[The incidence of hypoxia in the immediate postoperative period]

Arterial oxygen saturation (SaO2) was continuously measured using a pulse oximeter in 214 spontaneously breathing adult patients in a recovery room. Hypoxaemia was defined as an SaO2 of 90% or below. The patients were divided into three groups: in group I (n = 83) monitoring was started immediately after arrival in the recovery room, just before oxygen therapy was begun. The patients in group II (n = 106) were observed during and after oxygen therapy. Patients in group III (n = 25), most of whom had regional anaesthesia, were not treated with oxygen in the recovery room. RESULTS. Clinically unexpected hypoxaemia occurred in all three groups: hypoxaemia was observed in 32.6% of patients before oxygen administration (group I). Under oxygen therapy SaO2 was normal in 99.4% of the patients; however, in 30.2% of patients hypoxaemia recurred after oxygen had been discontinued (group II). Hypoxaemic periods were seen in 24% of patients in group III. CONCLUSION. The results indicate the necessity of oxygen administration during transport and in the early postoperative period to all patients. Even during and after regional anaesthesia or brief general anaesthesia, oxygen administration appears to be indicated. Monitoring of SaO2 with a pulse oximeter has become an increasingly standard procedure in modern anaesthesia and should be mandatory.