Am J Vet Res. 2024 Jun 5;85(8). doi: 10.2460/ajvr.24.02.0036. Print 2024 Aug 1.
To investigate the effects of FLow-controlled EXpiration (FLEX) ventilation expiration time and speed on respiratory and pulmonary mechanics in anesthetized horses in dorsal recumbency.
6 healthy adult research horses.
In this randomized crossover experimental study, horses were anesthetized 3 times and were ventilated each time for 60 minutes using conventional volume-controlled ventilation (VCV), linear emptying of the lung over 50% of the expiratory time (FLEX50), or linear emptying of the lung over 100% of the expiratory time (FLEX100) in a randomized order. The primary outcome variables were dynamic compliance (Cdyn), hysteresis, and alveolar dead space. The data was analyzed using two-factor ANOVA. Significance was set to P < .05.
Horses ventilated using FLEX50 and FLEX100 showed significantly higher Cdyn and significantly lower hysteresis values compared to horses ventilated using VCV. Horses ventilated using FLEX50 had significantly lower alveolar dead space compared to horses ventilated using FLEX100 or VCV. Horses ventilated using FLEX100 had significantly lower alveolar dead space compared to VCV horses.
Our results demonstrate improved Cdyn, hysteresis, and alveolar dead space in horses ventilated with either FLEX50 or FLEX100 relative to traditional VCV. The use of FLEX with a faster exhalation speed (FLEX50) offers additional respiratory advantages.
研究在仰卧位麻醉马中，流量控制呼气（FLEX）呼气时间和速度对呼吸和肺力学的影响。
6 匹健康成年研究马。
在这项随机交叉实验研究中，马被麻醉 3 次，每次使用常规容量控制通气（VCV）、50%呼气时间线性排空（FLEX50）或 100%呼气时间线性排空（FLEX100）通气 60 分钟，以随机顺序进行。主要观察变量为动态顺应性（Cdyn）、滞后和肺泡死腔。数据采用双因素方差分析进行分析。设 P<0.05 为差异有统计学意义。
与 VCV 通气的马相比，使用 FLEX50 和 FLEX100 通气的马的 Cdyn 显著升高，滞后显著降低。与 FLEX100 或 VCV 通气的马相比，使用 FLEX50 通气的马的肺泡死腔显著降低。与 VCV 通气的马相比，使用 FLEX100 通气的马的肺泡死腔显著降低。
我们的结果表明，与传统的 VCV 相比，使用 FLEX50 或 FLEX100 通气的马的 Cdyn、滞后和肺泡死腔得到改善。更快呼气速度（FLEX50）的 FLEX 使用提供了额外的呼吸优势。
