The effect of ibuprofen on cardiac performance during abdominal aortic cross-clamping

The use of an aortoiliac side-arm conduit to maintain distal perfusion during thoracoabdominal aortic aneurysm repair

Thoracoabdominal aneurysm repair continues to be associated with a significant risk of operative complications, many of which are related to the prolonged period of aortic cross clamping inherent in the procedure. A variety of adjuvant techniques have been used in attempts to decrease morbidity, including atriofemoral extracorporal bypass, subarachnoid drainage, epidural cooling, and preliminary axillofemoral bypass. Herein is described a method to maintain distal perfusion with a side-arm conduit, originating from the most proximal aspect of the aortic graft and terminating on the left iliac artery. The technique has the potential to minimize hemodynamic instability while decreasing the period of pelvic and lower extremity ischemia and simplifying reattachment of aortic branch vessels. This method provides another option that can be considered in these technically demanding operative procedures.

Does a postimplantation syndrome following endovascular treatment of aortic aneurysms exist?

The postimplantation syndrome (PIS) is a weakly defined condition that has been observed following endovascular treatment of aortic aneurysms; the postulated criteria include significant leukocytosis, fever, and/or coagulation disturbances. Among the factors that are supposed to contribute to this syndrome are contact activation by the stent covering with consecutive endothelial activation. Associated clinical parameters of a PIS were perioperatively monitored in the postoperative phase in a total of 69 patients with infrarenal aortic aneurysms treated with Y-stent grafts. C-reactive protein (CRP)-levels, leukocyte concentrations, and body temperature curves were directly compared to those of 50 patients undergoing conventional transperitoneal aneurysm resection. A subgroup of 10 patients of the endovascular group was compared with 13 operated-on patients with regard to an ischemia-reperfusion syndrome of the lower extremities. The mediator determinations were performed on venous (femoral vein) as well as in systemic (arterial) blood samples. The incidence of temperature values above 38 degrees C was higher in patients following endovascular treatment (72%) compared to conventionally operated-on patients (28%). CRP levels were not significantly different within the first 8 post-operative days. During open surgery, significantly higher values for lactate and lower pH levels were observed (p<0.01), as well as higher 6 keto prostaglandin F1alpha (PGF1alpha) levels. There was a short peak of PGF1alpha during eventeration of the intestine during the operative procedure that could not be detected during endovascular manipulations. The clinical and biochemical parameters do not prove the presence of a PIS following endovascular treatment of aortic aneurysms. In contrast, during open surgery the unspecific inflammatory reaction is higher, but not long-lasting. In the future, the suggested phenomenon of a decreased antiinflammatory cytokine response during endovascular surgery needs to be further examined.

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.

The effects of ibuprofen on the physiology and survival of patients with sepsis. The Ibuprofen in Sepsis Study Group

BACKGROUND

In patients with sepsis the production of arachidonic acid metabolites by cyclooxygenase increases, but the pathophysiologic role of these prostaglandins is unclear. In animal models, inhibition of cyclooxygenase by treatment with ibuprofen before the onset of sepsis reduces physiologic abnormalities and improves survival. In pilot studies of patients with sepsis, treatment with ibuprofen led to improvements in gas exchange and airway mechanics.

METHODS

From October 1989 to March 1995, we conducted a randomized, double-blind, placebo-controlled trial of intravenous ibuprofen (10 mg per kilogram of body weight [maximal dose, 800 mg], given every six hours for eight doses) in 455 patients who had sepsis, defined as fever, tachycardia, tachypnea, and acute failure of at least one organ system.

RESULTS

In the ibuprofen group, but not the placebo group, there were significant declines in urinary levels of prostacyclin and thromboxane, temperature, heart rate, oxygen consumption, and lactic acidosis. With ibuprofen therapy there was no increased incidence of renal dysfunction, gastrointestinal bleeding, or other adverse events. However, treatment with ibuprofen did not reduce the incidence or duration of shock or the acute respiratory distress syndrome and did not significantly improve the rate of survival at 30 days (mortality, 37 percent with ibuprofen vs 40 percent with placebo).

CONCLUSIONS

In patients with sepsis, treatment with ibuprofen reduces levels of prostacyclin and thromboxane and decreases fever, tachycardia, oxygen consumption, and lactic acidosis, but it does not prevent the development of shock or the acute respiratory distress syndrome and does not improve survival.