title: A rapid and accurate new bedside test to assess maximal liver function: a case report.
abstract: BACKGROUND
  In liver surgery, appropriate preoperative evaluation and preparation of the patient is of cardinal importance. The up-to-date, preoperative prediction of residual liver function has thus far been limited. As post-hepatectomy liver failure is a major cause of mortality, a new and simple bedside test (LiMAx) has been developed to predict postoperative liver function in conjunction with preoperative volumetric analysis of the liver.
  
  
  METHODS
  A 45-year-old patient presented with a cecal carcinoma and a large synchronous liver metastasis for major liver surgery. Liver function was determined by the LiMAx-test for the enzymatic capacity of cytochrome P450 1A2, which is ubiquitously and solely active in the liver. A solution of 2 mg/kg body weight (13)C-labeled methacetin was injected as a bolus into an intravenous catheter and, thereafter, was metabolized into acetaminophen and (13)CO2 and pulmonarily exhaled. The analysis of the (13)CO2/(12)CO2 ratio was performed using online breath sampling over a period of maximally 60 minutes. Based on this test, a value of more than 315 μg/kg/h represents normal liver function. A laparoscopic right hemihepatectomy was planned during virtual resection with a residual liver volume of 48% and a preoperative anticipated residual LiMAx of 301 μg/kg/h. After successful resection, the initial postoperative LiMAx value was 316 μg/kg/h, indicating good liver function and a correct prediction of the outcome.
  
  
  CONCLUSIONS
  In the presented patient, residual liver function could be accurately predicted preoperatively using a combination of the new LiMax test with CT-volumetry. This test might significantly improve preoperative evaluation and postoperative outcomes in liver surgery.
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland ; Rorschacherstrasse 95, St.Gallen, 9007, Switzerland.
authors.forename: Sascha A
authors.initials: SA
authors.lastname: Müller
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Ignazio
authors.initials: I
authors.lastname: Tarantino
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Marcello
authors.initials: M
authors.lastname: Corazza
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Frank
authors.initials: F
authors.lastname: Pianka
authors.affiliation: Institute of Radiology, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Fornaro
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Beutner
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Lüthi
authors.affiliation: Department of Surgery, Kantonsspital St.Gallen, St.Gallen, Switzerland.
authors.forename: Bruno M
authors.initials: BM
authors.lastname: Schmied
keywords: LiMAx; Liver function; Liver function measurement; Liver resection; Liver volumetry