1208: Safety of Chlorpromazine for Treating Delirium in Patients Recovering From Pediatric Cardiac Surgery

Introduction: Delirium is a common problem for pediatric patients recovering from cardiac surgery and has been associated with worse outcomes. Data describing intravenous (IV) pharmacologic management of delirium in this patient population are limited. We aim to report our off-label use of IV chlorpromazine to treat hyperactive delirium in infants following cardiac surgery. We hypothesized that chlorpromazine is safe for treating in delirium pediatric patients recovering from cardiac surgery. Methods: We conducted a single-center retrospective cohort study of patients less than 365 days old who underwent cardiac surgery in 2024 and received IV chlorpromazine for delirium within 7 days of their index surgery. Hemodynamic data 1 hour before and 4 hours after chlorpromazine doses and Cornell Assessment of Delirium (CAPD) scores obtained within 12 hours before and after chlorpromazine doses are reported as mean ± standard deviation and compared using paired t-tests. Results: We reviewed 30 patients who received 59 doses of chlorpromazine – median 1 dose per patient (25%,75%:1,10) and median dose 0.11 mg/kg (25%,75%:0.05,0.21). Median age at surgery was 193 days (25%,75%:21,334) and median weight was 6.8 kg (25%,75%:4.1,10.2). The most common procedures were ventricular septal defect repair (n=10), superior cavopulmonary anastomosis (n=5), Tetralogy of Fallot repair (n=4), and atrioventricular canal repair (n=3). More than half (n=33, 56%) of chlorpromazine doses were administered within 48 hours of surgery. Systolic blood pressure (94.8 ± 15.9 mmHg vs 90.9 ± 15.0 mmHg, p=0.09) and heart rate (128.1 ± 20.4 beats/min vs 127.8 ± 20.1 beats/min, p=0.88) were not statistically different before and after chlorpromazine doses, while vasoactive-inotropic score significantly decreased after chlorpromazine (3.4 ± 2.8 vs 3.2 ± 2.9, p=0.049). Additionally, CAPD scores, available for 22 doses, were significantly decreased after chlorpromazine (15.3 ± 4.2 vs 11.2 ± 5.8, p=0.005). No patients experienced new arrhythmias, seizures, or extrapyramidal symptoms following chlorpromazine exposure, and all survived to hospital discharge. Conclusions: Chlorpromazine may be a safe intravenous pharmacologic option for managing delirium in infants recovering from cardiac surgery. Larger studies to assess safety and efficacy are needed.