The LiMAx test: a new liver function test for predicting postoperative outcome in liver surgery.

BACKGROUND: Liver failure has remained a major cause of mortality after hepatectomy, but it is difficult to predict preoperatively. This study describes the introduction into clinical practice of the new LiMAx test and provides an algorithm for its use in the clinical management of hepatic tumours.
METHODS: Patients with hepatic tumours and indications for hepatectomy were investigated perioperatively with the LiMAx test. In one patient, analysis of liver volume was carried out with preoperative three-dimensional virtual resection.
RESULTS: A total of 329 patients with hepatic tumours were evaluated for hepatectomy. Blinded preoperative LiMAx values were significantly higher before resection (n= 139; mean 351 microg/kg/h, range 285-451 microg/kg/h) than before refusal (n= 29; mean 299 microg/kg/h, range 223-376 microg/kg/h; P= 0.009). In-hospital mortality rates were 38.1% (8/21 patients), 10.5% (2/19 patients) and 1.0% (1/99 patients) for postoperative LiMAx of <80 microg/kg/h, 80-100 microg/kg/h and >100 microg/kg/h, respectively (P < 0.0001). A decision tree was developed to avoid critical values and its prospective preoperative application revealed a reduction in mortality from 9.4% to 3.4% (P= 0.019). DISCUSSION: The LiMAx test can validly determine liver function capacity and is feasible in every clinical situation. Combination with virtual resection could enable the calculation of residual liver function. The LiMAx decision tree algorithm for hepatectomy might significantly improve preoperative evaluation and postoperative outcome in liver surgery.