Postoperative Apnea, Bradycardia, and Oxygen Desaturation in Formerly Premature Infants

Eighteen formerly premature infants scheduled for inguinal herniorrhaphy and who were less than 51 wk postconceptional age were assigned to either the general anesthesia group (GA: atropine, halothane, and nitrous oxide) or the spinal anesthesia group (SA: hyperbaric tetracaine). Twelve-hour, three-channel continuous recordings of respiratory rate (chest wall impedance), electrocardiogram (ECG), and hemoglobin O2 saturation (SpO2) were obtained preoperatively and after surgery. These were analyzed for short (11-15s) and long (> 15 s) apnea spells, periodic breathing, and episodes of hemoglobin oxygen desaturation and bradycardia. Infants in the GA group had lower postoperative minimum SpO2 (68.7% +/- 11.4%) and minimum heart rate (79 bpm +/- 19) than infants in the SA group (80.7% +/- 9.2%, and 109 bpm +/- 30, respectively; P < 0.05) and had lower postoperative minimum SpO2 and minimum heart rate than they had preoperatively (79.0% +/- 13.7%, and 93 bpm +/- 31, respectively; P < 0.05); pre- and postoperative studies in the SA group did not differ. There were no differences in the incidence of postoperative central apnea. We conclude that spinal anesthesia reduces postoperative hemoglobin oxygen desaturation and bradycardia in formerly premature infants undergoing inguinal herniorrhaphy.