INCIDENCE AND ETIOLOGY OF CARDIAC ARRESTS OCCURRING IN OPERATING AND RECOVERY ROOMS DURING 102,468 ANESTHETICS

This study reviewed retrospectively 186 cardiac arrests (CA) observed in a series of 102,468 anaesthetics, carried out in a University Hospital between 1983 and 1987. Among them 29 were partly or totally related to anaesthesia and 11 had a fatal outcome. On the other hand, 157 CA (144 deaths) were not related to anaesthesia. Mortality rate due to anaesthesia was therefore 1.1 per 10,000. The main causes of anaesthesia related CA were overdosage, with or without hypovolaemia (9 CA, 6 of which occurred under regional anaesthesia); hypoxaemia (6 CA, 5 of which occurred under regional anaesthesia) and multifactorial sudden cardiac arrest (n = 8). The other aetiologies were: myocardial ischaemia (n = 3); anaphylactic shock due to propanidid (n = 1); protamine accident (n = 1); ventricular arrhythmia due to hypokalemia (n = 1). Fourteen CA occurred during induction (2 deaths), 14 during maintenance (8 deaths), and one during recovery. Risk factors for CA included a high ASA class, and the type of anaesthesia: there were 8 CA for 12,981 regional anaesthetics, and 21 for 89,487 general anaesthetics (p = 0.017). Emergency and paediatric anaesthesia were not risk factors. Outcome was independent of ASA class, but was related to aetiology: hypoxaemia (5 out of 6 recovered) and overdose with or without hypovolaemia (7 out of 8 recovered) had favourable outcomes. Furthermore, outcome of CA due to regional anaesthesia was satisfactory (7/8 recovered) (p = 0.08, NS). Such an analysis of the causes of anaesthetic disasters and their rate of occurrence can lead to more effective prevention.