Although a number of studies have described endotracheal intubation of adult patients in the prehospital setting, there are few studies on prehospital endotracheal intubation of pediatric patients. The purposes of our study were to determine how frequently prehospital endotracheal intubation was used in pediatric cardiopulmonary arrests when a paramedic trained in endotracheal intubation was present, to determine the success rate and complications associated with the procedure in the field, and to compare resuscitation rates and outcome in patients with and without prehospital endotracheal intubation. Our retrospective study covered a 38-month period and included all prehospital victims of medical cardiopulmonary arrest under the age of 19 years. Data were collected from field assessment forms and validated by hospital charts, autopsy reports, coroner's reports, death certificates, and emergency medical services central dispatch logs. Of 63 victims of medical cardiorespiratory arrest, 42 had intubating paramedics present at the scene. Twenty-eight of 42 patients (66%) had endotracheal intubation attempted. Eighteen of 28 attempts (64%) were successful, associated with a major complication rate of 7% (two of 28) and a minor complication rate of 39% (11 of 28). In patients less than 1 year old, only six of 16 (38%) had endotracheal intubation attempted and only three of six (50%) attempts were successful. Of the 18 patients who were intubated successfully before arrival at the hospital, nine (50%) survived to hospital admission and one (6%) survived to discharge. The remainder died in the emergency department.(ABSTRACT TRUNCATED AT 250 WORDS)