We report the case of a premature newborn child (36 weeks) who was operated on a teratoma of the sacrum when he was 12 days old and weighed 2,950 g. The patient presented a late postoperative apnea 17 hours after anesthesia. The anesthetic technique consisted of lumbar epidural blockade with 0.33% bupivacaine at a dose of 2.25 ml and superficial inhalation anesthesia with 0.5% isoflurane. Relaxing muscular agents used in this case were succinylcholine (3 mg) for orotracheal intubation and pancuronium bromide (0.3 mg) for maintaining the anesthetic level. The immediate postoperative phase was uneventful but 17 hours after surgery the patient presented apnea, bradycardia (40 beats/min), and marked cyanosis requiring assisted ventilation with bag and mask during 3 min and initial cardiac massage. Recovery of heart rate was immediate and recovery of ventilation was progressive. The patient was treated with caffeine during one week and no relapses occurred. Pneumocardiographic recordings obtained later on revealed sporadic short lasting episodes of apnea (shorter than 15 s) sometimes associated with bradycardia (40 beats/min lower than baseline). There were no apparent intercurrent or precipitating factors for this apnea. We believe that the present clinical picture corresponds to a late postoperative apnea of unknown origin which required reanimation measures and that until present, there are no reported complications of the anesthetic technique that can explain this episode.