According to a study in the February edition of Liver Transplantation, a journal published by Wiley-Blackwell on behalf of the American Association for the Study of Liver Diseases, preoperative cardiopulmonary exercise testing (CPET) is a specific predictor of 90-day survival after liver transplantation. The findings reveal that the CPET measurement, the anaerobic threshold or fitness level, is an important predictor of mortality in patients following transplantation.

CPET is a non-invasive approach of measuring patients’ cardiorespiratory fitness and has already been utilized to predict morbidity and mortality after other major surgeries.

Dr. James Prentis from Freeman Hospital in Newcastle upon Tyne in the U.K. explains:

“Liver transplantation carries a significant mortality risk in the early days following surgery. An accurate preoperative assessment like CPET could help minimize patient mortality and optimize limited donor organs.”

In the new study, researchers included CPET over three years as part of the preoperative evaluation in 182 patients who underwent liver transplantation at Freeman Hospital. CPET was defined as the ability to determine the anaerobic threshold. Of all patients, 165 (91%) successfully completed the CPET, with follow-up after the transplantation to determine 90-day mortality, critical care and duration of hospital stay.

The findings revealed that from 60 patients (33%) who received a liver transplant, 6 patients (10%) died after the transplantation. The researchers established that the average anaerobic threshold was substantially higher in those who survived compared with those who died, and according to a multivariate analysis, cardiopulmonary reserve proved to be an important predictor of mortality.

In a concluding statement Dr. Prentis says:

“CPET is a non-invasive, sensitive and specific predictor of survival following liver transplantation. However, further evaluation of its predictive value in larger cohorts is necessary.”

In a related editorial also published in Liver Transplantation, Dr. James Findlay from the Mayo Clinic in Rochester, Minnesota writes:

“While CPET is widely available there are similar preoperative assessments such as the six-minute walking test that could also be used. Liver transplantation specialists have a duty to provide candidates with an accurate risk-benefit assessment and ensure that scarce donor organs are used effectively. The findings of Prentis and colleagues are striking enough to merit further evaluation.”

Dr. Findlay suggests large, multi-center investigations of CPET that include additional mortality indicators are necessary to develop an outcome model that could be widely used in evaluating candidates for liver transplantation.

Written by Petra Rattue