[Perioperative nitric oxide inhalation therapy for open heart surgery patients with pulmonary hypertension]

To investigate effectiveness and safety of perioperative nitric oxide (NO) inhalation therapy for open heart surgery patients with pulmonary hypertension.

Servo 300A and Pulmonox Aeronox were used for NO delivery and monitoring. NO was used perioperatively in 27 adult and 1 pediatric open heart surgery patients with pulmonary hypertension which were not effectively relieved by conventional treatment. At the beginning of NO inhalation therapy, the dose of NO was (5-10) x 10(-6), and mildly elevated to 20 x 10(-6). Pulmonary arterial pressure (PAP), arterial pressure (AP), pulmonary vascular resistance (PVR) and oxygenation index (PaO(2)/FiO(2)) of patients were monitored before and after treatment. Criterion for NO responsiveness was: AP/PAP or PaO(2)/FiO(2) improved more than 20% within 1 hour. NO inhalation therapy was discontinued if there was no response within 1.5 hours.

Responsive rate in these adult patients was 77.8% (21/27 cases). Duration of NO therapy was 12-96 (32.6+/-10.3) hours. One 4-year-old atrial septal defect child with medium severity of pulmonary artery hypertension showed deterioration of pulmonary hypertension with serious hypoxemia [PaO(2)/FiO(2)=40 mm Hg (1 mm Hg=0.133 kPa), fractional concentration of inspired oxygen (FiO(2)) was 1.00] post operatively. NO inhalation therapy showed a very marked response and effect. The child was weaned from mechanical ventilation in four days. No adverse event was detected in patients and caregivers during and after NO inhalation therapy.

NO inhalation therapy is effective in cardiac surgery patients with deteriorating pulmonary artery hypertension perioperatively. Further clinical investigation is urgently needed for promoting it to become a clinical routinely available therapy.