Is an intraoperative liver function assessment possible? Application of the C-methacetin-breath-test during major liver resections - a pilot study.

Background: As prevention of posthepatectomy-liver-failure is crucial, there is need of dynamic assessment of liver function, even intraoperatively. C-methacetin-breath-test estimates the organ's microsomal functional capacity. This is its first intraoperative evaluation in major liver surgery.

Methods: 30 patients planed for resection of ≥3 liver segments, between March-November 2019, were prospectively enrolled in this "single-center", pilot study. Using the C-methacetin-breath-test, liver function was assessed four times: preoperatively, intraoperatively before and after resection and postoperatively. The resulted maximum-liver-function-capacity (LiMAx)-values and delta-over-baseline (DOB)-curves were compared, further analyzed and correlated to respective liver volumes.

Results: The intraoperative LiMAx-values before resection were mostly lower than the preoperative ones (-11.3% ± 28%). The intraoperative measurements after resection resulted to mostly higher values than the postoperative ones (42.35% ± 46.19%). Pharmacokinetically, an interference between the two intraoperative tests was observed. There was no strong correlation between residual liver volume and function with a percentual residual-LiMAx mostly lower than the percentual residual volume (-17.7% ± 4.1%).

Conclusions: Intraoperative application of the C-methacetin-breath-test during major liver resections seems to deliver lower values than the standard preoperative test. As multiple intraoperative tests interfere significantly to each other, a single intraoperative measurement is suggested. Multicentric standardized measurements could define the "normal" range for intraoperative measurements and control their predictive value.