Traumatic perforation of duodenal diverticulum.

A fragile 72-year-old female with previous coronary artery disease sustained blunt abdominal trauma in a motor vehicle crash. A ruptured duodenum was identified by computed tomography scanning. Exploratory laparotomy revealed that the duodenal rupture was caused by perforation of a diverticulum in the second portion of the duodenum. The surgical management of the injury to the duodenum is described in detail.

Stapler technique for extrahepatic vascular control during hepatic resection.

A technique is described for extrahepatic division of the hepatic veins and portal structures to be resected utilizing a vascular stapler. The authors have employed this technique in more than 200 consecutive cases of hepatic resection. No major hepatic venous bleeding has been identified.

A new platelet-activating factor antagonist (CV-6209) in preservation of heart and lung for transplantation.

The objective of this experimental protocol was to evaluate the protective effect of a new, potent platelet-activating factor (PAF) antagonist CV-6209 and the use of this compound in combination with allopurinol on ischemia-reperfusion injury in a swine model of heart-lung transplantation. Forty-two swine were divided into three groups, with seven donors and seven recipients in each. In group A, the PAF antagonist CV-6209 was administered in a single dosage of 1 mg/kg by slow intravenous injection at 1 hour before crossclamping of the aorta in both donors and recipients. In group B the combination of allopurinol and the PAF antagonist CV-6209 was used. Allopurinol was administered as a pretreatment regime of 50 mg/kg/day for 3 days prior to ischemia. The PAF antagonist dosage and regime of administration were the same as in group A, and both donors and recipients were pretreated with this combination. Group C was the control in which heart-lung transplantations were performed without interventional therapies. Based on the comparison of pre- and post-transplantation assessments of cardiac and pulmonary functional integrity within groups, and post-transplantation among groups, animals in groups A and B were significantly (P < 0.05) better protected from ischemia-reperfusion injury than animals in group C. The difference between groups A and B, however, was insignificant at all times. Morphological findings are in agreement with measures of physiological variation among experimental groups. It is suggested that the new PAF antagonist CV-6209 is effective in the prevention of heart and lung ischemia-reperfusion injury with and without allopurinol pretreatment.

Medium aperture meso-caval shunts reliably prevent recurrent variceal hemorrhages.

BACKGROUND: Objectives of partial medium aperture mesocaval shunts (MCS) include reduction of portal hypertension to prevent recurrent variceal hemorrhage, preservation of portal flow through liver while maintaining an intact porta hepatis to facilitate a future liver transplant (OLTx). PATIENTS AND METHODS: Fifteen patients were retrospectively analyzed to review the indications for the procedure, its short- and long-term complications as well as patency and functional status of the shunt. They were followed for a period of 21 months. RESULTS: The perioperative and long-term mortality rate was 0%. Rebleeding rate perioperatively and in follow-up was 0%. Early shunt nonfunction was 13% and post-shunt encephalopathy (PSE) was 20%. The encephalopathy was grade I to II and controlled medically. Abdominal ultrasound and Doppler confirmed 13 patent shunts (2 patients did not agree to ultrasound) with preserved hepatopetal flow in 10. CONCLUSIONS: Medium aperture MCS utilizing ringed polytetrafluoroethylene (PTFE) grafts safely and reliably prevent recurrent variceal hemorrhage. Encephalopathy is infrequent and mild. This technique preserves the portal venous anatomy making a future OLTx technically easier.

Additive effect of allopurinol and deferoxamine in the prevention of spinal cord injury caused by aortic crossclamping.

Fourteen domestic swine were divided into two groups. Group A (n = 7) was the control group, in which no pharmacologic intervention was applied. In group B (n = 7), the ischemic-reperfused spinal cord was treated with the combination of allopurinol (50 mg/kg/day for 3 days before the day of operation) and deferoxamine (Desferal, 50 mg/kg administered intravenously over 3 to 4 hours). The administration of deferoxamine was completed 1 hour before crossclamping. The crossclamp was placed on the descending aorta just distal to the left subclavian artery for 30 minutes. Proximal hypertension was controlled with sodium nitroprusside and volume depletion. Methods of assessment included an evaluation of the neurologic status of the animals by quantitative Tarlov criteria, blood flow by radiolabeled microspheres, and histologic examination of the spinal cord. All animals in the control group, group A, were completely paraplegic with 0% recovery by Tarlov criteria at 24 hours after the removal of the crossclamp. In contrast, all animals in group B, in which the combination of allopurinol and deferoxamine was used, completely recovered (100% recovery by Tarlov criteria), and at 24 hours after the ischemic episode they were able to walk with no difficulty and had intact sensation. Functional parameters of these animals fully correlated with the morphologic findings. Widespread acute neuronal injury and vacuolation of neuropil were observed in the control group of animals. In contrast, animals in group B showed much less pronounced morphologic changes after the same period of ischemia. In summary, the combined use of these agents significantly (p < 0.001) reduced the incidence of paraplegia induced by aortic crossclamping with 82% additivity.

Correlation of red cell antioxidant status and heart-lung function in swine pretreated with allopurinol (a model of heart-lung transplantation).

Although the protection against myocardial ischemia-reperfusion injury by allopurinol has previously been attributed to inhibition of xanthine oxidase, the demonstration of protective effects in species devoid of detectable myocardial xanthine oxidase activity argues against this hypothesis. In the present study, the effects of allopurinol pretreatment in a model of heart-lung transplantation were examined in swine, a species devoid of myocardial xanthine oxidase activity. Twenty-eight experiments were performed utilizing the heart-lung transplantation model--seven controls (14 animals, 7 donors and 7 recipients) with no preoperative pharmacological intervention, and twenty-one in the experimental group (42 animals, 21 donors and 21 recipients) with donor and recipient pretreated with allopurinol 50 mg/kg/day for 3 days. The effect of allopurinol was determined on day 2 blood samples assessing red cell antioxidant status by measurement of malondialdehyde (MDA) formation in response to in vitro peroxidative challenge. The experimental group was divided into subgroups--namely, nonresponders (8 pairs of animals) and responders (13 pairs of animals) based on the range (mean +/- 2 SD) of erythrocyte MDA levels in the control group. Heart-lung transplantation was performed in the three groups (control [7], nonresponders [8], and responders [13]) on day 3 following the final dose of allopurinol administration in the experimental group. Based on postsurgical assessments of cardiac and pulmonary function integrity, animals showing the greatest red cell antioxidant response following allopurinol treatment showed significantly better recovery compared with the control group. In contrast, animals that did not respond to allopurinol pretreatment showed results similar to those of the control (i.e., untreated) group. Furthermore, red cell MDA levels in all the allopurinol-treated animals were found to correlate positively (P < 0.001) with the extent of myocardial and lung dysfunction, as indicated by cardiac index and lung water measurements, respectively. The present study suggests that allopurinol protection against ischemia-reperfusion injury may involve generalized alterations in tissue antioxidant status, and that the measurement of erythrocyte susceptibility to oxidative challenge could provide a useful approach to optimizing the effectiveness of therapeutic interventions undertaken prior to surgery in order to minimize the risk of damage resulting from postischemic tissue reperfusion.

Comparison of new iron chelating agents in the prevention of ischemia/reperfusion injury: a swine model of heart-lung transplantation.

The preservation of the heart and lung for transplantation remains a major concern in extended ischemic intervals. This experimental endeavor evaluates and compares the efficacy of iron chelating agents such as high molecular weight deferoxamine and 21-aminosteroid (U74006F) in a swine model of heart-lung transplantation. Heat-lung blocks were exposed to 4 h and 45 min of ischemia and 2 h of reperfusion. Animals were divided into three groups. Group A was a control without pharmacological intervention. In groups B and C, 21-aminosteroid (U74006F), 10 mg/kg, and high molecular weight deferoxamine, 50 mg/kg, were used, respectively. The results of functional parameters (cardiac index, stroke index, lung water, PO2, PCO2, alveolar-arterial gradient, and alveolar-arterial ratio) demonstrated superior heart and lung function for group C, where high molecular weight deferoxamine was used. Alterations of heart and lung function were significantly more (p less than .001) for control animals and for group B where U74006F was used. This study suggests that formation of hydroxyl radicals was affected by chelation of iron with high molecular weight deferoxamine, which reflects better heart and lung function and consequently less damage to this group of animals. The compound 21-aminosteroid U74006F failed to protect the heart and lung from ischemic-reperfusion injury in this model of heart-lung transplantation.

Effects of platelet-activating factor antagonist CV-3988 in preservation of heart and lung for transplantation.

The preservation of heart and lung for transplantation remains a major concern in extended ischemic intervals. This experiment evaluated the effect of high molecular weight deferoxamine and a platelet-activating factor antagonist (CV-3988) in ischemic reperfused tissue. Heart-lung transplantation was performed in a swine model after 4 hours 45 minutes of ischemia. Animals were divided into three groups. Group A was a control without pharmacological intervention. In group B, high molecular weight deferoxamine, 50 mg/kg, was used, and in group C, platelet-activating factor antagonist CV-3988, 10 mg/kg, was used. The results of functional variables (cardiac index, stroke index, lung water, oxygen and carbon dioxide tensions, alveolar-arterial gradient, and alveolar-arterial ratio) demonstrated superior heart and lung function for groups B and C compared with the control group. These alterations of heart and lung function were significantly less (p less than 0.001) in group C, in which the platelet-activating factor antagonist (CV-3988) was used. The study revealed that formation of hydroxyl radicals and platelet-activating factor play an important role in the pathogenesis of ischemia reperfusion injury. Prevention of hydroxyl radical formation with high molecular weight deferoxamine and inactivation of platelet-activating factor with CV-3988 reduce the ischemia-reperfusion injury significantly.