Über den Einfluss von Operationen mit Herz-Lungen-Maschine auf das postoperative Risiko, ein akutes Nierenversagen zu entwickeln

Background: Acute renal failure after cardiopulmonary bypass operations is a serious complication which is associated with a high morbidity and mortality. The underlying mechanisms of renal injury in these circumstances are poorly understood. It was the aim of this study to evaluate the correlations between parameters of cardiopulmonary bypass surgery and the occurrence of postoperative acute renal failure in a large cohort. Methods: Perioperative information of 3574 patients that underwent open heart surgery in the department of heart- vascular and thoracic surgery at the University of Gottingen between 2000 and 2005 was investigated retrospectively. The associations between postoperative acute renal insufficiency (defined by renal replacement therapy and/or the RIFLE-criteria) and parameters like type of operation, duration of operation, re-operation, type of bypass pump, cross-clamp-time, reperfusion time, hypothermia and blood loss were analysed using different statistical tests within the Statistica® program including like X2 –test, Wilcoxon-mann-whitney-test, kruskal-wallis-test with a significance p-value cutoff of ≤ 0.05. Results: Re-operation, a longer duration of surgery, cross-clamp-time and reperfusion time as well as a higher degree of hypothermia and higher blood loss were significantly associated (p<0.01) with acute renal failure defined as renal replacement therapy as well as according to the RIFLE-criteria. Conclusion: Acute renal failure is a serious complication after open heart surgery. In this study we showed a significant relationship between peri- and intraoperative parameters and the occurrence of acute renal failure in a large cohort. Particularly factors related to ischemia and blood loss play a crucial role in the development of acute renal failure after cardiopulmonary bypass surgery. Further investigations are needed to better understand the underlying mechanisms.