Background: Substantial interest has developed in the physiologic and therapeutic role of nitric oxide in the last few years. In patients with pulmonary hypertension it appears to be a useful selective pulmonary vasodilator; however, many issues of both staff and patient safety remained unanswered.
Methods: This study examines further safety issues and also presents preliminary clinical experience in patients after orthotopic heart transplantation with pulmonary hypertension and right-sided ventricular failure.
Results: Atmospheric levels of nitric oxide and nitrogen dioxide are 100 times less than occupational health standards. When nitric oxide is used at 70 parts per million in the presence of a fraction of inspired oxygen greater than 0.60, nitrogen dioxide levels in the circuit exceed the published short-term exposure limit of the American Conference of Government Industrial Hygienist of 5 parts per million.
Conclusion: Staff safety appears confirmed, but despite encouraging clinical results, further longer term safety and efficacy studies are indicated.