Modified Bovine Surfactant Preparations in the Rat Lung Lavage Model

Background: In order to improve biological activity of natural bovine surfactant, we supplemented a commercially available preparation (SF-RII, Alveofact®) with different lipids resp. proteins .Materials and methods: SF-RII was supplemented with 11% phosphatidylglycerol (prep.1), 13% sphingomyelin (prep.2), 7.5% phosphatidylethanolamin-plasmalogen (prep.3), 7% phosphoethanolamin (prep.4) and 2% SP-B (prep.5). These surfactants were tested in the rat lung lavage model: animals were tracheotomized and mechanically ventilated (Babylog 1. Drägerwerk AG. FRG) at a rate of 36/minute, 26/6 cm H₂O pressure, FiO₂ 1.0; surfactant depletion was induced by saline lung lavage until paO₂ was < 100 mmHg. SF-RII 100 mg/kg b.w. was given intratracheally and compared with identical doses of the modified surfactant preparations(identical volumes) in 6 animals each with respect to oxygenation .Results: The table gives an overview:

Table 1

Conclusion: We were able to demonstrate a benefit with respect to biological activity only from supplementation with 13% sphingomyelin, other phospholipids decreased the biological activity, SP-B 2% did not change oxygenation.