title: Pulmonary mechanics and energetics in preterm infants who had respiratory distress syndrome treated with synthetic surfactant.
abstract: Pulmonary mechanics and energetics were determined in 32 neonates with respiratory distress syndrome, who were randomly assigned to receive treatment with an exogenous synthetic surfactant, Exosurf Neonatal, or air placebo. Pulmonary mechanics were measured before and 2 hours after surfactant (n = 13) or air placebo (n = 19) treatment, then longitudinally at 24, 48, and 72 hours after treatment, and again at 7, 14, and 28 days of age. There were no significant differences in the values for pulmonary mechanics or energetics 2 hours after the first dose of surfactant. Improvement in pulmonary mechanics was apparent 24 hours after surfactant treatment, when dynamic compliance was 36% greater than in the placebo group (p less than 0.03). Lung compliance values were also higher in surfactant-treated infants 48 and 72 hours after treatment, with a maximal increase of 64% at 7 days of age (p less than 0.03). Surfactant treatment also caused a significant decrease in total pulmonary resistance at 48 and 72 hours after initial treatment and at 14 days of age (p less than 0.04). Similarly, a decrease in flow-resistive work of breathing was demonstrated 24, 48, and 72 hours after surfactant treatment. At 28 days of age, pulmonary mechanics were not different in the two groups. We conclude that beneficial effects of surfactant on pulmonary mechanics were not apparent 2 hours after dosing but were evident 24 hours after dosing and persisted for the first 7 to 14 days of life.
authors.affiliation: Division of Neonatology, University of Pennsylvania, Philadelphia.
authors.forename: V K
authors.initials: VK
authors.lastname: Bhutani
authors.forename: S
authors.initials: S
authors.lastname: Abbasi
authors.forename: W A
authors.initials: WA
authors.lastname: Long
authors.forename: J S
authors.initials: JS
authors.lastname: Gerdes
mesh_terms: D004338:Drug Combinations; D005233:Fatty Alcohols / Q000627:therapeutic use*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D010767:Phosphorylcholine; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011446:Prospective Studies; D011663:Pulmonary Surfactants / Q000627:therapeutic use*; D012121:Respiration, Artificial; D012127:Respiratory Distress Syndrome, Newborn / Q000188:drug therapy* / Q000503:physiopathology*; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics / Q000187:drug effects*
chemical_list: D004338:Drug Combinations; D005233:Fatty Alcohols; D011663:Pulmonary Surfactants; D010767:Phosphorylcholine; D011092:Polyethylene Glycols; C047049:dipalmitoylphosphatidylcholine, hexadecanol, tyloxapol drug combination