A prospective, randomized, crossover pilot study of inhaled nitric oxide versus
inhaled prostacyclin in heart transplant and lung transplant recipients.
Author(s): Khan TA(1), Schnickel G, Ross D, Bastani S, Laks H, Esmailian F, Marelli D,
Beygui R, Shemin R, Watson L, Vartapetian I, Ardehali A.
Affiliation(s): Author information:
(1)Division of Cardiothoracic Surgery, Department of Surgery, UCLA School of
Medicine, Los Angeles, CA 90095-1741, USA.
Publication date & source: 2009, J Thorac Cardiovasc Surg. , 138(6):1417-24
OBJECTIVE: Inhaled nitric oxide has been shown to reduce pulmonary vascular
resistance in patients undergoing cardiothoracic surgery, but it is limited by
toxicity, the need for special monitoring, and cost. Inhaled prostacyclin also
decreases pulmonary artery pressure, is relatively free of toxicity, requires no
specific monitoring, and is less expensive. The objective of this study was to
compare nitric oxide and prostacyclin in the treatment of pulmonary hypertension,
refractory hypoxemia, and right ventricular dysfunction in thoracic transplant
recipients in a prospective, randomized, crossover pilot trial.
METHODS: Heart transplant and lung transplant recipients were randomized to
nitric oxide or prostacyclin as initial treatment, followed by a crossover to the
other agent after 6 hours. Pulmonary vasodilators were initiated in the operating
room for pulmonary hypertension, refractory hypoxemia, or right ventricular
dysfunction. Nitric oxide was administered at 20 ppm, and prostacyclin was
administered at 20,000 ng/mL. Hemodynamic and oxygenation parameters were
recorded before and after initiation of pulmonary vasodilator therapy. At 6
hours, the hemodynamic and oxygenation parameters were recorded again, just
before discontinuing the initial agent. Crossover baseline parameters were
measured 30 minutes after the initial agent had been stopped. The crossover agent
was then started, and the hemodynamic and oxygenation parameters were measured
again 30 minutes later.
RESULTS: Heart transplant and lung transplant recipients (n = 25) were randomized
by initial treatment (nitric oxide, n = 14; prostacyclin, n = 11). Nitric oxide
and prostacyclin both reduced pulmonary artery pressure and central venous
pressure, and improved cardiac index and mixed venous oxygen saturation on
initiation of therapy. More importantly, at the 6-hour crossover trial, there
were no significant differences between nitric oxide and prostacyclin in the
reduction of pulmonary artery pressures or central venous pressure, or in
improvement in cardiac index or mixed venous oxygen saturation. Nitric oxide and
prostacyclin did not affect the oxygenation index or systemic blood pressure.
There were no complications associated with nitric oxide or prostacyclin.
CONCLUSION: In heart transplant and lung transplant recipients, nitric oxide and
prostacyclin similarly reduce pulmonary artery pressures and central venous
pressure, and improve cardiac index and mixed venous oxygen saturation. Inhaled
prostacyclin may offer an alternative to nitric oxide in the treatment of
pulmonary hypertension in thoracic transplantation.
|