Cerebrovascular accidents developing in the operating theater: a JSA survey for the year 2004

BACKGROUND: The incidence of cerebrovascular accidents (CVA) developing in the operating theater has not been investigated on a large scale. In 2004, the Japanese Society of Anesthesiologists (JSA) started to survey neurological as well as life-threatening events in the operating theater. The incidence of CVA developing in the operating theater was examined using data obtained by the 2004 survey. METHODS: JSA has conducted annual surveys of life-threatening and neurological events in the operating theater by sending and collecting confidential questionnaires to all JSA certified training hospitals. The recovery rate was 91% (874/960 hospitals) in 2004. Seven hundred fourteen hospitals sent valid responses, and 1,218,371 anesthesias were registered. Among these cases, 123 patients were reported to have developed CVA in the operating theater. Incidences according to age class, ASA PS and surgical sites, causes, and their outcome were investigated. The patients with ASA PS 1 or 2 were classified as having good physical status, and those with ASA PS 3-5 were classified as having poor physical status. The causes of events were classified as follows: totally attributable to anesthetic management (AM), mainly to intraoperative pathological events (IP), to preoperative co-morbidity (PC), and to surgical management (SM). RESULTS: Overall incidence of CVA was 1.01/10,000 anesthesias. The incidence in patients aged 66 years or above was 2.00/10,000 anesthesias, which was 3.83-(95% confidential interval 2.57-5.71) fold higher than that in patients aged between 19 and 65 years. The incidences in elective and emergency patients with poor physical status were 3.27 and 7.91/10,000 anesthesias, respectively, which was 7.04- (4.56-10.87) and 17.06-(10.90-26.69) fold higher than that in elective patients with good physical status, respectively. The incidences in patients undergoing thoracotomy combined with laparotomy, craniotomy, or cardiovascular surgery were 2.76, 5.96 and 11.65/10,000 anesthesias, respectively, which were 7.22- (1.64-31.76), 15.59- (8.14-29.86), and 30.52- (16.80-55.44) fold higher than that in patients undergoing laparotomy alone. Among cardiovascular surgery, thoracic aortic surgery showed the highest number of incidents (57.98/10,000 anesthesias), followed by on-pump coronary artery bypass (11.07/10,000 anesthesias). Only one patient undergoing off-pump coronary artery bypass developed CVA, resulting in an 8.14- (1.00-66.18) fold lower incidence of CVA compared to that of on-pump coronary artery bypass. AM, IP, PC and SM were responsible for 4.1%, 24.4%, 27.6% and 35.0% of CVA. The incidence of CVA caused by AM or IP was calculated to be 0.29/ 10,000 anesthesias. If patients undergoing cardiovascular surgery or craniotomy were excluded, the incidence of CVA caused by AM or IP was calculated to be 0.13/ 10,000 anesthesias (15/ 1,134,398 anesthesias). The overall outcome of CVA was as follows: uneventful recovery 9.8%, death within 30 post-operative days 26.0%, vegetative state 6.5%, and sequelae involving deficits in the central nervous system 52.0%. The outcome of CVA caused by AM or IP was as follows: uneventful recovery 20.0%, death within 30 post-operative days 22.9%, vegetative state 8.6%, or sequelae involving deficits in central nervous system 45.7%. Twenty-seven point six percent of reported CVA were considered to have been preventable. CONCLUSIONS: The overall incidence of CVA developing in the operating theater in Japan was reported to be 123 among 1.2 million anesthesias. The incidence was high in elderly patients, in patients with poor physical status, and in patients undergoing cardiovascular surgery. Because the prognosis of CVA developing in the operating theater was poor, clinical strategies for prevention, early detection, prompt diagnosis, and appropriate treatment of CVA should be established.