Left lobe adult-to-adult living donor liver transplantation: Should portal inflow modulation be added?

Recently, the successful application of portal inflow modulation has led to renewed interest in the use of left lobe grafts in adult-to-adult living donor liver transplantation (LDLT). However, data on the hepatic hemodynamics supporting portal inflow modulation are limited, and the optimal portal circulation for a liver graft is still unclear. We analyzed 42 consecutive adult-to-adult left lobe LDLT cases without splenectomy or a portocaval shunt. The mean actual graft volume (GV)/recipient standard liver volume (SLV) ratio was 39.8% ± 5.7% (median = 38.9%, range = 26.1%-54.0%). The actual GV/SLV ratio was less than 40% in 24 of the 42 cases, and the actual graft-to-recipient weight ratio was less than 0.8% in 17 of the 42 recipients. The mean portal vein pressure (PVP) was 23.9 ± 7.6 mm Hg (median = 23.5 mm Hg, range = 9-38 mm Hg) before transplantation and 21.5 ± 3.6 mm Hg (median = 22 mm Hg, range = 14-27 mm Hg) after graft implantation. The mean portal pressure gradient (PVP - central venous pressure) was 14.5 ± 6.8 mm Hg (median = 13.5 mm Hg, range = 3-26 mm Hg) before transplantation and 12.4 ± 4.4 mm Hg (median = 13 mm Hg, range = 1-21 mm Hg) after graft implantation. The mean posttransplant portal vein flow was 301 ± 167 mL/minute/100 g of liver in the 38 recipients for whom it was measured. None of the recipients developed small-for-size syndrome, and all were discharged from the hospital despite portal hyperperfusion. The overall 1-, 3-, and 5-year patient and graft survival rates were 100%, 97%, and 91%, respectively. In conclusion, LDLT with a left liver graft without splenectomy or a portocaval shunt yields good long-term results for adult patients with a minimal donor burden.

Ishizaki Y ，Kawasaki S ，Sugo H ，Yoshimoto J ，Fujiwara N ，Imamura H ... -  《-》

Portal inflow and pressure changes in right liver living donor liver transplantation including the middle hepatic vein.

The middle hepatic vein may be included in right liver living donor liver transplantation (LDLT) to optimize hepatic venous outflow. We studied the graft's ability to relieve portal hypertension and accommodate portal hyperperfusion with portal manometry and ultrasonic flowmetry. Surgical outcomes with respect to portal hemodynamometry were also investigated. The ages of the recipients and donors for 46 consecutive LDLT procedures were 50 (range, 16-66 years) and 31 years (range, 18-54 years), respectively. The graft to standard liver volume ratio was 47.4% (range, 32.4%-69.0%). The hospital mortality rate was 4.4% as 2 recipients died from a subarachnoid hemorrhage and sepsis. The portal pressure dropped by 8 mm Hg (range, -7 to 19 mm Hg) from 23 (range, 8-37 mm Hg) to 14 mm Hg (range, 10-26 mm Hg) after graft implantation. The portal inflow positively correlated with the portal pressure before native liver hepatectomy (R(2) = 0.305, P = 0.001) and not with the graft size. The portal inflow increased from 81 mL/minute/100 g (range, 35-210 mL/minute/100 g) before donor right hepatectomy to 318 mL/minute/100 g (range, 102-754 mL/minute/100 g) after graft implantation. The graft portal inflow had a positive linear correlation with the recipient portal pressure before native liver total hepatectomy (R(2) = 0.261, P = 0.001) but not after graft implantation, and it had a negative correlation with the graft to standard liver volume ratio (R(2) = 0.247, P = 0.001). Only 1 of the graft biopsies showed moderate sinusoidal congestion. Twelve recipients had Clavien grade 2+ complications that were not related to the portal inflow and pressure or graft size. Right liver LDLT including the middle hepatic vein effectively lowered the recipient portal pressure by allowing unimpeded venous outflow.

Chan SC ，Lo CM ，Ng KK ，Ng IO ，Yong BH ，Fan ST ... -  《-》

Left lobe adult-to-adult living donor liver transplantation: small grafts and hemiportocaval shunts in the prevention of small-for-size syndrome.

Adult-to-adult living donor liver transplantation (AA-LDLT) has better outcomes when a graft weight to recipient weight ratio (GW/RW) > 0.8 is selected. A smaller GW/RW may result in small-for-size syndrome (SFSS). Portal inflow modulation seems to effectively prevent SFSS. Donor right hepatectomy is associated with greater morbidity and mortality than left hepatectomy. In an attempt to shift the risk away from the donor, we postulated that left lobe grafts with a GW/RW < 0.8 could be safely used with the construction of a hemiportocaval shunt (HPCS). We combined data from 2 centers and selected suitable left lobe living donor/recipient pairs. Since January 2005, 21 patients underwent AA-LDLT with left lobe grafts. Sixteen patients underwent the creation of an HPCS between the right portal vein and the inferior vena cava. The portocaval gradient (portal pressure - central venous pressure) was measured before the unclamping of the shunt and 10 minutes after unclamping. The median actual graft weight was 413 g (range = 350-670 g), and the median GW/RW was 0.67 (range = 0.5-1.0). The portocaval gradient was reduced from a median of 18 to 5 mmHg. Patient survival and graft survival at 1 year were 87% and 81%, respectively. SFSS developed in 1 patient, who required retransplantation. Two patients died at 3 and 10 months from a bile leak and fungal sepsis, respectively. The median recipient bilirubin level and INR were 1.7 mg/dL and 1.1, respectively, at 4 weeks post-transplant. One donor had a bile leak (cut surface). This is the first US series of small left lobe AA-LDLT demonstrating that the transplantation of small grafts with modulation of the portal inflow by the creation of an HPCS may prevent the development of SFSS while at the same time providing adequate liver volume. As it matures, this technique has the potential for widespread application and could positively effect donor safety, the donor pool, and waiting list times.

Botha JF ，Langnas AN ，Campos BD ，Grant WJ ，Freise CE ，Ascher NL ，Mercer DF ，Roberts JP ... -  《-》

Impact of portal venous hemodynamics on indices of liver function and graft regeneration after right lobe living donor liver transplantation.

The aim of this study was to evaluate the effects of portal hemodynamics on indices of liver function and graft regeneration in patients after adult right lobe living donor liver transplantation (R-LDLT). Sixty-four patients who underwent R-LDLT and had an uneventful postoperative course were enrolled in this study. The contribution of portal flow was greater to the recipient grafts versus the donor livers (90.74% versus 69.12%, P < 0.0001). Portal flow variations decreased significantly during the first 10 days after R-LDLT (P < 0.0001); variations in the hepatic arterial flow were more constant during this period (P = 0.812). The mean portal venous pressure (PVP) before recipient hepatectomy (the initial PVP) was 23.1 ± 4.0 mm Hg; the mean PVP after reperfusion (the final PVP) was 15.0 ± 4.3 mm Hg (P < 0.0001). Furthermore, the mean hepatic portal venous gradient (ie, PVP - central venous pressure) before recipient hepatectomy was 17.1 ± 4.3 mm Hg; it decreased to 10.6 ± 4.5 mm Hg after reperfusion (P < 0.0001). These findings suggest that after graft reperfusion, the vascular resistance of the hepatic parenchyma decreased, and there was an associated mild decrease in the portal hypertension. Multiple regression analysis indicated that PVPs correlated significantly with indices of liver function after living donor liver transplantation (P < 0.05). Patients were separated into 4 groups according to their PVP values: group A (initial PVP ≥ 23 mm Hg, final PVP ≥ 15 mm Hg), group B (initial PVP < 23 mm Hg, final PVP ≥ 15 mm Hg), group C (initial PVP ≥ 23 mm Hg, final PVP < 15 mm Hg), and group D (initial PVP < 23 mm Hg, final PVP < 15 mm Hg). Immediately after R-LDLT, the peak values for aspartate aminotransferase, alanine aminotransferase, the international normalized ratio and the average ascites production varied appreciably in these groups. The regeneration rate of the liver graft 3 months after R-LDLT was significantly greater in group A versus the other groups. In conclusion, PVP is a significant hemodynamic factor that influences the functional status of the liver and graft regeneration after R-LDLT.

Wu TJ ，Dahiya D ，Lee CS ，Lee CF ，Chou HS ，Chan KM ，Lee WC ... -  《-》

Portal pressure <15 mm Hg is a key for successful adult living donor liver transplantation utilizing smaller grafts than before.

To prevent small-for-size syndrome in adult-to-adult living donor liver transplantation (A-LDLT), larger grafts (ie, right lobe grafts) have been selected in many transplant centers. However, some centers are investigating the benefits of portal pressure modulation. Five hundred sixty-six A-LDLT procedures using right or left lobe grafts were performed between 1998 and 2008. In 2006, we introduced intentional portal pressure control, and we changed the graft selection criteria to include a graft/recipient weight ratio >0.7% instead of the original value of >0.8%. All recipients were divided into period I (1998-2006, the era of unintentional portal pressure control; n = 432) and period II (2006-2008, the era of intentional portal pressure control; n = 134). The selection of small-for-size grafts increased from 7.8% to 23.9%, and the selection of left lobe grafts increased from 4.9% to 32.1%. Despite the increase in the number of smaller grafts in period II, 1-year patient survival was significantly improved (87.9% versus 76.2%). In 129 recipients in period II, portal pressure was monitored. Patients with a portal pressure <15 mm Hg demonstrated better 2-year survival (n = 86, 93.0%) than patients with a portal pressure >or=15 mm Hg (n = 43, 66.3%). The recovery from hyperbilirubinemia and coagulopathy after transplantation was significantly better in patients with a portal pressure <15 mm Hg. In conclusion, our strategy for A-LDLT has changed from larger graft-based A-LDLT to controlled portal pressure-based A-LDLT with smaller grafts. A portal pressure <15 mm Hg seems to be a key for successful A-LDLT.

Ogura Y ，Hori T ，El Moghazy WM ，Yoshizawa A ，Oike F ，Mori A ，Kaido T ，Takada Y ，Uemoto S ... -  《-》