Defining Surgical Difficulty During Open Right Lobe Donor Hepatectomy and its Prediction Using Preoperative Donor Computed Tomography Morphometry

Abstract

BackgroundThere is no accepted way to define difficult donor hepatectomy (DiffDH) during open right living donor hepatectomy (ORLDH). There are also no studies exploring association between DiffDH and early donor outcomes or reliable pre-operative predictors of DiffDH. MethodsConsecutive ORLDH performed over 18 months at a single center were included. Intra-operative parameters were used to develop an objective definition of DiffDH. The impact of DiffDH on early postoperative outcomes and achievement of textbook outcome (TO) was evaluated. Donor morphometry data on axial and coronal sections of donor CT at the level of portal bifurcation were collected. Donor and graft factors predictive of DiffDH were evaluated using univariate and multivariate logistic regression. ResultsOne hundred and eleven donors (Male-40.5%, Age-34± 9.5 years) underwent ORLDH during the study period. Difficulty score was constructed using five intra-operative parameters i.e. operating time, transection time, estimated blood loss, need for intra-operative vasopressors and need for Pringle maneuver. Donors were classified as DiffDH (score ≥ 2) or Standard DH (score<2). Twenty nine donors (26%) were classified as DiffDH. DiffDH donors suffered greater all cause morbidity (p=0.004) but not major morbidity (Clavien-Dindo score>2; p=0.651), more peri-operative transfusion (p=0.013), increased post-operative SIRS (p=0.034), delay in achieving full oral diet (p=0.047) and a 70% reduced chance of achieving TO as compared to StDH (p=0.007). On logistic regression analysis, increasing right lobe antero-posterior depth (RLdepth) was identified as an independent predictor of DiffDH (Odds ratio- 2.0(95% ci =1.2,3.3), p<0.006). ROC curve analysis identified RLdepth>14 cms as the best predictor of DiffDH (Sensitivity-79%, specificity-66%, Area under curve=0.803, p<0.001). ConclusionWe report a novel definition of DiffDH and show that it is associated with worse post-operative outcomes, including a lesser chance of achieving TO. We also report that DiffDH can be predicted from readily available donor CT parameters.