Faculty Bibliography

BACKGROUND: While it is certain that some emergency department patients with acute drug overdose suffer adverse cardiovascular events (ACVE), predicting ACVE is difficult. The prognostic utility of the ECG for heterogeneous drug overdose patients remains to be proven. This study was undertaken to validate previously derived features of the initial ECG associated with ACVE in this population. METHODS AND RESULTS: We performed a prospective validation cohort study to evaluate adult emergency department patients with acute drug overdose at 2 urban university hospitals over 5 years in whom an emergency department admission ECG was performed. Exclusion criteria were alternate diagnoses, anaphylaxis, chronic drug toxicity, and missing outcome data. ACVE was defined as any of the following: circulatory shock, myocardial injury, ventricular dysrhythmia, or cardiac arrest. Blinded cardiologists interpreted ECGs for previously derived predictors of ACVE (ectopy, QT prolongation, nonsinus rhythm, ischemia/infarction), QT dispersion, and prominent R wave in lead AVR. Of 589 patients who met inclusion criteria (48% male, mean age 42), there were 95 ACVEs (39 shock, 64 myocardial injury, 26 dysrhythmia, 16 cardiac arrest). The most common drug exposures were as follows: benzodiazepines, opioids, and acetaminophen. Previously derived criteria were highly predictive of ACVE, with QT correction >500 ms as the highest risk feature (OR 11.2, CI 4.6-27). CONCLUSIONS: This study confirms that early ECG evaluation is essential to assess the cardiovascular prognosis and medical clearance of emergency department patients with acute drug overdose. Furthermore, this study validates previously derived high-risk features of the admission ECG to risk stratify for ACVE in this patient population.

CONTEXT: Salicylate poisoning remains a significant public health threat with more than 20,000 exposures reported annually in the United States. OBJECTIVE: We aimed to establish early predictors of severe in-hospital outcomes in Emergency Department patients presenting with acute salicylate poisoning. METHODS: This was a secondary data analysis of adult salicylate overdoses from a prospective cohort study of acute drug overdoses at two urban university teaching hospitals from 2009 to 2013. Patients were included based on confirmed salicylate ingestion and enrolled consecutively. Demographics, clinical parameters, treatment and disposition were collected from the medical record. Severe outcome was defined as a composite occurrence of acidemia (pH <7.3 or bicarbonate <16 mEq/L), hemodialysis, and/or death. RESULTS: Out of 1997 overdoses screened, 48 patients met inclusion/exclusion criteria. Patient characteristics were 43.8% male, median age 32 (range 18-87), mean initial salicylate concentration 28.1 mg/dL (SD 26.6), and 20.8% classified as severe outcome. Univariate analysis indicated that age, respiratory rate, lactate, coma, and the presence of co-ingestions were significantly associated with severe outcome, while initial salicylate concentration alone had no association. However, when adjusted for salicylate concentration, only age (OR 1.13; 95% CI 1.02-1.26) and respiratory rate (OR 1.29; 95% CI 1.02-1.63) were independent predictors. Additionally, lactate showed excellent test characteristics to predict severe outcome, with an optimal cutpoint of 2.25 mmol/L (78% sensitivity, 67% specificity). CONCLUSIONS: In adult Emergency Department patients with acute salicylate poisoning, independent predictors of severe outcome were older age and increased respiratory rate, as well as initial serum lactate, while initial salicylate concentration alone was not predictive.

BACKGROUND: Drug overdose is the leading cause of injury-related fatality in the United States, and respiratory failure remains a major source of morbidity and mortality. OBJECTIVES: We aimed to identify the incidence and risk factors for endotracheal intubation after acute drug overdose. METHODS: This secondary data analysis was performed on a 5-year prospective cohort at two urban tertiary-care hospitals. The present study analyzed adult patients with suspected acute drug overdose to derive independent clinical predictors of endotracheal intubation. RESULTS: We analyzed 2497 patients with acute drug overdose, of whom 87 (3.5%) underwent endotracheal intubation. Independent clinical risk factors for endotracheal intubation were: younger age (odds ratio [OR] 0.97, 95% confidence interval [CI] 0.96-0.98), and history of obstructive lung disease (OR 6.6, 95% CI 3.5-12.3); however, heart failure had no association. Patients with obstructive lung disease had significantly more hypercapnia (mean difference 6.8 mm Hg, 95% CI 2.3-11.3) and a higher degree of acidemia (mean pH difference 0.04, 95% CI 0.01-0.07) than patients without obstructive lung disease. Lack of rapid sequence sedative/paralytic was associated with in-hospital fatality. Early complications of endotracheal intubation itself included desaturation (3.4%) and bradycardia (1%). CONCLUSIONS: Endotracheal intubation was infrequently performed on patients with acute drug overdose, and complications were rare when performed. Risk factors associated with endotracheal intubation included younger age and prior obstructive lung disease.

Background: In comparison to cigarette smoking, little is known about the adverse health consequences of water pipe smoking (WPS). Clinically significant acute carbon monoxide (CO) poisoning is an uncommonly reported adverse effect of WPS. Hypothesis: WPS may be associated with serious adverse effects related to CO poisoning.
Method(s): This is a case series of consecutive patients treated at a large metropolitan hyperbaric oxygen (HBO) treatment referral center associated with a level 1 trauma center and burn unit. The patients either presented primarily to the ED or were referred for evaluation, between March 2015 and September 2015. Each patient smoked a water pipe immediately before the onset of symptoms consistent with CO poisoning, had an elevated COHb documented, and had other environmental sources of CO excluded.
Result(s): Five patients (three males) between the ages of 14 and 50 years were evaluated for CO poisoning afterWPS. Four patients were smoking a water pipe inside their homes, while one patient smoked outdoors. Only two patients smoked cigarettes at least occasionally. On presentation, three patients had also consumed alcohol; all denied any other drug use. Their initial COHb concentration and presenting symptoms were as follows: 11 % (seizure); 21 % (syncope); 22 % (syncope); 24 % (seizure); 25.4 % (syncope and seizure). All patients were hemodynamically stable and all underwent a single HBO treatment at 2.6 ATA. All were asymptomatic and clinically normal after HBO.
Discussion(s): Although this is a large series of carbon monoxide-poisoned patients associated with WPS, it remains unclear why only some users develop an elevated COHb. Additionally, without epidemiological data, the incidence of CO poisoning with WPS is unknown. Furthermore, the relationship between COHb concentrations in the setting ofWPS and the development of symptoms is unclear. Surveillance and research are necessary to better define these relationships.
Conclusion(s): WPS may be an underappreciated source of significant CO poisoning