Partial portal vein arterialization in acute liver failure

A modified kidney-sparing portal vein arterialization model of heterotopic auxiliary liver transplantation increases liver IL-6, TNF-α, and HGF levels and enhances liver regeneration: an animal model

BACKGROUND AND AIM

The success of partial donor liver transplantation is affected by the implantation site of the donor liver and the vascular reconstruction approach. We investigated the effects of different donor liver implantation sites and vascular reconstruction approaches on liver regeneration using a rat kidney-sparing heterotopic auxiliary liver transplantation model, with portal vein arterialization (PVA).

METHODS

Sixty male Sprague-Dawley rats underwent end-to-end anastomosis of the donor liver portal vein and the right renal artery stent (control group), or end-to-side anastomosis of the donor liver portal vein and the left common iliac artery (experimental group).

RESULTS

The experimental group had significantly lower plasma levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, and cholinesterase than the control group (all, P < 0.05). The levels of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and hepatocyte growth factor (HGF) in the liver were significantly higher in the experimental group than that in the control group (all, P < 0.05). Hematoxylin and eosin (HE) staining of the liver tissue specimens indicated that the experimental group had greater hepatocyte regeneration compared to the control group.

CONCLUSIONS

The modified kidney-sparing PVA model of heterotopic auxiliary liver transplantation is more conducive to liver regeneration with quicker return of liver function.

Portal vein arterialization as a salvage procedure in hepatopancreatobiliary surgery: a systematic review

Background

Portal vein arterialization (PVA) is a possible option when hepatic artery reconstruction is impossible during liver resection. The aim of this study was to review the literature on the clinical application of PVA in hepatopancreatobiliary (HPB) surgery.

Methods

We performed a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We systematically searched the PubMed, Embase and Web of Science databases until December 2019. Experimental (animal) studies, review articles and letters were excluded.

Results

Twenty studies involving 57 patients were included. Cholangiocarcinoma was the most common indication for surgery (40 patients [74%]). An end-to-side anastomosis between a celiac trunk branch and the portal vein was the main PVA technique (35 patients [59%]). Portal hypertension was the most common long-term complication (12 patients [21%] after a mean of 4.1 mo). The median follow-up period was 12 (range 1–87) months. The 1-, 3- and 5-year survival rates were 64%, 27% and 20%, respectively.

Conclusion

Portal vein arterialization can be considered as a rescue option to improve the outcome in patients with acute liver de-arterialization when arterial reconstruction is not possible. To prevent portal hypertension and liver injuries due to thrombosis or overarterialization, vessel calibre adjustment and timely closure of the anastomosis should be considered. Further prospective experimental and clinical studies are needed to investigate the potential of this procedure in patients whose liver is suddenly de-arterialized during HPB procedures.

Partial Portal Vein Arterialization to Treat Toxic Acute Liver Failure in Elderly Rats

INTRODUCTION

Toxic acute liver failure can be fatal even after liver transplantation. Since there are data only in young rats, the aim of our study was to verify the effectiveness of the increase of oxygen to the liver by partial portal vein arterialization (PPVA) in elderly rats with acute liver failure induced by carbon tetrachloride (CCl₄) intoxication.

METHODS

Twenty elderly (30 months) Sprague-Dawley rats underwent a CCl₄ intoxication (5 mL/kg). Animals were divided after 24 hours (n = 10 per group) to either undergo PPVA (G1, treated group) or be untreated (G2, control group). PPVA consisted of a shunt between the left renal artery and splenic vein after nephrectomy and spelnectomy. The G2 group animals underwent nephrectomy and splenectomy only. The 10-day survival was evaluated. Before euthanasia, blood samples from the portal vein were detected for blood gas analysis. Liver injury was evaluated by the serum alanine aminotransferase (ALT) and prothrombin time levels. Histology was done to evaluate the liver necrosis. Hepatocyte regeneration was assessed by the mitotic index at immunohistochemistry.

RESULTS

The PPVA has resulted in a significant increase in the oxygen partial pressure and saturation in portal blood. A survival improvement at 10 days was registered in the PPVA-treated rats (90% vs 30%; P = .0065). After 24 hours from intoxication, ALT was high in both groups. A rapid decrease of ALT was observed in G1 as compared to G2. At the same time, livers showed a severe centrolobular necrosis. In the suviving G2 rats, a moderate necrosis was present, while only a mild necrosis was observed in the G1 rats. An higher mitotic index was detected in rats treated with PPVA.

CONCLUSIONS

In our experimental study, the presence of oxygenated blood in the portal venous system following the PPVA procedure had positive effects on liver regeneration and rats' survival. The PPVA treatment had beneficial effects in elderly rats.

Partial Portal Vein Arterialization Attenuates Acute Bile Duct Injury Induced by Hepatic Dearterialization in a Rat Model

Hepatic infarcts or abscesses occur after hepatic artery interruption. We explored the mechanisms of hepatic deprivation-induced acute liver injury and determine whether partial portal vein arterialization attenuated this injury in rats. Male Sprague-Dawley rats underwent either complete hepatic arterial deprivation or partial portal vein arterialization, or both. Hepatic ischemia was evaluated using biochemical analysis, light microscopy, and transmission electron microscopy. Hepatic ATP levels, the expression of hypoxia- and inflammation-associated genes and proteins, and the expression of bile transporter genes were assessed. Complete dearterialization of the liver induced acute liver injury, as evidenced by the histological changes, significantly increased serum biochemical markers, decreased ATP content, increased expression of hypoxia- and inflammation-associated genes and proteins, and decreased expression of bile transporter genes. These detrimental changes were extenuated but not fully reversed by partial portal vein arterialization, which also attenuated ductular reaction and fibrosis in completely dearterialized rat livers. Collectively, complete hepatic deprivation causes severe liver injury, including bile infarcts and biloma formation. Partial portal vein arterialization seems to protect against acute ischemia-hypoxia-induced liver injury.

Portal blood arterialization with an extracorporeal device to treat toxic acute hepatic failure in a swine model

PURPOSE

This study aimed to determine whether a controlled portal blood arterialization by a liver extracorporeal device (L.E.O2 NARDO) is effective in treating acute hepatic failure (AHF) induced through CCl4 administration in a swine model.

METHODS

20 swine with AHF induced by intraperitoneal injection of carbon tetrachloride (CCl4) in oil solution, were randomly divided into two groups: animals receiving L.E.O2 NARDO treatment 48 h after the intoxication (study group); animals sham operated 48 h after the intoxication (control group). Blood was withdrawn from the iliac artery and reversed in the portal venous system by an interposed extracorporeal device. Each treatment lasted 6 h. The survival was assessed at 5 days after L.E.O2 NARDO treatment or sham operation. In both groups blood samples were collected for biochemical analysis at different time points and liver biopsies were collected 48 h after intoxication and at sacrifice.

RESULTS

We observed decreased transaminases levels and a more rapid INR recovery in the study group, as compared to the control group. Eight animals of the study group vs. two animals of the control group survived at five days after surgery with a statistically significant difference (p<0.05). Liver biopsies performed at sacrifice showed a reduction of the damaged hepatic areas in the study group as compared to the control group.

CONCLUSIONS

Arterial blood supply in the portal system through the L.E.O2 NARDO device is easily applicable, efficacious, and safe in a swine model of AHF induced by CCl4 intoxication.