Optimization of Pharmacist Medication Management and Mortality in the Intensive Care Unit.

Abstract

Background: Medication-related morbidity due to inappropriate prescribing, delays in appropriate treatment, and adverse drug events contributes to ICU patient mortality. Comprehensive medication management (CMM) is a care standard provided by pharmacists in collaboration with the interprofessional team. Optimizing ICU pharmacist workload via the pharmacist-to-patient ratio while ensuring daily CMM may reduce mortality.

Research question: Is ICU pharmacist staffing, measured by the pharmacist-to-patient ratio and absence of CMM, associated with in-hospital mortality among critically ill adults?

Study design and methods: Adults admitted to an ICU from 64 centers (in the United States, Jordan, and Saudi Arabia) were enrolled in a multicenter observational study that collected patient and team staffing data from August 2023-January 2025. The primary outcome was in-hospital mortality. The primary exposure was the pharmacist-to-patient ratio calculated per patient, averaged over the ICU stay. A secondary exposure was the absence of CMM for at least 1 day of the ICU stay. Multivariable generalized estimating equations (GEE) were used to estimate associations with in-hospital mortality, accounting for clustering by center and adjusting for patient-, ICU-, and hospital-level covariates.

Results: Among 28,795 patients enrolled, the median (IQR) pharmacist-to-patient ratio was 1:17 (13-23). Each one-patient increase in the pharmacist-to-patient ratio was associated with a 1% increase in the odds of in-hospital mortality (Odds Ratio [OR] 1.01, 95% Confidence Interval [CI] 1.00-1.01, p=0.04). Patients who did not receive pharmacist-delivered CMM for at least 1 day of the ICU stay had 20% higher odds of in-hospital mortality (OR 1.20, 95% CI 1.03-1.40, p=0.02). Patients cared for at a pharmacist-to-patient ratio of 1:15.1-46 had 10% higher odds of mortality compared to those cared for at a ratio of 1:7-15 (OR 1.10, 95% CI 1.00-1.22).

Interpretation: Increasing pharmacist-to-patient ratios and the absence of pharmacist CMM every day were both associated with increased in-hospital mortality.