High flow-mediated vasodilatation predicts pulmonary edema in liver transplant patients

Background: Early pulmonary edema is common after orthotopic liver transplantation. Associated pathogenic mechanisms might involve increased activity of cardiac-inhibitory systems due to increased vasodilator production, mainly nitric oxide (NO). NO is primarily responsible for flow-mediated vasodilatation (FMD).We investigated the incidence of pulmonary edema in liver transplant patients and its correlation with FMD. Methods: We prospectively evaluated traditional risk factors, Doppler echocardiographic findings, derived hemodynamic data, and brachial artery nitroglycerin-induced vasodilatation (NTD) and FMDwithin 1week prior to liver transplantation in 54 consecutive liver transplant patients with cirrhosis. Post-transplantation chest roentgenography was performed daily. In-hospital outcomes, transfusion volume of blood components, and hemodynamic data during surgery and at the intensive care unit were analyzed. Results: Twenty-nine patients (53.7%) developed radiological pulmonary edema within 1 week of transplantation. Diffuse-type interstitial and alveolar pulmonary edema constituted 13 cases (24.1%). Patients with pulmonary edema had higher pretransplantation Child-Turcotte-Pugh scores (p = 0.01), cardiac output (p = 0.03), FMD (p < 0.01), NTD (p = 0.01), and FMD/NTD ratio (p = 0.02). Although the total volume of intravenous fluid transfused was higher in the pulmonary edema group, the net fluid retention during surgery was statistically insignificant. The lengths of intensive care unit stay and hospitalization, aswell as mortality rates,were not different in these groups. Conclusions: The high incidence of pulmonary edema after living donor liver transplantation was associated with a high FMD and FMD/NTD ratio at pretransplantation. FMD is the only significant predictor associated with pulmonary edema. However, we observed no alteration in mortality rates.