Intestinal ischaemia following cardiac surgery: a multivariate risk model

Objective: Intestinal ischaemia following cardiac surgery is a serious complication, which carries a high mortality rate. Several studies have examined pre-operative and intra-operative risk factors. We aimed to develop a multivariate risk model to identify those patients at highest risk of intestinal ischaemia. Methods: Data was prospectively collected for 10,976 consecutive cardiac surgery patients from our institution between April 1997 and March 2004. Fifty (0.5%) patients developed post-operative intestinal ischaemia. A forward stepwise multivariate logistic regression analysis was undertaken to identify predictors of developing intestinal ischaemia. Intra-operative and post-operative variables were censored at the time of onset of intestinal ischaemia. Results: The predictors of post-operative intestinal ischaernia were: post-op inotrope and dialysis support (OR 6.7; p < 0.001), post-op ventilation > 48 h (OR 5.1; p < 0.001), age at operation (OR 1.06 [for each additional year]; p < 0.001), post-op atrial. fibrillation (OR 2.3; p, = 0.014) and blood loss in intensive care unit (ICU) > 700 ml (OR 2.0; p = 0.037). The predictive ability of this model was very good with an area under the receiver operating characteristic curve of 0.93. In-hospital mortality for the patients who developed intestinal ischaernia was 94% (47/50) compared to 3.6% (390/10,926) for the other patients (p < 0.001). Conclusions: Although the incidence of intestinal ischaemia following cardiac surgery is low, the prognosis for these patients is very poor. We have identified several risk factors, and developed a muttivariate prediction tool., which may be useful in identifying patients at high-risk of developing intestinal ischaernia. (c) 2006 Elsevier B.V. All rights reserved.