Risks of Living Donor Liver Transplantation Using Small-For-Size Grafts

The role of graft to recipient weight ratio on enhanced recovery of the recipient after living donor liver transplantation – A systematic review of the literature and expert panel recommendations

“…There was a lack of standardization with regards to patient groups, recipient illness severity, stratification of portal inflow modulation done at recipient operation, and follow‐up interval/time across the available single‐center reports. In light of this, short and long‐term survivals were noted to be similar in the majority of studies reporting this outcome measure and comparing low GRWR (< .8%) groups to those with ≥ .8% 5,6,8–12,14–18 . Differences in outcomes were noted, however, in studies reporting survival data and comparing two or more groups with GRWR < .8% in order to evaluate the impact of portal inflow modulation 2,17 .…”

“…Other complications such as intrabdominal bleeding, biliary complications, rejection, and relaparotomy rates have been noted to be similar between patients with lower GWRW (< .8%) as compared to those above this threshold, and for groups with and without portal inflow modulation. 1,5,[16][17][18]31 Of note, two studies did report a significantly increased risk of hepatic artery thrombosis in small grafts with GRWR < .8%, which may in part be secondary to the hepatic arterial buffer response that may lead to attenuation of hepatic arterial flow in high portal flow grafts. 9,16 Intensive care unit and hospital length of stay are important surrogates for resource utilization and are thus important considerations for evaluating the potential for enhanced recovery.…”

“…It has been suggested that low GRWR may impact graft survival, however, heterogeneity in defining a threshold for "low" persists with an arbitrary value of < .8% being commonly used in the literature. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Other metrics of graft size have been used in lieu of GRWR, including an absolute graft weight of 650 g, which has been shown to have a positive predictive value of 94% for survival 19 as well as percentage of the recipients standard liver volume (with an aim for greater than 40%). 20,21 Relatively smaller grafts that are unable to meet metabolic and synthetic demands of the transplant recipient may result in the small-forsize-syndrome (SFSS).…”

“…Graft size and graft‐to‐recipient weight ratio (GRWR) are considered critical factors in the assessment of a potential living donor‐recipient pair. It has been suggested that low GRWR may impact graft survival, however, heterogeneity in defining a threshold for “low” persists with an arbitrary value of < .8% being commonly used in the literature 1–18 . Other metrics of graft size have been used in lieu of GRWR, including an absolute graft weight of 650 g, which has been shown to have a positive predictive value of 94% for survival 19 as well as percentage of the recipients standard liver volume (with an aim for greater than 40%) 20,21 …”

“…In light of this, short and long-term survivals were noted to be similar in the majority of studies reporting this outcome measure and comparing low GRWR (< .8%) groups to those with ≥ .8%. 5,6,[8][9][10][11][12][14][15][16][17][18] Differences in outcomes were noted, however, in studies reporting survival data and comparing two or more groups with GRWR < .8% in order to evaluate the impact of portal inflow modulation. 2,17 In these reports, groups with low GRWR and portal inflow modulation had significantly higher recipient and/or graft survival.…”