Chung E H, Ko S Y, Kim I Y, Chang Y S, Park W S
Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul, Korea.
J Korean Med Sci. 2001 Feb;16(1):51-6. doi: 10.3346/jkms.2001.16.1.51.
This study was performed to elucidate the mechanism of improved oxygenation after surfactant replacement therapy in respiratory distress syndrome (RDS) of the newborn infants. In 26 newborns with RDS, end tidal-CO2 tension (PetCO2), arterial blood gas analysis and pulmonary function tests were measured at baseline, 30 min, 2 hr and 6 hr after surfactant administration. The changes in dead space/tidal volume ratio (VD/VT ratio=(PaCO2-PetCO2)/PaCO2), oxygenation index and arterial-alveolar partial pressure difference for oxygen ((A-a)DO2) were elucidated and correlated with pulmonary mechanics. Oxygenation index and (A-a)DO2 improved, and VD/VT ratio decreased progressively after surfactant administration, becoming significantly different from the baseline at 30 min and thereafter with administration of surfactant. Pulmonary mechanics did not change significantly during the observation period. VD/VT ratio showed close correlation with OI and (A-a)DO2, but not with pulmonary mechanics. These results suggest that decreased physiologic dead space resulting from the recruitment of atelectatic alveoli rather than improvement in pulmonary mechanics is primarily responsible for the improved oxygenation after surfactant therapy in the RDS of newborn.
本研究旨在阐明新生儿呼吸窘迫综合征（RDS）患儿在接受表面活性剂替代治疗后氧合改善的机制。对26例RDS新生儿，在给予表面活性剂前、给药后30分钟、2小时和6小时测量呼气末二氧化碳分压（PetCO2）、动脉血气分析和肺功能测试。阐明死腔/潮气量比值（VD/VT比值=(PaCO2 - PetCO2)/PaCO2）、氧合指数和动脉-肺泡氧分压差值（(A-a)DO2）的变化，并将其与肺力学相关联。给予表面活性剂后，氧合指数和(A-a)DO2改善，VD/VT比值逐渐降低，在给药后30分钟及之后与给予表面活性剂时相比，与基线有显著差异。在观察期内肺力学无明显变化。VD/VT比值与OI和(A-a)DO2密切相关，但与肺力学无关。这些结果表明，在新生儿RDS中，表面活性剂治疗后氧合改善主要是由于肺不张肺泡复张导致生理死腔减少，而非肺力学改善。
