Prognostic implications of preoperative aerobic capacity and exercise oscillatory ventilation after liver...

Our aim was to determine preoperative aerobic capacity (oxygen uptake [V'O2 ]) and prevalence of exercise oscillatory ventilation (EOV), underlying clinical characteristics of patients with EOV, and significance of reduced aerobic capacity and EOV in predicting mortality after liver transplantation. We prospectively studied 263 patients who underwent elective liver transplantation. Patients were followed up for 1 year. Despite minor impairment of resting cardiopulmonary function, preoperative aerobic capacity was reduced (peak V'O2 : 64 ± 19% predicted). EOV occurred in 10% of patients. Model for End-Stage Liver Disease score tended to be higher in patients with EOV compared to patients without, but failed to reach significance (p = 0.09). EOV patients had lower peak V'O2 and higher ventilatory drive. EOV was more frequent in nonsurvivors than in survivors (30% vs. 9%, p = 0.01) and was independently associated with posttransplant all-cause 1-year mortality. Reduced peak V'O2 best predicted the primary composite endpoint defined as 1-year mortality and/or prolonged hospitalization and early in-hospital mortality. Multivariate analysis revealed EOV (χ(2), 3.96; p = 0.04) and V'O2 (χ(2), 4.28; p = 0.04) as independent predictors of mortality and so-called primary composite endpoint, respectively. EOV and reduced peak V'O2 may identify high-risk candidates for liver transplantation, which would motivate a more aggressive treatment when detected.