Effect of pre-transplant sarcopenia on the estimation of standard liver volume in living-donor liver transplant candidates: risk factor for post-transplant small-for-size syndrome? A retrospective study

The aim of the present study was to investigate whether LT candidates with sarcopenia are at an increased risk of receiving an inappropriate standard liver volume (SLV) estimation by standard body weight (BW)-derived SLV formula. Non-BW-SLV estimation formulas were tested in 262 LDLT donors and compared to a standard BW-SLV formula. The anthropometric parameters used were the thoracic width (TW-SLV) and thoracoabdominal circumference (TAC-SLV). Subsequently, sarcopenic and non-sarcopenic LDLT candidates (total, 217 patients) were compared in terms of estimated BW-SLV (routine method) and non-BW-SLV. In donors, TW-SLV showed comparable concordance with CT scan measured total liver volume as BW-SLV. The performance of TAC-SLV was low. In recipients, the prevalence of pre-LT sarcopenia was 30.4%. Sarcopenic patients were attributed a significantly lower BW-SLV than non-sarcopenic (sarcopenia vs no-sarcopenia, 1063.8 ml [1004.1–1118.4] vs. 1220.7 ml [1115.0–1306.6], P < 0.001), despite comparable TW-SLV, age, body height, and gender prevalence. As a result, sarcopenic patients received a graft with a statistically lower weight at organ procurement and developed more frequently a small-for-size syndrome (SFSS) according to the Dahm et al. (27.7% vs. 6.8%, P < 0.01) and Kyushu (28.7% vs. 9.2%, P < 0.01) definition. Therefore, In sarcopenic patients, BW-SLV formulas are affected by an high risk of SLV underestimation, thus exposing them to an increased risk of post-LT SFSS.