[The relationship between the yearly number of operations and mortality due to intraoperative critical incidents in patients for cardiac surgery: an analysis of annual survey 2001 conducted by the Japanese Society of Anesthesiologists].
BACKGROUND
The number of surgical operations performed has been reported to have a relation with surgical morbidity and mortality. In Japan, however, the relationship between surgical load and outcome has not been elucidated.


METHODS
We investigated this relationship in patients for cardiac surgery using data from the 2001 annual survey concerning anesthesia-related critical incidents, conducted by the Committee on Operating Room Safety, Japanese Society of Anesthesiologists. Between January 1, 2001 and December 31, 2001, 43,411 patients for cardiac surgery patients were registered from 486 training hospitals certified by the Japanese Society of Anesthesiologists. Intraoperative critical incidents occurred in 632 of the patients. Of these, 289 patients died within 7 postoperative days. The overall mortality was 66.57 per 10,000 anesthetics. Hospitals were divided into 4 groups according to their annual numbers of cardiac operations: Group A, fewer than 50; Group B, 50-99; Group C, 100-199; Group D, more than 200. Mortality rate was expressed as a mean +/- SD (95% confidence interval).


RESULTS
The mortality rates in Group A-D were 107.64 +/- 327.33 (63.47-151.81), 114.42 +/- 168.76 (83.02-145.87), 63.53 +/- 84.35 (48.04-79.01), and 36.97 +/- 52.83 (22.32-51.61) per 10,000 anesthetics, respectively.


CONCLUSIONS
The yearly number of operations has been shown to affect mortality rate due to intraoperative critical incidents among patients for cardiac surgery in Japan. Hospitals with a small number operations should pay significant attention to improving surgical outcome. These results also suggest that centralization or regionalization of cardiac surgery should be discussed from the socio-economical points as well as patient safety.
Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582.
Kazuo
K
Irita
Yasuo
Y
Kawashima
Kiyoshi
K
Morita
Koichi
K
Tsuzaki
Norimasa
N
Seo
Yasuhide
Y
Iwao
Hidefumi
H
Obara
D000758:Anesthesia / Q000401:mortality* / Q000706:statistics & numerical data*; D000776:Anesthesiology; D006348:Cardiac Surgical Procedures / Q000401:mortality* / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications / Q000401:mortality*; D007564:Japan / Q000453:epidemiology; D012955:Societies, Medical; D013997:Time Factors