Inhaled Nitric Oxide Therapy After Fontan-Type Operations

Abstract

Purpose

Inhaled nitric oxide (NO) therapy is a newly developed strategy designed to reduce pulmonary vascular resistance after the Fontan-type operation. We reviewed our experience to evaluate its efficacy and true indications.

Methods

We retrospectively examined 47 children who received inhaled NO therapy after the Fontan-type operation between August 1996 and December 2002. The maximal dose of NO ranged from 5 to 30 ppm (median 10 ppm), and the duration of inhaled NO therapy ranged from 5 h to 52 days (median 2 days).

Results

Inhaled NO significantly decreased the central venous pressure (CVP), from 16.2 ± 2.2 to 14.6 ± 2.2 mmHg (P < 0.0001), and the transpulmonary pressure gradient between the CVP and left atrial pressure, from 9.9 ± 2.9 to 8.4 ± 2.7 mmHg (P < 0.0001). It also increased the systolic systemic arterial pressure from 71.9 ± 15.2 to 76.8 ± 14.5 mmHg (P < 0.05). In 26 patients with additional fenestration, inhaled NO led to a significant improvement in SaO₂ from 90.1% ± 9.6% to 93.3% ± 7.9% (P < 0.01). However, patients with a CVP <15 mmHg or a transpulmonary pressure gradient <8 mmHg, or both, after the Fontan-type operation, showed no significant changes in hemodynamics during inhaled NO therapy.

Conclusions

We propose that a CVP ≥15 mmHg or a transpulmonary pressure gradient ≥8 mmHg, or both, after Fontan-type operations are appropriate indications for inhaled NO therapy.