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We evaluated the effects of alpha-tocopherol (vitamin E) on the products of lipid peroxidation and serum creatinine levels in a rat model of renal ischemia-reperfusion. The animals were submitted to sham operation or renal ischemia-reperfusion, and they were pretreated with alpha-tocopherol or the vehicle saline. In four groups, we analyzed the lipid peroxidation products by measuring malondialdehyde and chemiluminescence levels. In the other three groups, we studied the serum creatinine levels after the procedures. In our study, the pretreatment with alpha-tocopherol reduced significantly the lipid peroxidation of renal cells and renal dysfunction induced by renal ischemia-reperfusion in rats.

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Caroli's disease, characterized by segmental or diffuse dilation of the intrahepatic biliary ducts, is a rare disease which is difficult to treat. The course of the disorder is characterized by recurrent episodes of cholangitis and hospital stays, with a consequent loss of quality-of-life and productive capacity, often ending in death due to uncontrolled infection. Endoscopic drainage of the bile duct, percutaneously or surgically, is palliative, and presents bad results in the follow-up of these patients. Orthotopic liver transplantation appears to be an effective curative option for the treatment of patients with Caroli's disease associated to complications. The authors present the course of two cases of this disease, associated with congenital fibrosis of the liver worsened by repeated episodes of cholangitis, submitted to orthotopic liver transplantation.

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The purpose of the present study is to compare postoperative analgesia offered by the simple instillation of local anesthetic on the surgical wound, its infiltration with the same local anesthetic, and the use of an intravenous opioid. Sixty patients were divided into the three analgesia groups to be studied: instillation of local anesthetic (Group I), injection of local anesthetic (Group II), and intravenous opioid (Group III). The pain was quantified using the visual analogue scale. It was observed that there was better analgesia in Groups I and II during the first 6 hours postoperatively as compared with Group III (P < 0.0001). At the end of the 12 hours the three modes of analgesia proved comparable. However, after 24 hours there was better analgesic development in Group I, whereas Group II had greater postoperative morbidity. We conclude that the instillation of local anesthesia provides analgesia during the immediate postoperative period comparable to local infiltration using the same anesthetic. Both regional analgesia methods are more effective analgesics during the first 6 hours than are intravenous opioids. Furthermore the simple instillation of local anesthetic allows better analgesic evolution of the surgical wound after the first 24 hours considering the lower rate of resulting complications.

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OBJECTIVE: To study the role of the L-arginine/nitric oxide (NO) pathway during renal ischaemia-reperfusion in rats. DESIGN: Randomised experimental study. SETTING: Teaching hospital, Brazil. ANIMALS: 97 male Wistar rats randomly assigned to 4 groups for the assessment of renal dysfunction and to 6 groups for the assessment of the oxidative stress induced on renal cell membranes by ischaemia-reperfusion. INTERVENTIONS: The animals underwent sham-operation or renal ischaemia-reperfusion (n = 9 each) with or without pretreatment with L-arginine (a NO donor) or L-NAME (N(omega)-nitro-L-arginine methyl ester--an inhibitor of NO production) (n = 10 each). MAIN OUTCOME MEASURES: Serum creatinine concentrations and oxidative stress by chemiluminescence initiated by the tert-butyl hydroperoxide technique. RESULTS: Renal ischaemia-reperfusion significantly worsened renal dysfunction and increased oxidative stress in the ischaemia-reperfusion group after 24 and 96 hours of reperfusion compared with the control group (p < 0.05). Pretreatment with L-NAME slightly but not significantly increased serum creatinine concentrations after 24 and 96 hours of reperfusion together with activity of reactive oxygen species during renal ischaemia-reperfusion. L-arginine also significantly protected renal function and reduced the increment in the amount of chemiluminescence induced by giving L-NAME during 24 and 96 hours of reperfusion (p < 0.05). CONCLUSION: The L-arginine/NO pathway seems to have a slightly protective effect on the kidney after renal ischaemia-reperfusion injury in rats. These results need to be confirmed by studies in human beings.

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BACKGROUND/AIMS: Some studies have shown that postischemic hepatic dysfunction is mainly due to oxygen free radicals that are generated by xanthine oxidase. The present study was undertaken to determine the effect of allopurinol, an inhibitor of xanthine oxidase, on oxidative stress, liver injury and histologic alterations induced by hepatic ischemia-reperfusion in rats. METHODS: One hundred and sixty Wistar rats were used and divided into three groups. Group 1: sham operation; group 2: 50 min of ischemia followed by 1 h of reperfusion, and group 3: pretreatment with allopurinol and 50 min of ischemia followed by 1 h of reperfusion. The effect of allopurinol was evaluated by plasma levels of alanine aminotransferase and aspartate aminotransferase, histopathologic studies, and lipid peroxidation measured by the thiobarbituric acid reactive substances method and chemiluminescence initiated by tert-butyl hydroperoxide technique. RESULTS: Ischemia followed by reperfusion promoted an increase in lipid peroxidation of the hepatic cells when compared to the sham-operated group (p<0.05). This increase was attenuated in the group treated with allopurinol (p< 0.05). Allopurinol also showed a protective effect on hepatocellular necrosis (p<0.05), and the plasma levels of liver enzymes returned earlier to the normal range in rats pretreated with allopurinol in comparison to those that did not receive the drug (p<0.05). CONCLUSIONS: Allopurinol exerted a protective effect on hepatic ischemia and reperfusion in rats. The administration of this drug prior to liver operations should be considered to be submitted to trials in humans.

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The present study was undertaken to determine the effect of ischemia and reperfusion on oxidative stress in hepatic cirrhosis induced by carbon tetrachloride (CCl4) in rats by the evaluation of lipid peroxidation products (LPO). Cirrhosis of the liver was induced by CCl4 administration. This drug was dissolved in mineral oil and the control group received only mineral oil intraperitoneally. Forty-five minutes of ischemia followed by one hour of reperfusion were performed. LPO products were evaluated by the thiobarbituric acid reactive substances method (TBARS) and chemiluminescence initiated by tert-butyl hydroperoxide technique (CL). The liver was submitted to histologic evaluation to check whether cirrhosis was present. The results demonstrated that ischemia-reperfusion caused an increase of LPO products in cirrhotic rats when compared to the control group (p < 0.05). Hepatic cirrhosis was present in all animals treated with CCl4 and no significant histologic alterations were observed in the control group. According to this study, we can conclude that the effect of ischemia and reperfusion in a rat model of hepatic cirrhosis caused a significant increase of the hepatic-levels of LPO products when compared to the noncirrhotic livers.

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BACKGROUND/AIMS: Palliative treatment of advanced esophageal carcinoma by esophageal tunnelization with a prosthesis allows immediate relief of dysphagia. However, the procedure is subject to a high rate of morbidity, including gastroesophageal reflux (GER) present in all patients with a prosthesis positioned through the gastroesophageal junction, resulting in complications (pyrosis, aspiration pneumonias, sleep disorders) and reduced quality of life in these patients who already have a lower rate of survival. In an attempt to reduce GER and its complications, the authors created a surgical prosthesis coupled to an anti-reflux valve system, comparing it to the use of an esophageal prosthesis without an anti-reflux valve mechanism. METHODOLOGY: Twenty-two patients were allocated to 2 tunnelization groups: esophageal prosthesis without an anti-reflux valve mechanism (group 1) and surgical prosthesis coupled to an anti-reflux valve system (group 2). The GER was quantified measuring esophageal-gastric pH, and using fluoroscopy, contrast radiographs and esophageal emptying scintigraphy. Initially, the pH of secretions in S1 (esophagus) and S2 (stomach) was determined using reagent strips after aspirating their contents with different syringes. First with the patient seated at rest in bed, later performing a Valsalva maneuver, deep breathing and forced coughing. The same procedure was performed with the patient in left lateral decubitus, right lateral decubitus, and dorsal decubitus with the head of the bed lowered to 20 degrees. After finishing these maneuvers, 15 ml of 1 molar acetic acid were infused through the catheter positioned in the antrum, and, after 5 min, S1 and S2 material sampling was repeated in the same positions as mentioned above. RESULTS: The pH values between the various positions and maneuvers performed in each group separately were not significantly different, but, if we compare the 2 groups, and the secretions obtained in S1 and S2, there was a significant difference in pH measures in all positions. In the patients in group 1, S1 presented a mean pH ranging from 2.87-3.62 in the initial measures, and between 2.17 and 3.5 after the infusion of 15 ml of 1 molar acetic acid. On the other hand, in group 2, the mean pH of S1 remained between 6.34 and 8.32 in the initial measures and between 4.99 and 7.33 in the presence of acid infusion. At the level of S2, the pH remained unchanged between 2 and 2.7, in both groups. CONCLUSIONS: The authors conclude that the association of an esophageal prosthesis with a valve system significantly reduces GER, as compared with its use alone. Furthermore, it allows marked reduction of the symptoms and resulting complications, and does not interfere clinically with esophageal emptying. It thus significantly improves the quality of life of these patients.

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BACKGROUND/AIMS: Whether the frequency of anastomotic leak after pancreaticoduodenectomy for benign diseases is greater than for malignant conditions and whether fistula development is associated with surgical mortality remains controversial. The purpose of this study is to compare the incidence of anastomotic leak in patients operated on for chronic pancreatitis and periampullary tumors. METHODOLOGY: The authors retrospectively reviewed the charts of 67 patients (46 males, 21 females, mean age 47 years) submitted to pancreaticoduodenectomy for chronic pancreatitis and periampullary tumors between 1990 and 1996. RESULTS: In 44 patients with periampullary cancers, pancreatic fistula developed in 13 (29%) cases, and in 6 (26%) of the 23 patients with chronic pancreatitis (p>0.05). Of the 19 patients who developed this complication, 5 (26.3%) died, and in the remaining 48 cases, there was only one (2.1%) death (p<0.05). CONCLUSION: The frequency of pancreatic fistula after pancreaticoduodenectomy in patients with periampullary tumors and chronic pancreatitis is not different, but the presence of a fistula is strongly involved in postoperative mortality.

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This study reports our experience with 31 patients who underwent biliary reconstructions due to iatrogenic lesions of the main biliary tract. The technique of Hepp and Couinaud, associated with the use of transhepatic Silastic tubes, was utilized in 90% of the patients, and the mucosal graft was employed in only three patients. The recommended time for keeping the transhepatic tube in place was 6 months. In order to prevent subphrenic fluid collection between the tube exit orifice in the hepatic parenchyma and the abdominal wall, the tubes were protected with a Penrose drain over the course of their use. This tactic appeared effective. The immediate postoperative mortality was 9%, and the long-term results, with a mean follow-up period of 44 months, were considered good in 92% of the patients who survived surgery.

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