Study objective: To report paediatric in-hospital cardiac arrest data according to Utstein style and to determine the effectiveness of cardiopulmonary resuscitation (CPR) in hospitalized children. Design: Retrospective 5-year case series. Setting. Urban, tertiary-care children's hospital. Participants: All patients who sustained cardiopulmonary arrest. Results: Altogether 227 patients experienced a cardiopulmonary arrest during the study period, 109 (48.0%) were declared dead without attempted resuscitation, and CPR was initiated in 118 (52.0%). The incidence of cardiac arrest was 0.7% of all hospital admissions and 5.5% of PICU admissions; the incidence of CPR attempts was 0.4 and 2.5%, respectively. Most of the CPR attempts (64.4%) took place in the PICU and the most frequent aetiology was cardiovascular (71.2%). The 1-year survival rate was 17.8%. Short duration of external CPR was the best prognostic factor associated with survival. With few exceptions, the Paediatric Utstein Style was found to be applicable for reporting retrospective data from in-hospital cardiac arrests in children. Conclusions: In-hospital cardiopulmonary resuscitation was shown to be an uncommon event in children; the survival rate was similar to earlier studies. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.