stroke

(2023)

Background

Significant advances have been made in our understanding of the endolysosomal cycle. Disruption of this cycle leads to cell death. The objective of this study aims to investigate the role of disrupted endolysosomal cycle in brain ischemia-reperfusion injury.

Methods

A total of 57 mice were randomly assigned into four experimental groups: (i) wildtype (wt) sham control; (ii) wt middle cerebral artery occlusion (MCAO); (iii) cathepsin B (CTSB) knockout (KO) sham control; and (iv) CTSB KO MCAO. Mice were subjected either to 0 min (sham) or 40 min of MCAO, followed by reperfusion for 1 or 7 days. Physical and behavioral examinations were conducted in the 7-day reperfusion group for 7 consecutive days after MCAO. Confocal microscopy was used to assess the levels, redistributions, and co-localizations of key endolysosomal cycle-related proteins. Histopathology was examined by light microscopy.

Results

Confocal microscopy revealed a significant accumulation of CTSB in post-ischemic penumbral neurons relative to those in the sham group. In addition, N-ethylmaleimide sensitive factor ATPase (NSF) was irreversibly depleted in these neurons. Furthermore, CTSB-immunostained structures were enlarged and diffusely distributed in both the cytoplasm and extracellular space, indicating the release of CTSB from post-ischemic neurons. Compared to wt mice, CTSB KO mice showed a significant decrease in hippocampal injury area, a significant increase in the number of survival neurons in the striatal core area, and a significant improvement in physical and functional performance in post-MCAO mice.

Conclusion

Brain ischemia leads to a cascade of events leading to inactivation of NSF, disruption of the endolysosomal cycle, endolysosomal structural buildup and damage, and the release of CTSB, eventually resulting in brain ischemia reperfusion injury. CTSB KO in mice protected the brain from ischemia-reperfusion injury.

Change in grip strength, hang time, and knot tying speed after 24 hours of endurance rock climbing

(2023)

Background: Non-professional climbers are increasingly attempting long routes in a single day. Many suffer injury or rely on search and rescue teams when they become too fatigued to finish. Predicting fatigue is difficult, and existing studies have only studied climbers over durations less than an hour, while many outdoor multipitch climbs require more than an hour of climbing. Objectives: To determine how strength, endurance, and dexterity reflect fatigue after 24 h of continuous climbing. Methods: Volunteer competitors completed measurements of grip strength, static hang time to failure, and time to tie a figure-eight follow-through knot. Measurements were taken during the registration period before the competition and again within an hour after the competition ended. Measurements were compared using the paired t-test. Subgroup analysis was applied to competitors by division. Linear regression was applied to determine the relationship between vertical feet climbed and the number of routes climbed during the competition on each metric. Results: Thirty-six total climbers (average age 29.4 years old) completed pre- and post-competition measurements. After 24 h of climbing (n = 36), mean grip strength decreased by 14.3–15 lbs or 14.7%–15.1% (p < 0.001) and static hang time decreased by 54.2 s or 71.2% (p < 0.001). There was no significant change in time to tie a figure-eight-follow-through knot. Grip strength and hang time decreases were significant in climbers with outdoor redpoints of 5.10a and above. Hang time decreased by 5.4 s per 1,000 vertical feet climbed (p = 0.044). Conclusion: Climbers can expect to experience a 14.7%–15.1% decrease in grip strength and 71.2% decrease in static hang time after 24 h of continuous climbing. These changes may make it difficult to climb consistently over a long objective, and climbers can use these measures at home to train for longer climbing routes. Future studies on shorter climbing intervals can help determine rates of decline in performance measures.

Cover page of A Review of Bicarbonate Use in Common Clinical Scenarios

A Review of Bicarbonate Use in Common Clinical Scenarios

(2023)

Background

The use of sodium bicarbonate to treat metabolic acidosis is intuitive, yet data suggest that not all patients benefit from this therapy.

Objective

In this narrative review, we describe the physiology behind commonly encountered nontoxicologic causes of metabolic acidosis, highlight potential harm from the indiscriminate administration of sodium bicarbonate in certain scenarios, and provide evidence-based recommendations to assist emergency physicians in the rational use of sodium bicarbonate.

Discussion

Sodium bicarbonate can be administered as a hypertonic push, as a resuscitation fluid, or as an infusion. Lactic acidosis and cardiac arrest are two common scenarios where there is limited benefit to routine use of sodium bicarbonate, although certain circumstances, such as patients with concomitant acute kidney injury and lactic acidosis may benefit from sodium bicarbonate. Patients with cardiac arrest secondary to sodium channel blockade or hyperkalemia also benefit from sodium bicarbonate therapy. Recent data suggest that the use of sodium bicarbonate in diabetic ketoacidosis does not confer improved patient outcomes and may cause harm in pediatric patients. Available evidence suggests that alkalinization of urine in rhabdomyolysis does not improve patient-centered outcomes. Finally, patients with a nongap acidosis benefit from sodium bicarbonate supplementation.

Conclusions

Empiric use of sodium bicarbonate in patients with nontoxicologic causes of metabolic acidosis is not warranted and likely does not improve patient-centered outcomes, except in select scenarios. Emergency physicians should reserve use of this medication to conditions with clear benefit to patients.