Rodeberg D A, Easter A J, Washam M A, Housinger T A, Greenhalgh D G, Warden G D
Shriners Burns Institute, University of Cincinnati College of Medicine, OH 45229-3095, USA.
J Burn Care Rehabil. 1995 Sep-Oct;16(5):476-80. doi: 10.1097/00004630-199509000-00003.
A mixture of helium and oxygen is less dense than room air. This property allows the gas to flow with less turbulence past airway narrowings, thereby decreasing airway resistance and increasing the volume of gas exchange. Previous studies demonstrated that airway obstruction that is manifested by stridor was present in 92% of patients requiring reintubation. Eight pediatric patients with burns in whom postextubation stridor or retractions unresponsive to racemic epinephrine developed, were treated with "heliox" (helium and oxygen) for 28 +/- 5 hours with an initial helium concentration between 50% and 70%. Of the eight patients treated with heliox, only two experienced respiratory distress and required reintubation. Both patients had stridor for a longer time before the initiation of heliox therapy compared with those patients who did not require reintubation. After initiation of heliox therapy, patients experienced a significant decrease in respiratory distress scores (6.8 +/- 0.7 vs 2.0 +/- 0.7). Heliox was able to relieve persistent stridor and thereby aid in the prevention of respiratory distress and reintubation.
氦气和氧气的混合气体密度低于室内空气。这一特性使该气体在流经气道狭窄处时湍流较小,从而降低气道阻力并增加气体交换量。先前的研究表明,在需要重新插管的患者中,92%存在以喘鸣为表现的气道梗阻。8名烧伤的儿科患者在拔管后出现对消旋肾上腺素无反应的喘鸣或呼吸回缩,接受了“氦氧混合气”(氦气和氧气)治疗28±5小时,初始氦气浓度在50%至70%之间。在接受氦氧混合气治疗的8名患者中,只有2名出现呼吸窘迫并需要重新插管。与那些不需要重新插管的患者相比,这两名患者在开始氦氧混合气治疗前喘鸣的时间更长。开始氦氧混合气治疗后,患者的呼吸窘迫评分显著降低(6.8±0.7对2.0±0.7)。氦氧混合气能够缓解持续性喘鸣,从而有助于预防呼吸窘迫和重新插管。