How to interpret urine toxicology tests

Emergency Department Drug Surveillance (EDDS) hospital's urinalysis results compared with expanded re-testing by an independent laboratory, a pilot study

INTRODUCTION

Most hospital urine toxicology screens detect a fixed, limited set of common substances. These tests are fast and accurate but may miss emerging trends in substance use in the community and clinical acumen alone is insufficient for identifying new substances.

METHODS

This prospective cohort study examined de-identified urine specimens obtained from patients visiting the Emergency Department (ED) at Prince George's Hospital Center (PGHC), between October 15, 2019 to November 6, 2019 and tested positive for one or more substances. The Emergency Department Drug Surveillance System (EDDS) collects quarterly exports from de-identified electronic health records (EHRs) containing urinalysis results for drug related ED visits. We performed a feasibility study of a new urine specimen submission by collecting a stratified sample of 151 urine specimens from PGHC ED patients. The specimens were tested for 240 drugs using liquid chromatography-tandem mass spectrometry (LC-MS/MS). This paper presents a comparison between the PGHC and expanded testing results.

RESULTS

The expanded urinalysis panel found more cocaine (37% vs. 20%; p < 0.01) and benzodiazepine positives (21% vs. 11%; p < 0.05) than would have been detected by the hospital screen. Additionally, the expanded toxicology panel identified fentanyl in 4-14% of the samples.

CONCLUSION

The EHR data submitted to EDDS from the hospital urine toxicology screen correctly identified hospital substance use patterns over the approximate 1 month study period. The expanded testing also uncovered drugs that the hospital might consider adding to their routine screen. EDDS is a feasible system for monitoring and confirming recent substance use trends among ED patients.

Evaluating the Utility of Toxicologic Analysis in Pediatric Out-of-Hospital Cardiac Arrest

BACKGROUND

The cause of a pediatric out-of-hospital cardiac arrest (OHCA) may go unexplained in the emergency department setting but can be secondary to a toxicologic etiology. It is unclear how toxicologic screens are used in the postarrest period after a pediatric OHCA.

OBJECTIVES

The primary objectives are to describe 1) when the toxicology screen (urine and serum) is used, 2) patient characteristics, and 3) toxicology screen results. We hypothesized that toxicology screens are frequently used but that positive results are uncommon.

METHODS

This was a retrospective study of pediatric OHCA patients admitted to the Penn State Health Children's Hospital pediatric intensive care unit as transfers from the emergency department between January 1, 2011 and May 31, 2018. We reviewed the electronic health record and evaluated for toxicology screen completion, patient characteristics, and toxicology screen results.

RESULTS

One hundred forty-one patients had a pediatric OHCA. Sixty-three (44.7%) patients did not have a toxicology screen completed. A toxicology screen had a higher completion rate for children >11 years of age (n = 26 [78.8%]; p = 0.0024), and in unwitnessed arrests (n = 48 [66.7%]; p = 0.0052). Four cases (5.1%) revealed the presence of substances that were not administered by a medical provider or were illicit.

CONCLUSION

Our study found that in pediatric OHCA, toxicologic screens were completed but were not routinely sent in our institution. There may be factors such as clinician bias or the severity of a patient's illness that impact the approach to toxicologic screening in pediatric OHCA. In addition to the history and physical examination, emergency physician and pediatric intensivists should consider routinely sending toxicologic screens to assist in uncovering any accidental or malicious explanation for the event.