Is Portal Inflow Modulation Always Necessary for Successful Utilization of Small Volume Living Donor Liver Grafts?

Abstract

Although the well‐accepted lower limit of the graft‐to‐recipient weight ratio (GRWR) for successful living donor liver transplantation (LDLT) remains 0.80%, many believe grafts with lower GRWR may suffice with portal inflow modulation (PIM), resulting in equally good recipient outcomes. This study was done to evaluate the outcomes of LDLT with small‐for‐size grafts (GRWR <0.80%). Of 1321 consecutive adult LDLTs from January 2012 to December 2017, 287 (21.7%) had GRWR <0.80%. PIM was performed (hemiportocaval shunt [HPCS], n = 109; splenic artery ligation [SAL], n = 14) in 42.9% patients. No PIM was done if portal pressure (PP) in the dissection phase was <16 mm Hg. Mean age of the cohort was 49.3 ± 9.1 years. Median Model for End‐Stage Liver Disease score was 14, and the lowest GRWR was 0.54%. A total of 72 recipients had a GRWR <0.70%, of whom 58 underwent HPCS (1 of whom underwent HPCS + SAL) and 14 underwent no PIM, whereas 215 had GRWR between 0.70% and 0.79%, of whom 51 and 14 underwent HPCS and SAL, respectively. During the same period, 1034 had GRWR ≥0.80% and did not undergo PIM. Small‐for‐size syndrome developed in 2.8% patients. Three patients needed shunt closure at 1 and 4 weeks and 60 months. The 1‐year patient survival rates were comparable. In conclusion, with PIM protocol that optimizes postperfusion PP, low‐GRWR grafts can be used for appropriately selected LDLT recipients with acceptable outcomes.

Is Portal Inflow Modulation Always Necessary for Successful Utilization of Small Volume Living Donor Liver Grafts?

“…However, the lowest GRWR in the study by Soin et al (1) was 0.54% with no difference in mortality across low GRWR groups. Is a GRWR of 0.8%, thus, no longer a sacrosanct figure? If so, what GRWR should be truly low vis-à-vis recipient sickness and graft quality parameters?…”

“…We read with interest the article by Soin et al (1) The question posed in the article title is aptly answered by the fact that 69.77% of recipients with a graft-torecipient-weight ratio (GRWR) above 0.7% (85% of 0.75%-0.80% and 44.44% of 0.70%-0.74%) and nearly 19.44% of recipients with GRWR <0.7% did not need portal inflow modulation (PIM).…”

“…It would really be interesting to know about the outcomes in the left-sided grafts from the cohort of Soin et al (1) Kaido et al (3) in their study with a high number of left lobe grafts demonstrated that the lower limit of GRWR can be safely reduced to 0.6% using PIM.…”

“…The protocol of Soin et al (1) is based on actual graft weight with no mention of discordance, if any, in graft weight estimation, especially of grafts with a GRWR of <0.7%. As the authors suggest, HPCS is a more effective, modifiable, and predictable way of inflow modulation especially, more so, when GRWR is <0.7%, with a small but certain risk of portal steal.…”

“…Points of caution include sepsis as the most common cause of mortality in low GRWR grafts and small-for-size-syndrome (SFSS) despite modulation (4.1%). (1) sanjay Goja, F.A.C.s., F.e.B.s. Manish srivastava, M.B.B.s., M.s., d.N.B.…”