Hepatic ischemic preconditioning increases portal vein flow in experimental liver ischemia reperfusion injury

BACKGROUND: Ischemic preconditioning(IPC) has been shown to decrease liver injury and to increase hepatic microvascular perfusion after liver ischemia reperfusion. This study aimed to evaluate the effects of IPC on hemodynamics of the portal venous system. METHODS: Thirty-two rats were randomized into two groups: IPC group and control group. The rats of the IPC group underwent IPC by 10 minutes of liver ischemia followed by 10 minutes of reperfusion before liver ischemia, and the rats of the control group were subjected to 60 minutes of partial liver ischemia. Non-ischemic lobes were resected immediately after reperfusion. The animals were studied at 4 hours and 12 hours after reperfusion. Mean arterial pressure, heart rate, portal vein flow and pressure were analyzed. Blood was collected for the determination of the levels of aspartate aminotransferase, alanine aminotransferase, calcium, lactate, pH, bicarbonate, and base excess. RESULTS: IPC increased the mean portal vein flow at 4 hours and 12 hours after reperfusion. IPC recovered 78% of the meanportal vein flow at 12 hours after reperfusion. IPC decreased the levels of aspartate aminotransferase, alanine aminotransferase and lactate, and increased the levels of ionized calcium, bicarbonate and base excess at 12 hours after reperfusion. CONCLUSIONS: This study demonstrated that IPC increases portal vein flow and enhances hepatoprotective effects in liver ischemia reperfusion. The better recovery of portal vein flow after IPC may be correlated with the lower levels of transaminases and with the better metabolic profile.

Pentoxifylline enhances the protective effects of hypertonic saline solution on liver ischemia reperfusion injury through inhibition of oxidative stress

BACKGROUND：Liver ischemia reperfusion（IR）injury triggers a systemic inflammatory response and is the main cause of organ dysfunction and adverse postoperative outcomes after liver surgery.Pentoxifylline（PTX）and hypertonic saline solution（HTS）have been identified to have beneficial effects against IR injury.This study aimed to investigate if the addition of PTX to HTS is superior to HTS alone for the prevention of liver IR injury.METHODS： Male Wistar rats were allocated into three groups. Control rats underwent 60 minutes of partial liver ischemia, HTS rats were treated with 0.4 mL/kg of intravenous 7.5% NaCl 15 minutes before reperfusion, and HPTX group were treated with 7.5% NaC1 plus 25 mg/kg of PTX 15 minutes before reperfusion. Samples were collected after reperfusion for determination of ALT, AST, TNF-α, IL-6, IL-10, mitochondrial respiration, lipid peroxidation, pulmonary permeability and myeloperoxidase. RESULTS： HPTX significantly decreased TNF-α 30 minutes after reperfusion. HPTX and HTS significantly decreased ALT,AST, IL-6, mitochondrial dysfunction and pulmonary myelo- peroxidase 4 hours after reperfusion. Compared with HTS only, HPTX significantly decreased hepatic oxidative stress 4 hours after reperfusion and pulmonary permeability 4 and 12 hours after reperfusion. CONCLUSION： This study showed that PTX added the beneficial effects of HTS on liver IR injury through decreases of hepatic oxidative stress and pulmonary permeability.

Successful liver allograft inflow reconstruction with the right gastroepiploic vein

Portal vein thrombosis is a common complica- tion in cirrhotic patients. When portal vein thrombectomy is not a suitable option, a large collateral vessel can be used for allograft venous inflow reconstruction. We describe an unusu- al case of successful portal revascularization using the right gastroepiploic vein. The patient underwent a cadaveric or- thotropic liver transplantation with end-to-end anastomosis of the portal vein to the right gastroepiploic vein. Six months after liver transplantation the patient is well with good liver function. The use of the right gastroepiploic vein for allograft venous reconstruction is feasible and safe, with a great advan- tage of avoiding the need of venous jump graft.

Does bilioenteric anastomosis impair results of liver resection in primary intrahepatic lithiasis?

AIM:To evaluate the long-term results of liver resection for the treatment of primary intrahepatic lithiasis.Prognostic factors,especially the impact of bilioenteric anastomosis on recurrence of symptoms were assessed.METHODS:Forty one patients with intrahepatic stones and parenchyma fibrosis/atrophy and/or biliary stenosis were submitted to liver resection.Resection was associated with a Roux-en-Y hepaticojejunostomy in all patients with bilateral stones and in those with unilateral disease and dilation of the extrahepatic biliary duct(>2 cm).Late results and risk factors for recurrence of symptoms or stones were evaluated.RESULTS:There was no operative mortality.After a mean follow-up of 50.3 mo,good late results were observed in 82.9% of patients;all patients submitted to liver resection alone and 58.8% of those submitted to liver resection and hepaticojejunostomy were free of symptoms(P=0.0006).Patients with unilateral and bilateral disease showed good late results in 94.1% and 28.6%,respectively(P<0.001).CONCLUSION:Recurrence of symptoms in patients with hepaticojejunostomy showed that this may not be the ideal solution.Further studies are needed to establish the best treatment for patients with bilateral stones or unilateral disease and a dilated extrahepatic duct.