In partial liver transplant, a reduction in the intrahepatic vascular bed produces a rise in the portal vein flow and the portal venous pressure gradient, leading to endothelial and, thereby, hepatocellular injury and death in a process known as “small-for-size” (SFS) syndrome.
To demonstrate that a calibrated portocaval shunt prevents superfluous inflow in a porcine model of SFS transplant.
Donor pigs (15–20 kg) underwent 70% hepatectomy. In 2 groups, a 6 mm (S6) (n = 6) or 12 mm (S12) (n = 6) Gore-Tex shunt was placed between the portal vein and infrahepatic inferior vena cava. In a third group, no portocaval shunt was placed (SFS) (n = 17). Grafts were stored for 5 hours at 4°C and then transplanted into recipients (30–35 kg).
Five-day survival was 29% in SFS, 100% in S6, and 0 in S12. Postreperfusion portal vein flow was 4-, 2-, and 1-times flow at baseline in SFS, S6, and S12, respectively. With respect to portal venous pressure gradient, both the 6- and 12-mm shunts effectively decompressed the portal bed. Aspartate aminotransferase and bilirubin rose and the Quick prothrombin time fell in all animals after reperfusion but improved significantly by day 5 in S6. Serum levels of endothelin-1 remained elevated in SFS and S12 but returned to baseline by 12 hours in S6: 2.76 (2.05–4.08) and 2.04 (1.97–2.12) versus 0.43 (0.26–0.50) pg/mL, respectively (P < 0.05 for both comparisons).
A calibrated portocaval shunt that maintains portal vein flow about twice its baseline value produces a favorable outcome after SFS liver transplantation, avoiding endothelial injury due to portal hyperperfusion or to hypoperfusion because of excess shunting.
In “small-for-size” (SFS) liver transplant, portal vein flow increases approximately four-fold over baseline and causes significant stress in the hepatic sinusoid. In this porcine model of SFS liver transplant, a calibrated portocaval shunt was created to prevent the deleterious consequences of this portal hyperperfusion. Shunts that maintained PVF around twice baseline protected the sinusoidal endothelium and resulted in 100% survival at five days.
*Departments of Surgery
‡Liver Unit, Institut de Malaties Digestives, Hospital Clínic, CIBERehd, IDIBAPS, University of Barcelona, Barcelona, Spain.
Reprints: Constantino Fondevila, MD, PhD, Liver Transplant Unit, Department of Surgery, Hospital Clínic, University of Barcelona, C/Villarroel 170, 08036 Barcelona, Spain. E-mail: email@example.com.
Supported by an F.I.S. Grant 04/1238 from the Instituto de Salud Carlos III, Spain; a University Researcher Grant from W. L. Gore & Associates, Inc., Flagstaff, AZ; and a grant from Nycomed, Linz, Austria. A. J. H. was supported by grants from the Fundación BBVA and the Vanderbilt Medical School Medical Scholars Program. CIBERehd is funded by the Instituto de Salud Carlos III, Spain.
Current address of AJH: Department of Surgery, Barnes-Jewish Hospital, Washington University in St. Louis, St. Louis, MO 63110.