[Influence of pulmonary recruitment on exogenous surfactant effects].
An experimental model was devised to study the effects of a sustained insufflation maneuver on the immediate response to exogenous surfactant administration and the effects of baseline pulmonary volume subsequently used in 20 adult albino rats. Lung-injury was induced by repeated lavages with saline solution. Gas exchange, hemodynamic status, lung mechanics and histopathology were assessed. The rats were divided into four experimental groups. Group 1 was delivered 30 cm H2O sustained insufflation over 15 seconds prior to the surfactant. It was subsequently ventilated at positive end-expiratory pressure (PEEP) of 10 cm H2O. Group 2 did not receive sustained insufflation and was ventilated at PEEP of 10 cm H2O. Group 3 was delivered sustained insufflation and was ventilated with PEEP of 4 cm H2O; and group 4 did not receive sustained insufflation and was ventilated with PEEP of 4 cm H2O. The surfactant immediate effect was not modified by previous sustained insufflation administration. Increased PaO2 associated to high functional residual capacity (FRC) (Group 1 p = 0.0001; Group 2 p = 0.0001), regardless of sustained insufflation, was observed. The use of sustained insufflation prior to surfactant administration along with high FRC ventilation was associated with polymorphonuclear infiltrates beneath the bronchiolar epithelium (p = 0.008). Our results do not advocate the use of sustained insufflation prior to the administration of exogenous surfactant.
Servicio de Neonatología, Unidad de Medicina y Cirugía Experimental, Instituto Universitario Italiano de Rosario, Hospital Italiano Garibaldi, Rosario, Argentina. neonato@hig.org.ar
Nestor R
NR
Herrera
Roberto N
RN
Regnicoli
Mario Silvestre
MS
Begnis
Jose
J
Scrigna
Enzo
E
Peralta
Lisandro
L
Quadrelli
D000818:Animals; D005652:Functional Residual Capacity / Q000502:physiology; D007327:Insufflation; D008168:Lung / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D009504:Neutrophils / Q000502:physiology; D011175:Positive-Pressure Respiration; D011659:Pulmonary Gas Exchange; D011663:Pulmonary Surfactants / Q000008:administration & dosage*; D012123:Pulmonary Ventilation / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D012128:Respiratory Distress Syndrome / Q000188:drug therapy* / Q000503:physiopathology; D015656:Respiratory Mechanics / Q000187:drug effects* / Q000502:physiology
D011663:Pulmonary Surfactants