The Impact of Prostanoids on Pulmonary Gas Exchange During Abdominal Surgery with Mesenteric Traction

We investigated the effect of intravenous (iv) ibuprofen on prostanoid release and on pulmonary gas exchange after abdominal mesenteric traction (MT) during either abdominal aortic surgery or pancreas resection. In a prospective, randomized, double-blind study, 400 mg ibuprofen (pancreas n = 13, aorta n = 13) or a placebo (pancreas n = 13, aorta n = 13) was administered iv before skin incision. MT was applied uniformly. The prostanoid plasma concentrations, venous admixture (Q(va)/Q(t)), and PaO2/FIO2 ratio were determined at baseline (before MT) and 5, 15, 45, and 90 min after MT. Patients who underwent aortic surgery were older and exhibited a lower preoperative PaO2 than those who underwent pancreas resection. Placebo-treated patients revealed a 30-fold peak increase in 6-keto-prostaglandin F1alpha (stable metabolite of prostacyclin) levels after intentional MT during aortic as well as pancreatic operations. This response was accompanied by an increase in Q(va)/Q(t) (ibuprofen: pancreas 7% +/- 1%, aorta 14% +/- 2%; placebo: pancreas 16% +/- 3%, aorta 26% +/- 3%/15 min after MT [mean +/- SEM, P < 0.05, placebo vs ibuprofen]), which resulted in decreased PaO2/ FIO2 ratio only in the aortic surgery patients (ibuprofen: 310 +/- 19; placebo: 237 +/- 24 15 min after MT, [mean +/- SEM, P < 0.05]). The authors conclude that ibuprofen-pretreated patients demonstrated almost constant prostanoid levels without changes in pulmonary gas exchange after MT.