Inhaled nitric oxide for lowering of pulmonary artery pressure after congenital heart surgery

Aim of the study: To evaluate the efficacy of inhaled nitric oxide (NO) for lowering of pulmonary artery pressure after congenital heart surgery. Patients and methods: Case series study in patients who were treated with inhaled NO after congenital heart surgery at the Heart Institute in 2022-2024. Inhaled nitric oxide was delivered by the NOxBOXi system at the initial dose of 10 ppm, maximal dose of 20 ppm and was weaned when the patient’s hemodynamic status was stable for at least 48 hours. Results: 27 patients, aged 1 month to 15 years, were treated with inhaled NO, including 18 patients with postoperative pulmonary hypertension (group 1), 5 patients with elevated pulmonary pressure after Glenn operation (group 2), and 4 patients with postoperative right ventricular failure (group 3). In all patients, there was a rapid and marked fall of pulmonary artery pressure and improvement of hemodynamic status after initiation of inhaled NO. In each group there was 1 death from severe heart failure. The remaining patients were weaned from inhaled NO after 2-20 days and spent 7-47 days in the intensive care unit. Conclusions: Inhaled NO has a high efficacy in lowering of pulmonary artery pressure after congenital heart surgery, making it a useful tool for the treatment of postoperative pulmonary hypertension and postoperative right ventricular failure, and for lowering of pulmonary artery pressure after Glenn operation.