Mador M Jeffery, Khan Saadat, Kufel Thomas J
Division of Pulmonary, Critical Care and Sleep Medicine, State University of New York at Buffalo, Buffalo, NY 14215, USA.
Chest. 2002 Feb;121(2):452-8. doi: 10.1378/chest.121.2.452.
Measurement of twitch transdiaphragmatic pressure (TwPdi) during bilateral phrenic nerve stimulation is presently the best method to detect diaphragmatic fatigue in humans. The stimulation methods that are currently employed (ie, transcutaneous electrical stimulation [TES] and cervical magnetic stimulation [CMS]) have limitations. Bilateral anterolateral magnetic stimulation of the phrenic nerves (BAMPS) was recently described. The purpose of this study was to determine whether BAMPS can reliably detect diaphragmatic fatigue, and to compare the results with BAMPS with those obtained with the other stimulation techniques.
Twelve healthy subjects participated in the study.
TwPdi was measured during TES, CMS, and BAMPS before and 10, 30, and 60 min after a potentially fatiguing task. Voluntary hyperpnea to task failure was used as the fatiguing task because this task has previously been shown to reliably produce contractile fatigue of the diaphragm. To determine the reproducibility of BAMPS, TwPdi was measured before and after a nonfatiguing task in 10 of the subjects.
TwPdi fell significantly after the hyperpneic task with all three stimulation techniques, and the amount by which TwPdi fell after hyperpnea was not significantly different for the different stimulation techniques. The percentage fall in TwPdi after hyperpnea was significantly correlated between stimulation techniques (CMS vs BAMPS, r = 0.72; TES vs BAMPS, r = 0.84; and TES vs CMS, r = 0.67). The mean (+/- SE) within-subject, between-trial coefficient of variation for TwPdi during BAMPS was 5.1 +/- 0.1%.
BAMPS is highly reproducible and at least as good at detecting diaphragmatic fatigue as the other stimulation techniques.
双侧膈神经刺激期间测量抽搐跨膈压（TwPdi）是目前检测人类膈肌疲劳的最佳方法。目前所采用的刺激方法（即经皮电刺激 [TES] 和颈部磁刺激 [CMS]）存在局限性。最近有人描述了双侧膈神经前外侧磁刺激（BAMPS）。本研究的目的是确定BAMPS能否可靠地检测膈肌疲劳，并将BAMPS的结果与其他刺激技术所获得的结果进行比较。
12名健康受试者参与了本研究。
在进行一项可能导致疲劳的任务之前以及之后10、30和60分钟，分别通过TES、CMS和BAMPS测量TwPdi。将自愿性过度通气直至任务失败用作疲劳任务，因为此前已证明该任务能可靠地导致膈肌收缩性疲劳。为了确定BAMPS的可重复性，对10名受试者在非疲劳任务前后测量TwPdi。
采用所有三种刺激技术时，过度通气任务后TwPdi均显著下降，且不同刺激技术过度通气后TwPdi下降的幅度无显著差异。不同刺激技术之间，过度通气后TwPdi下降的百分比显著相关（CMS与BAMPS，r = 0.72；TES与BAMPS，r = 0.84；TES与CMS，r = 0.67）。BAMPS期间TwPdi的受试者内、试验间平均变异系数为5.1±0.1%。
BAMPS具有高度可重复性，在检测膈肌疲劳方面至少与其他刺激技术一样有效。
