We report the intensive care management of 23 children (age 3-15 years) following orthotopic heart (HT) and combined heart and lung transplantation (HLT) performed at our 2 institutes between February 1985 and August 1989. Cyclosporin A, azathioprine and steroids were given as routine immunosuppression, whilst anti-thymocyte globulin (ATG) was used for the first 3 post-operative days. Mean ventilation time was 24.6 h (range 4-74 h). Cardiovascular support comprised isoprenaline infusions in all patients (mean period 65.7 h) whilst dopamine and other inotropic agents were used less frequently. Sequential atrioventricular pacing was required more often in the HT patients (n = 9) than in the HLT patients (n = 4). Fluid input was restricted to maintain a plasma osmolality of 290-300 mosm/kg. There were 2 perioperative deaths both due to acute right heart failure. Other post-operative complications included: bleeding (n = 3); acute graft rejection (n = 4); infection (n = 3); systemic hypertension (n = 6); neurological abnormalities (n = 2); renal dysfunction (n = 6) and hyperglycaemia (n = 6).