Elevated levels of soluble tumor necrosis factor receptors are associated with increased mortality rates in patients who undergo operation for ruptured abdominal aortic aneurysm

Abstract

Purpose: Elevated levels of soluble tumor necrosis factor receptors (sTNF-Rs) are associated with multiple organ failure and increased mortality rates in critically ill patients. Paradoxically, experimental data suggest exogenous sTNF-Rs may improve outcome in patients who undergo elective abdominal aortic aneurysm (AAA) repair. This study examines, for the first time, changes in sTNF-R levels during repair of ruptured and nonruptured AAA. Methods: Sixteen patients who underwent surgical procedures for ruptured AAA and 10 patients who underwent surgical procedures for nonruptured AAA were studied. Levels of sTNF-Rs p55 and p75 were measured before the operation and immediately before and 5 minutes, 6 hours, and 24 hours after aortic clamp release. Results: When compared with nonruptured AAA, levels of sTNF-R p55 were significantly higher in ruptured AAA 5 minutes (P < .02) and 24 hours after aortic clamp release (P < .05). Levels of sTNF-R p75 were significantly higher in ruptured AAA before (P < .05), during (P < .001), and after the surgical procedure (P < .01). Six hours after aortic clamp release, sTNF-R p75 levels were significantly higher in nonsurvivors of ruptured AAA when compared with survivors (P < .05) and patients who underwent surgical procedures for nonruptured AAA (P < .01). Conclusion: Ruptured AAA repair is associated with increased sTNF-R expression. Furthermore, elevated levels of sTNF-R p75 are associated with increased postoperative mortality rates.