title: Polyethylene glycol addition does not improve exogenous surfactant function in an experimental model of meconium aspiration syndrome.
abstract: Meconium (MEC) is a potent inactivator of pulmonary surfactant. The authors studied the effects of polyethylene glycol addition to the exogenous surfactant over the lung mechanics and volumes. Human meconium was administrated to newborn rabbits. Animals were ventilated for 20 minutes and dynamic compliance, ventilatory pressure, and tidal volume were recorded. Animals were randomized into 3 study groups: MEC group (without surfactant therapy); S100 group (100 mg/kg surfactant); and PEG group (100 mg/kg porcine surfactant plus 5% PEG). After ventilation, a pulmonary pressure-volume curve was built. Histological analysis was carried out to calculate the mean alveolar size (Lm) and the distortion index (DI). Both groups treated with surfactant showed higher values of dynamic pulmonary compliance and lower ventilatory pressure, compared with the MEC group (P < .05). S100 group had a larger maximum lung volume, V(30), compared with the MEC group (P < .05). Lm and DI values were smaller in the groups treated with surfactant than in the MEC group (P < .05). No differences were observed between the S100 and PEG groups. Animals treated with surfactant showed significant improvement in pulmonary function as compared to nontreated animals. PEG added to exogenous surfactant did not improve lung mechanics or volumes.
authors.affiliation: Department of Pediatrics, São Paulo State University, Rubiao Junior, Campus Botucatu, Botucatu, Brazil. jc.lyra@uol.com.br
authors.forename: Joao Cesar
authors.initials: JC
authors.lastname: Lyra
authors.forename: Renata Suman
authors.initials: RS
authors.lastname: Mascaretti
authors.forename: Alexander Roberto
authors.initials: AR
authors.lastname: Precioso
authors.forename: Luciana Branco
authors.initials: LB
authors.lastname: Haddad
authors.forename: Thais
authors.initials: T
authors.lastname: Mauad
authors.forename: Flavio A Costa
authors.initials: FA
authors.lastname: Vaz
authors.forename: Celso Moura
authors.initials: CM
authors.lastname: Rebello
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D004338:Drug Combinations; D006801:Humans; D007231:Infant, Newborn; D007442:Intubation, Intratracheal; D008168:Lung / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D008170:Lung Compliance / Q000187:drug effects / Q000502:physiology; D008471:Meconium Aspiration Syndrome / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011663:Pulmonary Surfactants / Q000494:pharmacology*; D011817:Rabbits; D012121:Respiration, Artificial; D015656:Respiratory Mechanics / Q000187:drug effects* / Q000502:physiology
chemical_list: D004338:Drug Combinations; D011663:Pulmonary Surfactants; D011092:Polyethylene Glycols