Portosystemic Shunts for "Too Small-for-Size Syndrome" After Liver Transplantation: A Systematic Review

Portosystemic shunts (PSSs) modulate the portal hyperperfusion against small-for-size syndrome (SFSS) after split or living donor liver transplantation. To find out the results and the limitations of PSSs against SFSS. We searched PubMed and Cochrane databanks for systematic review and analyzed the indications, types, morbidities, and survivals of the PSSs at split or living donor liver transplantations. Total 66 patients were assessed in 16 studies. Main indications for PSS were graft recipient weight ratio (GRWRs) < 0.8 % and/or portal vein pressure > 20 mmHg. Five different types of PSSs were described but hemi-portocaval shunts were the most common one. The incidence of SFSS was 12 %. Overall 90-day, 1-, and 3-year graft survivals were 80, 70, and 47 %, respectively. GRWR < 0.65 % was found as the only significant parameter on graft survival. The 90-day, 1- and 3-year graft survivals for GRWR < 0.65 and a parts per thousand yen0.65 % patients were 62.5, 42.8, and 30.0 and 95, 94, and 67 %, respectively (p = 0.03, p = 0.01, and p = 0.18). PSSs can modulate the small graft size (GRWR < 0.8 %) and/or portal hypertension (> 20 mmHg) after split or living donor liver transplantations sufficiently. However, its protective effect is not unlimited. If the GRWR is below 0.65 %, survival decreases significantly despite PSSs.