Inhaled nitric oxide therapy after Fontan-type operations

Area of Science:

• Pediatric Cardiology
• Cardiovascular Surgery
• Pulmonary Hypertension

Background:

• The Fontan-type operation is a complex surgical procedure for single-ventricle congenital heart defects.
• Pulmonary vascular resistance can remain elevated post-Fontan, leading to significant morbidity.
• Inhaled nitric oxide (NO) is a vasodilator explored to manage pulmonary hypertension.

Purpose of the Study:

• To evaluate the efficacy of inhaled nitric oxide (NO) therapy in reducing pulmonary vascular resistance after Fontan-type operations.
• To determine the appropriate clinical indications for inhaled NO therapy in this patient population.

Main Methods:

• Retrospective review of 47 children undergoing inhaled NO therapy post-Fontan-type operation (1996-2002).
• Doses of inhaled NO ranged from 5 to 30 ppm (median 10 ppm).
• Therapy duration varied from 5 hours to 52 days (median 2 days).

Main Results:

• Inhaled NO significantly decreased central venous pressure (CVP) and transpulmonary pressure gradient.
• Systolic systemic arterial pressure increased significantly with inhaled NO.
• Patients with fenestration showed improved oxygen saturation (SaO2) with inhaled NO.
• No significant hemodynamic changes were observed in patients with low CVP or transpulmonary pressure gradient.

Conclusions:

• Inhaled NO therapy is effective in improving hemodynamics in select pediatric patients post-Fontan-type operation.
• Appropriate indications for inhaled NO include a CVP ≥15 mmHg or a transpulmonary pressure gradient ≥8 mmHg.
• This therapy may help manage pulmonary vascular resistance and improve outcomes in this challenging patient group.