High frequency oscillatory ventilation (HFOV) is one of the artificial ventilation techniques used for the treatment of severe respiratory distress in the neonatal period. We studied (between 1987 and 1992) 57 newborn infants ventilated by HFOV during surgery. The aim was to facilitate the surgical procedure without having any deleterious effects on the gas exchange or the hemodynamic state of the infant. Three groups were studied. Group I (thoracic procedures: oesophageal atresia and pulmonary malformations, n = 25), group II (diaphragmatic hernia, n = 22), group III (abdominal procedures, n = 10). In the thoracic surgery group, no deleterious effect related to the HFOV was reported. The hyperventilation noticed after anaesthetic induction was rapidly corrected by placing the patient in a lateral position. In the three groups, no intraoperative complications related to the HFOV were observed. The diaphragmatic hernia group was divided into two subgroups according to the timing of surgery (emergency surgery, surgery after stabilization). In the latter subgroup, surgery was performed when the ventilation and gas exchange conditions had significantly improved. This subgroup showed the highest survival rate. This technique of peroperative ventilation is specifically used in the thoracic and diaphragmatic procedures of term and preterm newborn infants. It achieves a more stable operative field with less pulmonary expansions and diaphragmatic movements. In spite of the fact that HFOV is seldom used during anaesthesia, this study confirms its safety as well as the simplicity of its monitoring.