不同压力制度抗荷正压呼吸的+Gz防护作用

目的探讨抗荷正压呼吸(PBG)系统中最佳的PBG压力制度. 方法 5名被试者穿GZ-2抗荷服及中囊代偿背心,在快增长率(3.0 G/s)离心机+Gz暴露时分别进行了1.6、2.4及 3.2 kPa/G 3种压力制度PBG实验.分别测定了3种压力制度PBG的抗荷性能,并对主观感觉进行评分.结果 1.6、2.4及 3.2 kPa/G 3种压力制度PBG的抗荷性能分别为2.00±0.31、2.54±0.32及2.44±0.31G;主观感觉评分表明,2.4 kPa/G压力制度PBG优于其它两者. 结论 PBG系统的压力制度以采用2.4 kPa/G为最佳.这样,既可保证PBG的抗荷性能,又可减轻PBG的副作用.

The Protection against +Gz Afforded by Pressure Breathing with Different Pressure Schedules

Objective: System of pressure breathing for +Gz (PBG) has been incorporated into service in the high performance fighter aircraft, but there were significant differences among PBG pressure schedules used in different countries. The purpose of this study was to define an optimal pressure schedule in PBG system. Method: Five male subjects wearing GZ-2 anti-G suit and medium-sized bladder vest, plus PBG with 1.6, 2.4, and 3.2 kPa/G pressure schedules, respectively, were exposed to rapid onset (3.0 G/s) centrifuge +Gz runs. +Gz protection of PBG with each of the three pressure schedules were measured and the subjective ratings were collected. Result: The +Gz protection afforded by PBG with 1.60, 2.40, and 3.20 kPa/G pressure schedules were 2.00 +/- 0.31, 2.54 +/- 0.32, and 2.44 +/- 0.31 G, respectively. Subjective ratings showed that the PBG with 2.40 kPa/G pressure schedule was better than the other two. Conclusion: Our data suggest that a PBG pressure schedule of 2.4 kPa/G in PBG system is optimal. It not only assures the anti-G performance of PBG, but also reduces its side effects.