Impact of Extended-Hours Emergency Department Pharmacy Service on Hospital Length of Stay for High-Needs Patients

Objective: To evaluate the effect of an extended-hours emergency department (ED) clinical pharmacy service (8am–9pm, seven days a week) on hospital length of stay (LOS) for high medication needs (high-needs) general medicine unit (GMU) patients. Methods: This retrospective cohort study was conducted across three EDs within the same health network from March to September 2022. The study compared high-needs GMU patients who were provided a best possible medication history (BPMH) by an ED pharmacist (ED-BPMH) versus BPMH completed on the ward by a GMU inpatient ward pharmacist (GMU-BPMH). Primary outcome was inpatient LOS. Secondary outcomes included ED and total LOS. Data collected included patient demographics (age, sex), home medications, discharge disposition and Charlson Comorbidity Index (CCI), derived from ICD-10 coded records. Results: Analysis of 3,277 patients (1,597 ED-BPMH, 1,680 GMU-BPMH) revealed balanced groups with respect to age, CCI and number of home medications with a median of 83.3 vs 83.2 years; 4.0 vs 4.0; 10.0 vs 10.0, respectively. However, the GMU-BPMH group contained a higher proportion of male sex (48.4% vs. 45.1%). After adjustment for confounders, the estimated median difference for LOS was -0.71 days (-17.0 hours) lower in the ED-BPMH group (95% CI: -1.10, -0.32; p