Safety Pressure Effects in a Mechanical Demand Regulator.

IF 0.9 4区医学 Q4 BIOPHYSICS

Aerospace medicine and human performance Pub Date : 2025-07-01 DOI:10.3357/AMHP.6420.2025

Barbara E Shykoff, DeAnne C French, Dan E Warkander, F Eric Robinson

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Abstract

Introduction: Most U.S. Navy, but few U.S. Air Force, tactical jets use safety pressure (SP) regulators. SP effects have been studied only with confounding differences in regulator design. We compared a CRU-103 SP regulator to a CRU-103 with SP removed. The hypothesis was that SP does not alter breathing, only shifts pressure more positive.

Methods: Inspiratory flows and mask and hose pressures were measured in 24 subjects (29 for speech at rest, 31 for lung volumes) who breathed in counterbalanced order from both regulators while blind to SP condition.

Results: Both were easy to breathe. Neither was preferred overall. Between regulators, end-expiratory lung volume did not differ. SP stabilized hose pressure and favored inspiration: without speech, hose pressure swings were significantly lower (rest: 25%, exercise: 33%), as were inspiratory work of breathing at rest (33%) and peak inspiratory flow magnitude (rest: 14%; exercise: 11%). Waveforms showed interactions of mask valves and SP at the start and end of expiration. Mask leaks with SP activated the regulator during speech.

Discussion: SP as implemented in the CRU-103 causes mostly subtle differences in pressures and flows. The sensed difference during expiration may result from the initial large pressure gradient for expiratory flow. Shykoff BE, French DC, Warkander DE, Robinson FE. Safety pressure effects in a mechanical demand regulator. Aerosp Med Hum Perform. 2025; 96(7):547-555.

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机械需求调节器中的安全压力效应。

简介：大多数美国海军，但少数美国空军，战术喷气机使用安全压力（SP）调节器。SP效应只在调节器设计的混杂差异下进行过研究。我们将CRU-103 SP调节器与去除SP的CRU-103进行了比较。假设是SP不会改变呼吸，只会使压力更积极。方法：对24名受试者（29名静止言语组，31名肺容量组）进行了吸气流量、面罩和软管压力的测量，这些受试者在无SP条件下以两种调节器的平衡顺序呼吸。结果：两组患者均呼吸顺畅。总体而言，这两项都不是首选。在不同的调节剂之间，呼气末肺容量没有差异。SP稳定了软管压力并有利于吸气：在没有说话的情况下，软管压力波动明显降低（休息：25%，运动：33%），休息时呼吸的吸气功（33%）和吸气流量峰值(休息：14%；练习:11%)。波形显示掩膜阀和SP在过期开始和结束时的相互作用。面具泄漏与SP激活调节器在讲话期间。讨论：在cr -103中实施的SP会导致压力和流量的细微差异。在呼气过程中所感知到的差异可能是由于呼气气流的初始压力梯度大所致。Shykoff BE, French DC, Warkander DE, Robinson FE。机械需求调节器中的安全压力效应。航空航天Med Hum Perform. 2025；96(7): 547 - 555。

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来源期刊

Aerospace medicine and human performance PUBLIC, ENVIRONMENTAL & OCCUPATIONAL HEALTH -MEDICINE, GENERAL & INTERNAL

CiteScore

1.10

自引率

22.20%

发文量

272

期刊介绍： The peer-reviewed monthly journal, Aerospace Medicine and Human Performance (AMHP), formerly Aviation, Space, and Environmental Medicine, provides contact with physicians, life scientists, bioengineers, and medical specialists working in both basic medical research and in its clinical applications. It is the most used and cited journal in its field. It is distributed to more than 80 nations.