BACKGROUND: Pediatric cardiac care is costly and requires extensive resources. We studied the effect of clinical pathways on practice patterns and patient care outcomes in infants and children hospitalized for cardiac surgery. METHODS: In consecutive patients admitted for selected cardiac surgical procedures before (n = 69) and after (n = 173) implementation of clinical pathways, outcomes including hospital length of stay, days in the ICU, time to extubation, ordering of blood studies, costs, and readmissions were compared. Data were analyzed for each of five cardiac surgical procedures: repair of an atrial septal defect, repair of a ventricular septal defect, division of a patent ductus arteriosus, repair of tetralogy of Fallot, and neonatal arterial switch operation to correct transposition of the great arteries. RESULTS: A significant reduction in length of hospital stay, including days in the ICU (decreased 1 to 2 days per admission), was achieved after the clinical pathway was implemented. Reductions in average duration of mechanical ventilation ranged from 28% for repair of a ventricular septal defect to 63% for repair of tetralogy of Fallot. The number of blood studies ordered decreased 20% to 30%. A significant reduction in hospital costs for each procedure, ranging from 16% to 29%, was also achieved with no adverse effects on patients' outcomes. CONCLUSIONS: Use of clinical pathways with children hospitalized for cardiac surgery can shorten length of stay in the hospital, reduce use of resources, and improve cost-effectiveness with beneficial outcomes for patients.