[Postoperative apnea--a special risk for former preterm infants]

Infants who had been originally preterm are subject to a particularly high risk after surgical interventions involving anaesthesia, due to a tendency to experience disturbance of respiratory regulation. Of a total of 130 originally preterm infants who had to undergo anaesthesia for so-called minor surgery, respiratory anomalies were seen in 66%, 48%, 10% and 7% of the infants in the age groups of 40, 50, 60 and 80 weeks after conception, respectively. Therapeutic measures were necessary only in patients up to a post-conceptional age of 40 to 50 weeks, the respective incidences being 24% and 20%. To minimise the risk of postoperative early and late apnea in ex-preterm infants, the following measures are presented and discussed: elective surgical interventions should be postponed until after the 50th post-conceptional week; in individual cases, indication for perioperative theophylline/caffeine treatment can be made more precise by means of preoperative ECG-coupled impedance pneumography; all measures of preoperative preparation, choice of anaesthetics and of adjuvant drugs, as well as perioperative infusion therapy, must be taken in full consideration of all neonatal previous diseases; patients up to the 50th week after conception require intensive-care monitoring primary and post-anaesthesiologically for at least 24 hours. In all patients who were older than 50 week after conception, two hours of intensive-care monitoring in the so-called "recovery from anaesthesia room" followed by 12 hours of ECG and apnea monitoring proved sufficient; in ex-preterm infants, even minor surgery should be performed on an in-patient basis only, to ensure proper monitoring.