Diaphragm electromyogram root mean square response to hypercapnia and its intersubject and day-to-day variation

Author:

Singh Bhajan,Panizza Janine A.,Finucane Kevin E.

Abstract

Diaphragm activation can be quantified by measuring the root mean square of crural EMG (RMSdi) (Beck J, Sinderby C, Lindstrom L, and Grassino A, J Appl Physiol 85: 1123–1134, 1998). To examine intersubject and day-to-day variation in the RMSdi-Pco2 relationship, end-tidal Pco2, minute ventilation (V̇e), respiratory frequency (fB), and RMSdi were measured in seven healthy subjects on two occasions during steady-state ventilation at seven levels of inspired O2 fraction (FiCO2) from 0 to 0.08 in random order. RMSdi was measured with a multielectrode esophageal catheter and controlled for signal contamination and diaphragm position. RMSdi was normalized for values obtained during quiet breathing at functional residual capacity, at FiCO2 of 0.04, and during an inspiratory capacity maneuver (RMSdi%max) as well as ECG R-wave amplitude at functional residual capacity (RMSdi/ECGR), fB, and thickness of the costal diaphragm measured by ultrasound. RMSdi increased linearly with Pco2 (mean r2 = 0.83 ± 0.10); at the highest FiCO2, RMSdi%max was 40.2 ± 11.6%. Relative to the intersubject variation in the V̇e-Pco2 relationship, intersubject variations in the slopes and intercepts of the RMSdi-Pco2 relationships were 1.7 and 1.8 times, respectively, and RMSdi%max-Pco2 relationships 0.9 and 1.3 times, respectively, and were unrelated to fB and diaphragm thickness. Relative to the day-to-day variation in the V̇e-Pco2 relationship, day-to-day variation in the slopes and intercepts of the RMSdi-Pco2 relationships were 2.8 and 4.4 times, respectively, and RMSdi/ECGR-Pco2 relationships 1.3 and 2.2 times, respectively. It was concluded that the RMSdi-Pco2 relationship measures chemosensitivity and is best compared between subjects via RMSdi%max and on separate occasions in the same subject via RMSdi/ECGR.

Publisher

American Physiological Society

Subject

Physiology (medical),Physiology

Cited by 15 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3