Primary graft failure (
PGF) is one of the major complications that occurs immediately following
lung transplantation and greatly contributes to increased morbidity and mortality. The incidence of
PGF is correlated with a marked decline in endogenous
nitric oxide (NO) and cyclic
guanosine monophosphate (cGMP) levels. Therefore, the administration of NO during
lung transplantation has been proposed as a possible therapeutic treatment to prevent or attenuate
PGF pathogenesis. Despite the initial positive results of experimental and uncontrolled clinical trials, recent randomized clinical trials do not support the prophylactic administration of inhaled
nitric oxide (iNO) for the prevention of
PGF following
lung transplantation under the conditions tested. Nonetheless, there is evidence that iNO administration during
PGF can improve oxygenation and reduce
pulmonary hypertension without altering systemic vascular resistance. This suggests that iNO may prevent the need for
extracorporeal membrane oxygenation (ECMO) during the hypoxic phase of
PGF. During the intraoperative phase of
transplantation,
one-lung ventilation (OLV) and pulmonary artery clamping usually increase PVR, causing decreased right ventricular function and hemodynamic instability. The administration of iNO during these lung transplant procedures could decrease
right ventricular dysfunction by reducing PVR and help to avoid the use of
cardiopulmonary bypass.