Analysis of cocaine chronotoxicology in an urban ED

To describe the chronotoxicology of cocaine and its potential impact on emergency department (ED) staffing and services, Drug Abuse Warning Network (DAWN) data from a single urban university ED were retrospectively reviewed. The DAWN data reviewed spanned an 11-year period (1/1/83 through 12/31/93), and 3,762 patients were enrolled. Patients were included if the ED records included documentation of recent cocaine abuse prior to presentation to the ED. Of the 3,762 study patients, 1,609 (43%) had documentation of recent cocaine use: 506 (32%) had used cocaine alone, 614 (38%) had used cocaine and ethanol in combination, and 489 (30%) had used cocaine in combination with other drugs. For all patients using cocaine, there were two significant rhythms (P < .05) identified: a circadian rhythm that peaked at 1800 and a 12-hour rhythm that peaked at approximately noon and midnight. A significant rhythmicity was found among cocaine-using patients who presented during the study period. Increased or shift-adjusted staffing focusing specifically on psychosocial services, detoxification, and security during these peak hours may provide more efficient emergent care for this subpopulation of patients.