Background/aims: Long-term positive end-expiratory pressure (PEEP) ventilation, particular with PEEP up to 15 mbar may impair graft-function in liver transplant (LT) patients. The aim of our study was to evaluate the impact of long-term high PEEP (at least 48 hours) on liver graft function. We retrospectively reviewed the records of 50 patients, who required artificial ventilation for at least 1 week with a PEEP level > or = 10mbar due to pulmonary complication caused mainly by sepsis (n = 19), pneumonia (n = 7) and lung edema associated with reperfusion syndrome or primary non-function of the graft (n = 13). Patients who required a PEEP > or = 10mbar within the first two days after transplantation (group A, n = 23) showed significant decrease of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin on day 3 and day 7 after initiation of high PEEP, whereas prothrombin time (PT) significantly increased on day 7. Group B (patients ventilated with PEEP > or = 10mbar after more than 2 days after transplantation, n = 27) showed a significant decrease of bilirubine and a significantly increase of PT on day 7., Conclusion: Long-term ventilation with PEEP levels of at least 10mbar does not harm graft function in patients following LT.