《HighOxygenConcentrationsAdverselyAffectthePerformanceofPulmonarySurfactant.pdf》由会员分享，可在线阅读，更多相关《HighOxygenConcentrationsAdverselyAffectthePerformanceofPulmonarySurfactant.pdf（1页珍藏版）》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、作者：Craig D Smallwood,Parnian Boloori-Zadeh,Maricris R Silva and Andrew Gouldstone 摘要：BACKGROUND:Although effective in the neonatal population,exogenous pulmonary surfactant has not demonstrated a benefit in pediatric and adult subjects with hypoxic lung injury despite a sound physiologic rationale.I
2、mportantly,neonatal surfactant replacement therapy is administered in conjunction with low fractional FIO2 while pediatric/adult therapy is administered with high FIO2.We suspected a connection between FIO2 and surfactant performance.Therefore,we sought to assess a possible mechanism by which the ac
3、tivity of pulmonary surfactant is adversely affected by direct oxygen exposure in in vitro experiments.METHODS:The mechanical performance of pulmonary surfactant was evaluated using 2 methods.First,Langmuir-Wilhelmy balance was utilized to study the reduction in surface area(A)of surfactant to achie
4、ve a low bound value of surface tension after repeated compression and expansion cycles.Second,dynamic light scattering was utilized to measure the size of pulmonary surfactant particles in aqueous suspension.For both experiments,comparisons were made between surfactant exposed to 21%and 100%oxygen.
5、RESULTS:The A of surfactant was 21.1 2.0%and 35.8 2.0%during exposure to 21%and 100%oxygen,respectively(P=.02).Furthermore,dynamic light-scattering experiments revealed a micelle diameter of 336.0 12.5 m and 280.2 11.0 m in 21%and 100%oxygen,respectively(P .001),corresponding to a 16%decrease in mic
6、elle diameter following exposure to 100%oxygen.CONCLUSIONS:The characteristics of pulmonary surfactant were adversely affected by short-term exposure to oxygen.Specifically,surface tension studies revealed that short-term exposure of surfactant film to high concentrations of oxygen expedited the fra
7、ngibility of pulmonary surfactant,as shown with the A.This suggests that reductions in pulmonary compliance and associated adverse effects could begin to take effect in a very short period of time.If these findings can be demonstrated in vivo,a role for reduced FIO2 during exogenous surfactant delivery may have a clinical benefit.关键词：pulmonary surfactant,oxygen toxicity,infasurf,langmuir-wilhelmy,dynamic light scattering