Postoperative Evolution of Inflammatory Response in a Model of Suprarenal Aortic Cross-clamping with and without Hemorrhagic Shock. Systemic and Local Reactions

Surgery of the abdominal aorta generates a systemic inflammatory response (SIR), a source of operative morbidity-mortality. In the present work we attempted to evaluate the evolution of SIR in an experimental model that simulates elective and urgent surgery on the abdominal aorta. Fifteen mini-pigs divided into three groups were used. The animals were subjected to suprarenal aortic/iliac clamping and bypass with a Dacron-collagen prosthetic graft. Groups were as follows: (1) sham (only aortic dissection); (2) clamping and bypass; (3) hemorrhage of 40%, pre-clamping, and bypass. Determinations included (1) tumor necrosis factor-alpha (TNF-α) interleukin (IL)-1β, IL-6, IL-10, interferon-gamma; (2) myeloperoxidase (MPO), superoxide anion (SOA), superoxide dismutase (SOD), and malondialdehyde (MDA); (3) nitrites; (4) iNOS, (5) cell adhesion molecules (ICAM-1, VCAM-1) at 24 hours, 48 hours, and on day 7; and (6) NFκB at 48 hours. Our results point to an increase in all inflammatory variables, corroborated by their molecular regulators such as the expression of CAMs, iNOS, and NFκB. The alterations tended to normalize by day 7, after reperfusion. The results point to the great importance of SIR at all levels (molecular, nuclear, cellular, and systemic) in situations such as elective and urgent abdominal aorta surgery and the role that control of this response could represent for the future of vascular surgery.