Heliox mixture improves gas exchange in ventilated low birth weight infants
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NEW YORK (Reuters Health) – Use of a helium/oxygen mixture can improve gas exchange and pulmonary mechanics in very low birth weight infants on long-term mechanical ventilation, new research shows.
Heliox has been shown to have beneficial effects on various pulmonary diseases in both adults and in children, according to the report in the June issue of Pediatrics. However, data regarding its use in neonates has been lacking, largely because suitable delivery devices have just recently become available.
The current investigation involved 10 preterm infants who had been on mechanical ventilation since birth, Dr. Claudio Migliori, from Spedali Civili Hospital, Brescia, Italy, and colleagues note. Resistive work of breathing, static compliance, pulmonary compliance, and respiratory rate were assessed before and after heliox treatment.
Infants who displayed a >20% drop in peak inspiratory pressure after 1 hour of heliox were extubated and switched to nasal bilevel positive airway pressure with heliox for 3 more hours. To keep oxygen saturation above 92% during this phase, the mean fraction of inspired oxygen was raised from 0.34 to 0.36.
With heliox use, mean peak inspiratory pressure fell from 21.4 to 17.4 cm H2O, work of breathing dropped from 0.46 to 0.22 joule/L, and transcutaneous pressure of CO2 decreased from 52.3 to 49.1 mm Hg. Moreover, mean transcutaneous pressure of O2 improved from 42.8 to 46.7 mm Hg, and minute ventilation from 332 to 478 mL/kg per minute.
Heliox treatment did not significantly affect mean airway pressure, respiratory rate, oxygen saturation, pulmonary compliance, and static compliance.
Eight subjects were extubated, although one required reintubation after 5 hours, the authors note.
“This study must be interpreted with caution because of the limitations related to lack of a control group and a blind design. However, our results suggest that heliox reduces work of breathing and the need for pressure support, and improves gas exchange in preterm mechanically ventilated infants,” the authors conclude.