European Journal of Cardio-Thoracic Surgery, Vol 11, 1141-1145, Copyright © 1997 by European Association for Cardio-thoracic Surgery
Cardio-pulmonary-bypass time has important independent influence on mortality and morbidity
RM Wesselink, A de Boer, WJ Morshuis and JA Leusink
Anaesthesiology and Intensive Care, St. Antonius Hospital, EM Nieuwegein, Netherlands. rmj.wesman@inter.nl.net
OBJECTIVE: To determine the influence of cardio-pulmonary-bypass-time on
hospital mortality and ICU-morbidity in isolated CABG surgery. METHODS:
Between 1985 and 1994 perioperative data of 8578 consecutive CABG
operations were prospectively collected. Seven variables: gender, redo vs.
primary operation, elective vs. urgent surgery, age in 4 categories, use of
IMA, number of distal anastomoses (> 4 vs. < = 4), and
cardio-pulmonary-bypass-time in four categories were entered in
multivariate logistic regression analysis and odds ratios for respective
cardio-pulmonary-bypass-time-categories with regard to mortality,
length-of-stay in the ICU and 8 ICU-complications were calculated.
Bypass-time up to 90 min was the reference category, the other categories
were from 1.5 to 2.5 h, 2.5 to 3.5 h, and longer than 3.5 h. RESULTS: 8337
operations had complete data. Mortality and ICU- morbidity were low. The
odds ratios for mortality were 2.3 (P = 0.0094), 7.4 (P < 0.0001) and
20.7 (P < 0.0001) for ascending bypass- time-categories. The odds ratios
for prolonged ICU-stay were 1.8 (P = 0.0002), 3.3 (P < 0.0001) and 7.9
(P < 0.0001) for ascending bypass- time-categories. For postoperative
complications the same pattern was found: consequently higher odds ratios
for longer bypass-time- categories. CONCLUSION: The highly significant
correlation between cardio-pulmonary-bypass-time-category and the
occurrence of undesirable postoperative events is demonstrated by the
consequent rise in odds ratios. This independent influence of
cardio-pulmonary-bypass-time on outcome reflects both problems encountered
during revascularisation and time-related influence of
cardio-pulmonary-bypass on the human body. When a predictive model was
created, CPBT proved to be a good predictor of undesirable postoperative
events.
