Effects of positive end-expiratory pressure on hemodynamics and indocyanine green kinetics in patients after orthotopic liver transplantation

Objective: To determine the impact of positive end-expiratory pressure (PEE P) Ventilation on hemodynamics and a clinical test for assessment of dynami c liver performance in patients undergoing orthotopic liver transplantation (OLT). Design: Prospective, descriptive patient study, Setting: University hospital intensive care unit. Patients: A total of 25 patients after OLT. Interventions: All patients were intubated and mechanically ventilated with biphasic positive airway pressure. The effects of three different randomly chosen levels of PEEP (0 cm H2O, 5 cm H2O, and 10 cm H2O) were studied in the immediate postoperative period. Measurements and Main Results: Systemic hemodynamics, arterial and venous b lood gas analyses, and plasma disappearance rate of indocyanine green (ICG, ,,), using the transpulmonary indicator dilution technique, were obtained s imultaneously. For data evaluation, patients were grouped retrospectively a ccording to their hemodynamic response to PEEP (Group A and Group B). In Gr oup A (n = 13), PEEP did not alter cardiac index, In Group B (0 = 11), PEEP levels of 5 cm H2O and 10 cm H2O significantly reduced cardiac index and o xygen delivery. ICG(PDR) remained statistically unchanged in both groups. Conclusions: Short-term pressure-controlled ventilation with PEEP levels of up to 10 cm H2O does not exert detrimental effects on systemic hemodynamic s in OLT patients and does not interfere with ICG(PDR) However, it remains to be determined whether these findings could be confirmed under the applic ation of higher PEEP levels over a longer period of time and whether they c ould be of clinical relevance for the use of indocyanine green as a dynamic liver function test.