Rate of surfactant administration influences lung function and gas exchange in a surfactant-deficient rabbit model

Abstract

The aim of this study was to test whether the effect of surfactant treatment on lung function in a surfactant‐deficient animal model can be influenced by the rate at which surfactant is administered. Surfactant deficiency was induced in 18 New Zealand white rabbits (weighing approx. 1 kg each) by lung lavage with normal saline. The arterial/alveolar oxygen ratio (a/A ratio), functional residual capacity (FRC), dynamic compliance of the respiratory system (Crs), tidal volume (VT), alveolar portion of the tidal volume (VA) and arterial PCO2 (Pa,CO2) were measured before and after lavage and 15, 30, 60, 90, and 120 min after administration of a single dose of surfactant (Survanta®, 100 mg/kg). Two surfactant administration protocols were compared over a 2‐h interval: an infusion lasting 4 min and an infusion over 2 min. Both administrations were given during continuous mechanical ventilation. The six lung function and gas exchange parameters improved significantly following surfactant administration over 2 min compared with a control group. However, only the a/A ratio and VA improved following the 4‐min protocol. Comparison of the two intervention protocols yielded significantly differences in VA and Pa,CO2, favoring the shorter administration. These results support the hypothesis that fast (2 min) administration of surfactant will improve its distribution to formerly collapsed alveoli and results in better lung function, improved ventilation, and (to a lesser extent) better oxygenation than prolonged infusions (4 min). Pediatr. Pulmonol. 1998; 25:196–204. © 1998 Wiley‐Liss, Inc.

High frequency oscillation ventilation compared to conventional mechanical ventilation plus exogenous surfactant replacement in rabbits

“…Estudos similares em animais têm utilizado uma dose entre 50 a 100 mg/ kg 14,15,[24][25][26] . Dentro de boas condições o surfactante exó-geno tem uma meia vida estimada em torno de 5 horas 24,27 .…”

“…Entretanto, o uso de surfactante exó-geno em séries clínicas de pacientes com SARA tem apresentado resultados controversos 18,24,25 . Esses diferentes resultados podem ser atribuídos aos seguintes fatores: a) tipo e origem do surfactante utilizado; b) método de administração do surfactante; c) dose e fase da doença em que o surfactante foi administrado; d) presença de proteínas inibidoras na via aérea terminal; e d) estratégia ventilatória utilizada concomitante com a administração de surfactante 14,15,24,26 .…”

Molecular Pathogenesis of Fibrosis, Thrombosis and Surfactant Dysfunction in the Lungs of Severe COVID-19 Patients

“…This enables efficient lung inflation and deflation while preventing the small airways from collapsing. Moreover, the effectiveness of this gas exchange can be significantly influenced by changes in the amount, composition, and structure of the surfactant, since the exchange of oxygen and carbon dioxide between the air space and the lung parenchyma takes place through the surfactant layer at the air–liquid interface [ 24 , 25 , 26 , 27 , 28 , 29 ].…”

Intrapulmonary application of a 5‐lipoxygenase inhibitor using surfactant as a carrier reduces lung edema in a piglet model of airway lavage

“…All animals in the two intervention groups received 96 mg/kg (4 ml/kg) Curosurf TM (Nycomed, Unterschleißheim, Germany) plus 1 ml/kg DMSO, equivalent to a total volume of 5 ml/kg, within 2 min. 20 In intervention group 2 (S þ MK), 3 mg/kg MK886 were dissolved in DMSO before admixture with the surfactant.…”