Inhaled nitric oxide differentiates pulmonary vasospasm from vascular obstruction after surgery for congenital heart disease.
OBJECTIVE
To evaluate whether a trial of inhaled nitric oxide (NO) differentiates reversible pulmonary vasoconstriction from fixed anatomic obstruction to pulmonary blood flow after surgery for congenital heart disease in patients at risk for pulmonary hypertension.


METHODS
Prospective cohort study.


METHODS
Tertiary care children's hospital.


METHODS
15 neonate and infants with elevated pulmonary artery or right ventricular pressure or with clinical signs suggestive of high pulmonary vascular resistance in the early postoperative period following repair of congenital heart disease.


METHODS
30-min trial of 40 ppm inhaled NO.


RESULTS
5 patients responded to inhaled NO, 2 patients were weaned from extracorporeal support with NO. Four were maintained on continuous inhaled NO for 3 to 5 days. All the responders survived. Ten patients did not respond to NO. An important anatomic obstruction was found with echocardiography or angiography in all 10 patients. Reintervention was performed in 6/10 (4 stent placement, 1 balloon angioplasty of pulmonary arteries and 1 revision of systemic to pulmonary shunt). Six of the nonresponders died.


CONCLUSIONS
A trial of inhaled NO after cardiac surgery in neonates and infants may be useful to differentiate reversible pulmonary vasoconstriction from fixed anatomic obstruction and may provide useful information if temporary support with extracorporeal membrane oxygenation is considered. Failure to respond to inhaled NO should prompt further investigations to rule out a residual obstruction.
Beghetti
M
M
Division of Cardiology, Department of Critical Care Medicine and Pediatrics, Hospital for Sick Children and University of Toronto, Canada.
Morris
K
K
Cox
P
P
Bohn
D
D
Adatia
I
I
D000280:Administration, Inhalation; D000792:Angiography; D000800:Angioplasty, Balloon; D003251:Constriction, Pathologic / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D003937:Diagnosis, Differential; D004452:Echocardiography; D015199:Extracorporeal Membrane Oxygenation; D005260:Female; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009569:Nitric Oxide / Q000008:administration & dosage; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D011446:Prospective Studies; D011651:Pulmonary Artery; D011652:Pulmonary Circulation; D012307:Risk Factors; D015607:Stents; D014665:Vasodilator Agents / Q000008:administration & dosage
D014665:Vasodilator Agents; D009569:Nitric Oxide