Response to first dose of inhaled albuterol in mechanically ventilated preterm infants

Background: Bronchodilator responses among preterm infants are heterogeneous. Bedside measurements may identify responders. Study design: Respiratory measurements (Resistance, Compliance, FiO₂) and pulse oximetry (SpO₂) patterns were downloaded from infants <30 weeks gestational age during the first 2 months of life. Mechanically ventilated infants who received albuterol were included (n = 33). Measurements were compared before and after first albuterol. Secondary analyses assessed subsequent doses. Results: Median gestation and birthweight were 25 3/7 weeks and 730 g, respectively. Mean Resistance decreased post-albuterol (p = 0.007). Sixty-eight percent of infants were responders based on decreased Resistance. Compliance and FiO₂ did not significantly differ. Percent time in hypoxemia (SpO₂< 85%) decreased post albuterol (p < 0.02). In responders, Resistance changes diminished with subsequent administration (all p = 0.01). Conclusions: Ventilator resistance decreased in two-thirds of preterm infants, consistent with studies that utilized formal pulmonary function testing. Albuterol had a variable effect on delivered FiO₂; however, hypoxemia may be useful in evaluating albuterol response.