When Is Laparotomy for Mesenteric Ischemia After Aortic Dissection Futile?

BACKGROUND Tissue necrosis from persistent mesenteric ischemia after aortic dissection may progress to sepsis and death without emergency laparotomy. However, the signs of mesenteric necrosis are common in patients experiencing nonsurvivable multisystem failure after aortic catastrophe. This study examined when and whether laparotomy offers a chance for meaningful survival in these patients.<br /> METHODS A total of 145 patients treated for acute type A or type B aortic dissection with mesenteric ischemia were identified from a single institution from 2006 to 2022. Of those patients, 29 underwent laparotomy, all for compelling clinical indications. Detailed clinical characteristics were studied with respect to short- and long-term outcomes in these patients.<br /> RESULTS Among the patients who underwent laparotomy, 45% (13 of 29) survived to discharge compared with 71% (103 of 145) of all patients with mesenteric malperfusion. Serum lactate and arterial pH were both very strongly associated with survival after laparotomy. Among survivors and nonsurvivors, the mean lactate level before laparotomy was 6.3 mmol/L vs 13.4 mmol/L (P 1 / 4 .024), and the mean pH was 7.39 vs 7.20 (P < .001). In particular, a lactate value higher than 8 mmol/L (odd ratio, 16.5; 95% CI, 2.0-192; P = .003) and a pH lower than 7.30 (odds ratio, 14.4; 95% CI, 1.87-128; P = .003) were highly predictive of mortality. Survival to discharge after laparotomy for patients with both severe lactatemia and severe acidosis (defined earlier) was 9% (1 of 11) compared with 90% (9 of 10) for patients with neither severe lactatemia nor acidosis.<br /> CONCLUSIONS The degree of lactic acidosis can effectively identify patients for whom laparotomy is futile and those for whom it is not after aortic dissection with mesenteric ischemia.