Hepatic artery ligation in treatment of carcinoid syndrome.
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SUMMARY: In a patient with malignant carcinoid syndrome with metastasis to the liver, cardiac lesions, pulmonary hypertension, pellagra-like skin lesions and depression developed. Her disability progressed despite medical therapy and two courses of chemotherapy. The primary tumour had been resected but the metastatic mass in the liver could not be resected because of its anatomic position. The dramatic improvement after hepatic artery ligation was correlated with urinary 5-hydroxyindole acetic acid excretion. (+info)
Anatomy of the cystic artery arising from the gastroduodenal artery and its choledochal branch--a case report.
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Variations in the branching pattern of the common hepatic artery often occur and may be encountered during cholecystectomy. Variants of the cystic artery, its branches and relations with the biliary structures and blood vessels emphasise the importance of arterial dissection in biliary surgery. In this study, a rare variant of the cystic artery and its choledochal branch is described. The cystic artery arose from the gastroduodenal artery, passed anterior to structures in the free margin of lesser omentum and travelled a long distance before supplying the gall bladder. A long choledochal branch was noted accompanying the common bile duct. Surgical implications of this variation of the cystic and choledochal arteries are discussed. (+info)
Hepatic neovascularization after partial portal vein ligation: novel mechanism of chronic regulation of blood flow.
(51/997)
The present study was undertaken to investigate hepatic microcirculatory response following partial portal vein ligation (PPVL) in rats. Portal pressure was markedly increased 2-6 wk after PPVL, but no significant reduction in sinusoidal perfusion and hepatocellular injury were detected. However, marked neovascularization was observed in PPVL rats using intravital microscopy and scanning electron microscopy (SEM). Extremely high red blood cell velocity (2,000-4,900 microm/s) was seen in these vessels. Injection of fluorescein sodium via the carotid artery revealed that the neovessels originated from the hepatic arterial vasculature. This was further confirmed by clamping the common hepatic artery and phenylephrine injection from the carotid artery. These vessels maintained sufficient flow after massive sinusoidal shutdown elicited by the portal infusion of endothelin receptor B agonist IRL-1620. SEM also showed extensive neovascularization at the hilum. Additionally, clamping the portal vein decreased sinusoidal perfusion only by 9.5% in PPVL, whereas a 71.2% decrease was observed in sham. These results strongly suggest that the liver maintains its microcirculatory flow by vascular remodeling from the hepatic arterial vasculature following PPVL. (+info)
Minimal protection of the liver by ischemic preconditioning in pigs.
(52/997)
Ischemic preconditioning (IP) protects the rat liver. In pigs, in which hepatic tolerance to ischemia is similar to that in humans, information on IP is lacking. Therefore, in enflurane-anesthetized pigs, hepatic vessels were occluded for 120 min (protocol 1) or 200 min (protocol 2) without (control) and with IP (3 times 10 min ischemia-reperfusion each). In protocol 1, cumulative bile flow (CBF) during reperfusion was greater in IP (47.3 +/- 5.2 ml/8 h) than in control (17.1 +/- 7.8 ml/8 h, P < 0.05). ATP content tended to recover toward normal during reperfusion in IP, whereas it remained at ischemic levels in control. Serum enzyme concentrations increased similarly during reperfusion, and <1% hepatocytes were necrotic or stained terminal deosynucleotidyl transferase-mediated dUTP nick-end labeling-positive in control and IP groups. In protocol 2, no differences in CBF, ATP, or serum enzyme concentrations during reperfusion were measured between control and IP groups, except for a somewhat reduced lactate dehydrogenase in IP. The number of necrotic or terminal deosynucleotidyl transferase-mediated dUTP nick-end labeling-positive hepatocytes tended to be greater in the IP than the control group. Thus IP provides some functional protection against reversible ischemia but no protection during prolonged ischemia in pigs. (+info)
Early detection of hepatic artery thrombosis after liver transplantation by Doppler ultrasonography: prognostic implications.
(53/997)
We assessed the usefulness of routine Doppler ultrasonography for early detection of hepatic artery thrombosis after orthotopic liver transplantation and repercussions in patient prognosis. Seventeen confirmed cases of early hepatic artery thrombosis initially diagnosed by Doppler ultrasonography (10 of them before clinical indication) were reviewed. All patients underwent Doppler ultrasonographic studies in the first 3 days after orthotopic liver transplantation. Twelve cases of hepatic artery thrombosis (70.6%) were detected by this early Doppler ultrasonography. All 10 unsuspected cases of hepatic artery thrombosis and 5 of the 7 cases diagnosed after clinical indication were treated by revascularization. Grafts were salvaged in 80% of asymptomatic patients and in 42.8% of symptomatic patients. Furthermore, biliary complications were less serious in the first group. In conclusion, Doppler ultrasonography performed routinely in the first 3 days after orthotopic liver transplantation may permit early detection of hepatic artery thrombosis, even before clinical indications. This allows hepatic artery repermeabilization before liver function damage, improving graft rescue and patient prognosis. (+info)
Safety and risk of using pediatric donor livers in adult liver transplantation.
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Pediatric donor (PD) livers have been allocated to adult transplant recipients in certain situations despite size discrepancies. We compared data on adults (age > or = 19 years) who underwent primary liver transplantation using livers from either PDs (age < 13 years; n = 70) or adult donors (ADs; age > or = 19 years; n = 1,051). We also investigated the risk factors and effect of prolonged cholestasis on survival in the PD group. In an attempt to determine the minimal graft volume requirement, we divided the PD group into 2 subgroups based on the ratio of donor liver weight (DLW) to estimated recipient liver weight (ERLW) at 2 different cutoff values: less than 0.4 (n = 5) versus 0.4 or greater (n = 56) and less than 0.5 (n = 21) versus 0.5 or greater (n = 40). The incidence of hepatic artery thrombosis (HAT) was significantly greater in the PD group (12.9%) compared with the AD group (3.8%; P =.0003). Multivariate analysis showed that preoperative prothrombin time of 16 seconds or greater (relative risk, 3.206; P =.0115) and absence of FK506 use as a primary immunosuppressant (relative risk, 4.477; P =.0078) were independent risk factors affecting 1-year graft survival in the PD group. In the PD group, transplant recipients who developed cholestasis (total bilirubin level > or = 5 mg/dL on postoperative day 7) had longer warm (WITs) and cold ischemic times (CITs). Transplant recipients with a DLW/ERLW less than 0.4 had a trend toward a greater incidence of HAT (40%; P <.06), septicemia (60%), and decreased 1- and 5-year graft survival rates (40% and 20%; P =.08 and.07 v DLW/ERLW of 0.4 or greater, respectively). In conclusion, the use of PD livers for adult recipients was associated with a greater risk for developing HAT. The outcome of small-for-size grafts is more likely to be adversely affected by longer WITs and CITs. The safe limit of graft volume appeared to be a DLW/ERLW of 0. 4 or greater. (+info)
Hepatic artery thrombosis after orthotopic liver transplantation: a review of nonsurgical causes.
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Hepatic artery thrombosis (HAT) is one of the principal causes of morbidity and graft loss following liver transplantation. There are several risk factors for the development of HAT; technical aspects of the arterial anastomosis are important particularly for early thrombosis, but the improvement of surgical technique has lessened this problem. Apart from technical causes, other risk factors include a variety of conditions such as low donor/recipient age ratio, immunologic factors, clotting abnormalities, tobacco use, and infections. In particular, cytomegalovirus (CMV) infection of endothelial cells has been recently suggested as an infective cause of HAT, as it is known to be followed by a rapid procoagulant response. Thus, latent CMV in an allograft may become activated and promote or contribute to vascular thrombosis. This review evaluates these aspects, focusing on data relating CMV infection or viremia to HAT following liver transplantation. (+info)
Hepatic arteriolo-portal venular shunting guarantees maintenance of nutritional microvascular supply in hepatic arterial buffer response of rat livers.
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To elucidate the hepatic microvascular response upon the hepatic arterial buffer response (HABR), we analysed blood flow (ultrasonic flowprobes) of the hepatic artery (HA) and portal vein (PV), microcirculation (intravital microscopy), and tissue oxygenation (polarography) in anaesthetized Sprague-Dawley rats and re-evaluated the role of adenosine in mediating the HABR by using 8-phenyltheophylline as a competitive antagonist. 2. Upon restriction of PV blood flow to 11 +/- 3 % of baseline values, HA blood flow increased by a factor of 1.77 (P < 0.05), thus confirming HABR. Strikingly, red blood cell velocity and volumetric blood flow in terminal hepatic arterioles (THAs) did not increase but were even found to be slightly decreased, by 8 and 13 %, respectively. In contrast, red blood cell velocity and volumetric blood flow in terminal portal venules (TPVs) decreased to only 66 % (P < 0.05), indicating upstream hepatic arteriolo-portal venular shunting. As a consequence, red blood cell velocity and volumetric blood flow in sinusoids were found to be reduced to only 66-68 % compared with baseline (P < 0.05). Diameters of neither of those microvessels changed, thus excluding THA-, TPV-, and sinusoid-associated mechanisms of vasomotor control in HABR. 3. Tissue PO2 and hepatocellular NADH fluorescence remained unchanged, indicating HABR-mediated maintenance of adequate oxygen delivery, despite the marked reduction of total liver blood flow. Further, hepatic arteriolo-portal venular shunting guaranteed homogeneity of nutritive blood flow upon HABR, as given by an unchanged intra-acinar coefficient of variance of sinusoidal perfusion. 4. Pretreatment of animals with the adenosine antagonist 8-phenyltheophylline completely blocked the hepatic arterial buffer response with the consequence of decreased tissue oxygenation and increased heterogeneity of sinusoidal perfusion. 5. In conclusion, hepatic microhaemodynamics, in particular unchanged diameters of THAs, TPVs and sinusoids, during HABR indicate that reduction in resistance to HA flow is located upstream and functions via hepatic arteriolo-portal venular shunts resulting in equal distribution of microvascular blood flow and oxygen delivery under conditions of restricted PV blood supply. (+info)