Risk Factors Associated with In-hospital Mortality for Patients with Acute Abdomen after Cardiac Surgery

Objectives: Management of an acute abdomen (AA) differs due to the heterogeneity of the underlying pathophysiology. Complications of AA and its overall outcome after cardiac surgery are known to be associated with poor results. The aim of this retrospective analysis was to evaluate risk factors of AA in patients undergoing cardiac surgery.

Methods: Between December 2011 and December 2014, a total of 131 patients with AA after cardiac surgery were identified and retrospectively analyzed using our institutional database. Statistical analysis of risk factors concerning in-hospital mortality of the mentioned patient cohort was performed using IBM SPSS Statistics.

Results: Mean age of the entire patient cohort was 69 ± 11 years with an EuroSCORE II of 7.6 ± 4.0. Out of these patients, n = 34 (25.9%) were treated with IABP or VA-ECMO due to postcardiotomy cardiogenic shock. In case of failure of conservative and endoscopic approaches, a laparotomy was indicated and performed in n = 42 patients (32.1%). Overall in-hospital mortality was 54.2% (n = 71). Analyzing in-hospital nonsurvivors (NS) versus in-hospital survivors (S) peripheral artery disease (28.2 vs. 11.7%; p < 0.05), the use of vasoactive and inotropic substances (19.7% vs. 6.7%; p < 0.05), the need for assist device therapy (33.8 vs. 16.7%; p < 0.05), and the requirement of hemodialysis (67.6 vs. 23.3%; p < 0.01) were significantly higher in the cohort of NS. Furthermore, lactic acid values at the onset of symptoms were shown to be significantly higher in the NS (5.65 ± 5.74 vs. 2.77 ± 2.91 mmol/L; p < 0.01). Assured diagnosis of mesenterial ischemia was strongly associated with worse outcome (40.8% in NS vs. 3.3% in S; p < 0.01).

Conclusion: Diagnostic approach and treatment of AA might be challenging for physicians, especially when dealing with patients after cardiac surgery. High doses of catecholamines, need for supportive hemodynamic assist device systems, and the occurrence of renal failure are risk factors associated with worsen outcome in patients with AA after cardiac surgery. Our data suggest that a rise of lactic acid could potentially be associated with the onset of intestinal malperfusion and should be taken into account in therapeutic decisions preventing fatal mesenterial ischemia.