Background: There is no agreement to define the target FiO2 to adopt in the lung recruitment phase during HFOV in preterm infants. We report our experience of an optimal lung volume strategy (OLVS), defined as FiO2≤0.25 during the recruitment phase, in a cohort of neonates with gestational age (GA) ≤27 weeks treated with elective HFOV for respiratory distress syndrome (RDS) between July 2006 and September 2008.
Methods: FiO2 used during the recruitment phase was different according to physician' evaluation. 51 newborns were then divided into two groups: patients reaching FiO2≤0.25 (OLVS Group, N.=28), and patients reaching FiO2>0.25 (No-OLVS Group, N.=23).
Results: Prior to surfactant administration OLVS Group, respect to No-OLVS Group, received a significantly higher continuous distending pressure (CDP): 12.8±1.1 cmH2O vs 11.2±1.3 cmH2O (P<0.0001) and a significantly lower FiO2: 0.25±0.01 vs 0.35±0.06 (P<0.0001). A multivariate modeling approach confirmed that OLVS was significantly associated to the need for less surfactant doses (OR 0.19[95% CI 0.05-0.84]), a decreased risk of ductus arteriosus surgically ligated (OR 0.13[95% CI 0.02-0.86]) and to a lower number of ventilation hours before extubation: -152 (95% CI -284- -20).
Conclusion: OLVS to fully recruit the lungs achieving FiO2≤0.25 during elective HFOV is associated with better short-term pulmonary outcomes respect to a strategy where the patients received a FiO2>0.25 during the recruitment phase. Utilizing HFOV in this way provides a more effective means to recruit and protect acutely injured lungs.