A randomized multicenter study of remifentanil compared with halothane in neonates and infants undergoing pyloromyotomy. II. Perioperative breathing patterns in neonates and infants with pyloric stenosis

Although former preterm birth infants are at risk for postoperative after s urgery, it is unclear whether the same is true of full-term birth infants. We evaluated the incidence of apnea. in 60 full-term neonates and infants u ndergoing pyloromyotomy both before and after anesthesia. All subjects were randomized to a remifentanil- or halothane-based anesthetic. Apnea was def ined by the presence of prolonged apnea (> 15 s) or frequent brief apnea, a s observed on the pneumocardiogram. Apnea occurred before surgery in 27% of subjects and after surgery in 16% of subjects, with no significant differe nce between subjects randomized to remifentanil or halothane anesthesia. Th is apnea was primarily central in origin, occurred throughout the recording epochs, and was associated with severe desaturation in some instances. Of the subjects with normal preoperative pneumocardiograms, new onset postoper ative apnea occurred in 3 (23%) of 13 subjects who received halothane-based anesthetics versus 0 (0%) of 22 subjects who received remifentanil-based a nesthetics (P = 0.04). Thus, postoperative apnea can follow anesthesia in o therwise healthy full-term infants after pyloromyotomy and is occasionally severe with desaturation. New-onset postoperative apnea was not seen with a remifentanil-based anesthetic.