Objective: To determine the relationship of demographic and clinical variables to cost, to revenue based on diagnosis-related groups, and to profit in patients in a pediatric intensive core unit (PICU). Design: Prospective collection of clinical and demographic data of patients sampled. Detailed financial data for all patients discharged from the hospital were compiled by the office of financial planning. A combined data set was used for analysis. Setting: A mulildisciplinary PICU within a general, tertiary-care, teaching hospital in on urban environment. Patients: Consecutive sample of 1174 pediatric patients discharged from the PICU during a 24-month period. Measurements and main results: Hospital cost (not charges) determined according to industry standards. Revenue was determined by the DRG system. Of the 1174 cases identified, DRG coding and financial data were 97% complete. The mean loss (negative profit) per patient was $9218 +/- $33,676. Profit was significantly and adversely affected by outlier status, death, high risk of death, interhospital transfer, emergency admission, young age, and mechanical ventilation. Multivariate analysis revealed that duration of stay, death, interhospital transfer, oad age negatively correlated with profit. Conclusion: Under a DRG-based reimbursement system, the operation of an active PICU with a broad referral bose may not be desirable from a financial perspective. Similar studies at other institutions could help establish a data base with which the DRG system con be refined.