Effect of Elevated Intra-Abdominal Pressure on Portal Vein and Superior Mesenteric Artery Blood Flow in a Rat (original) (raw)
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Portal venous pressure in biliary atresia
Journal of Pediatric Surgery, 2012
Biliary atresia (BA) is characterized by a variable degree of fibrosis within the liver, causing portal hypertension sometimes evident at the time of presentation. Aim: The aims of this study are to measure portal venous pressure (PVP) at time of Kasai portoenterostomy (KP) and to investigate the value of surrogate indices. Methods: At the time of KP and before any liver manipulation, an attempt was made to recanalize the umbilical vein, allowing a catheter to be sited. Preoperative noninvasive variables included maximum splenic diameter (on ultrasound); platelet count, aspartate aminotransferase, and bilirubin; and the aspartate aminotransferase/platelet index ratio (APRi). Clearance of jaundice was defined as achieving a bilirubin of less than 20 μmol/L. Data are quoted as median (range). Nonparametric statistical tests were used, and P b .05 was regarded as significant. Results: Portal venous pressure measurements were available in 61 infants, who underwent a KP during the period February 2007 to October 2010. Median age at KP was 52 (19-151) days. Median PVP was 9 (3-26) mm Hg and was significantly lower in those with isolated (n = 47) BA vs cytomegalovirus-associated BA (n = 6) (8 vs 17 mm Hg; P = .
Hepatic Vascular Response to Elevated Intraperitoneal Pressure in the Rat
Journal of Surgical Research, 2002
The rat is increasingly being used to study the physiological response to elevated intra-abdominal pressure (IAP) during laparoscopic surgery. Although decreased portal venous flow associated with the elevated IAP has been reported in large animals, little information is available in rats. Furthermore, the relative blood flow changes in the hepatic artery and portal vein have not been reported. Therefore, this study was performed to elucidate the change in systemic and splanchnic circulation, including hepatic arterial and portal venular flow, during pneumoperitoneum in rats. Sprague-Dawley rats were assigned into either a ventilated or nonventilated group and then subjected to various levels of IAP (0, 5, 10, and 20 mm Hg) using carbon dioxide gas. At each pressure, both cardiac output and splanchnic organ flow were determined using fluorescent microspheres. There was no obvious hemodynamic difference between the ventilated and nonventilated groups. Mean arterial pressure and cardiac index were significantly lower with 20 mm Hg of IAP compared to 0 mm Hg in both groups. Flow to the spleen, stomach, duodenum, total intestine, and portal vein was all decreased by increasing IAP (P < 0.05 at 20 mm Hg compared to 0 mm Hg) and was significantly correlated to the decrease in cardiac index. However, the hepatic arterial flow was relatively preserved throughout all levels of IAP, suggesting activation of the hepatic arterial buffer response. We conclude that the decreased splanchnic flow during pneumoperitoneum largely depends on the decreased cardiac index. Hepatic artery flow, however, is selectively preserved and may provide protec-tion for liver function during sustained elevations in IAP. © 2002 Elsevier Science (USA)
In vivo (Athens, Greece)
While reduction of portal venous (PV) blood flow has been described in animal models of intra-abdominal hypertension, reports on compensatory changes in hepatic arterial (HA) flow, known as the hepatic arterial buffer response are controversial. Pneumoperitoneum with helium was induced in 13 piglets. Hemodynamic measurements and pathological assessment were conducted at baseline and during the three subsequent phases: Phase A: 45 minutes with a stable intra-abdominal pressure of 25 mmHg; phase B: 45 minutes with a stable intra-abdominal pressure of 40 mmHg; and phase C during which the abdomen was re-explored and reperfusion of the liver was allowed to take place. Phase B pressure was significantly greater than phase A pressure in both the PV and the inferior vena cava, demonstrating a positive association between escalating intra-abdominal hypertension and the pressure in these two vessels (all p<0.001). In contrast, HA pressure was comparable between baseline and phase A, while...
Impact of Endoscopic Biliary Drainage on Intrinsic Hepatic Blood Flow in Human
The Medical Journal of Cairo University
Background: Obstructive jaundice affects a significant portion of people with injurious effect on the liver. Aim of Study: The study aimed to study the impact of biliary drainage on hepatic blood follow. Patients and Methods: This was a prospective study, conducted from January 2018 to December 2018. Thirty-six patients with biliary obstruction aged 21-72 years, 26 out of them have calcular obstructive jaundice, and the rest of the patients have malignant biliary obstruction. The majority of cases were non-cirrhotic (32 versus 4). Liver tests; (bilirubin level, alkaline phosphatase, GGT, albumin, INR, ALT and AST), and Kidney function tests (blood urea and serum creatinin) and CBC were done. Plus, other pre-ERCP assessments were done. Abdominal Ultrasonography (US) and Doppler study of portal and hepatic veins and hepatic artery with measurement of Hepatic artery Resistive Index (RI), Portal vein diameter and congestive index were done, CT and MRCP if indicated and ERCP for all patients. Two weeks after ERCP, all included patients underwent repetition of the same laboratory and Doppler US. Results: Significant changes in patients' laboratories and in liver hemodynamics were noticed after biliary drainage. The mean values of hepatic artery RI were significantly higher and mean values of portal vein maximum velocity (V max) were lower in studied patients before and after biliary drainage. Conclusions: Liver hemodynamics measured by Doppler Ultrasound of hepatic artery RI &V. max of portal vein may be a good predictor of liver injury in biliary obstruction.
Arquivos de Gastroenterologia
BACKGROUND: Biliary atresia represents the most common surgically treatable cause of cholestasis in newborns. If not corrected, secondary biliary cirrhosis invariably results. OBJECTIVE: To evaluate, through multivariate analysis, the prognostic factors associated with the presence of biliary flow and survival with the native liver following Kasai portoenterostomy. METHODS: The study analyzed data from 117 biliary atresia patients who underwent portoenterostomy and had suitable histological material for evaluation. A logistic regression model was used to assess the presence of biliary flow. Survival was investigated through Kaplan-Meier curves and Cox-adjusted models. RESULTS: One third of patients achieved biliary flow and the median age at surgery was 81 days. Age at surgery, albumin, postoperative complications, biliary atresia structural malformation (BASM), liver architecture, larger duct diameter at porta hepatis, and cirrhosis (Ishak score) were the initial variables for the ...
Modulation of hepatic perfusion did not improve recovery from hepatic outflow obstruction
BMC Pharmacology and Toxicology
Background: Focal hepatic venous outflow obstruction frequently occurs after extended liver resection and leads to a portal hypertension, arterial hypoperfusion and parenchymal necrosis. In this study, we investigated the pharmacological modulation of liver perfusion and hepatic damage in a surgical model of hepatic outflow obstruction after extended liver resection by administration of 5 different drugs in comparison to an operative intervention, splenectomy. Methods: Male inbred Lewis rats (Lew/Crl) were subjected to right median hepatic vein ligation + 70% partial hepatectomy. Treatment consisted of a splenectomy or the application of saline, carvedilol or isosorbide-5mononitrate (ISMN) (5 mg • kg −1 respectively 7,2 mg • kg −1 per gavage 12 h −1). The splenectomy was performed during operation. The effect of the treatments on hepatic hemodynamics were measured in non-operated animals, immediately after operation (n = 4/group) and 24 h after operation (n = 5/group). Assessment of hepatic damage (liver enzymes, histology) and liver cell proliferation (BrdU-immunohistochemistry) was performed 24 h after operation. Furthermore sildenafil (10 μg • kg −1 i.p. 12h −1), terlipressin (0.05 mg • kg −1 i.v. 12 h −1) and octreotide (10 μg • kg −1 s.c. 12 h −1) were investigated regarding their effect on hepatic hemodynamics and hepatic damage 24 h after operation (n = 4/group). Results: Carvedilol and ISMN significantly decreased the portal pressure in normal non-operated rats from 11,1 ± 1,1 mmHg (normal rats) to 8,4 ± 0,3 mmHg (carvedilol) respectively 7,4 ± 1,8 mmHg (ISMN). ISMN substantially reduced surgery-induced portal hypertension from 15,4 ± 4,4 mmHg to 9,6 ± 2,3 mmHg. Only splenectomy reduced the portal flow immediately after operation by approximately 25%. No treatment had an immediate effect on the hepatic arterial perfusion. In all treatment groups, portal flow increased by approximately 3-fold within 24 h after operation, whereas hepatic arterial flow decreased substantially. Neither treatment reduced hepatic damage as assessed 24 h after operation. The distribution of proliferating cells appeared very similar in all drug treated groups and the splenectomy group. Conclusion: Transient relative reduction of portal pressure did not result in a reduction of hepatic damage. This might be explained by the development of portal hyperperfusion which was accompanied by arterial hypoperfusion.
Journal of Surgical Research, 1978
There is debate about the extent of mixing of hepatic arterial and portal venous blood in the liver parenchyma and also about the precise anatomical site at which this happens [81. Current concepts suggest that the two inflows of blood mix completely either before or in the sinusoids of the liver [ 151, and it is therefore presumed that the hepatic parenchyma has a completely mixed blood flow. This view is supported by investigations using labeled indicators which show that all but a very small fraction of the total hepatic vascular bed is common to both inputs [4, 71.