Regimen for accelerated propranolol initial dosing (RAPID)

BACKGROUND: Infantile hemangiomas are common vascular tumors in children. Propranolol has proven effective in treating infantile hemangiomas and while generally safe, has potential risk for more serious side effects of hypoglycemia, hypotension, bradycardia, bronchospasm, and cardiovascular or respiratory compromise. Current prescribing guidelines recommend initiating propranolol doses at 1 mg/kg/day, with up-titration to 2 mg/kg/day. This study aims to compare the incidence of adverse events in infants and children treated with propranolol initiated at 1 mg/kg/day versus being initiated directly at 2 mg/kg/day. METHODS: A retrospective cohort study was conducted using medical records of patients receiving propranolol therapy for infantile hemangiomas between October 2018-March 2021 at the Children's Hospital of Philadelphia. Patients were categorized by initial propranolol dosage: 1 or 2 mg/kg/day. The primary outcome measures included parent-reported adverse events, hypotension (defined by the Pediatric Advanced Life Support criteria), and bradycardia (defined as <1st percentile for age) following propranolol initiation. RESULTS: Out of the 244 patients identified, 123 were initiated at the 1 mg/kg/day dose, and 121 at the 2 mg/kg/day dose. There was no significant difference in the incidence of adverse events between the two groups (p = .057). Additionally, among patients initiated at 2 mg/kg/day, there were no significant differences in the incidence of age-related or weight-related adverse events for those younger than 2 months or those in the 1st or 2nd quartile for weight (p = .53). CONCLUSION: Infants and children initiated at 2 mg/kg/day did not demonstrate an increased incidence of adverse events associated with propranolol compared to those initiated at 1 mg/kg/day. These findings provide clinical evidence for the practice of accelerated propranolol initiation dosing.