Hypoxaemia during recovery from anaesthesia—an audit of children after general anaesthesia for routine elective surgery

Summary Arterial oxygen saturation was measured by pulse oximetry in 105 children (aged 2 weeks-14 years) during recovery from general anaesthesia. Oxygen saturation was monitored continuously from the time that anaesthesia ended in the operating theatre until the children were fit to leave the recovery ward. All children breathed room air during transfer to the recovery area; 81 children continued to breathe room air in the recovery ward while the remainder received supplementary oxygen. Fifty-six children became significantly hypoxaemic (oxygen saturation < 90%) at some stage. Hypoxaemia occurred most frequently after termination of anaesthesia (immediate postoperative period) and then later in the recovery ward when the children began to wake up (post-waking period). The administration of 100% oxygen at the end of anaesthesia had no effect on the incidence of early hypoxaemia which was greatest in children whose trachea had been intubated. Late hypoxaemia was associated most commonly with crying and breath-holding and was reduced significantly by supplemental oxygen. The oxygen saturation of children on return to the ward was significantly lower than the pre-operative value (p < 0.001).