Nasal-airway pressure release ventilation (NASAL-APRV) and nasal-continuous positive airway pressure (NASAL-CPAP): hemodynamic, respiratory and gasometric effects

This study compared the NASAL-CPAP to a new mode called NASAL-APRV as a non-invasive weaning procedure from mechanical ventilation using nasal prongs, analysing the hemodynamic, respiratory and gasometric effects.

Data were collected in a randomized and prospective protocol, applied to pediatric patients (minimum age, 10 days; maximum age, 10 years 6 months; mean age, 1 year 8 months 12 days), totalling n = 17 cases. For each patient the mean airway pressure was kept constant for both modes of ventilation, 4.5 ± 0.65 cmH₂O. In NASAL-APRV the maximum distension pressure ranged from 5 to 8 cmH₂O and the release pressure was always to 0 cmH₂O; release time was 1.0s and release frequency of 15 rpm. NASAL-CPAP was kept between 3 to 5 cmH₂O. FiO₂ was 40%. Statistical analysis: Wilcoxon signed-rank test.

Conclusions

In the hemodynamic effects there was a significant alteration only in heart rate, lowering in the NASAL-APRV. In the respiratory and gasometric changes there is a significant alteration towards improval both in oxygenation and ventilation, achieved with a better respiratory comfort.

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