Respiratory muscle activity during rapid eye movement (REM) sleep in patients with chronic obstructive pulmonary disease.

Abstract

Background -In patients with chronic obstructive pulmonary disease (COPD) periods of hypopnoea occur during rapid eye movement (REM) sleep, but the mechanisms involved are not clear. Methods -Ten patients with stable COPD were studied during nocturnal sleep. Detailed measurements were made ofsurface electromyographic (EMG) activity of several respiratory muscle groups and the accompanying chest wall motion using magnetometers. Results -Hypopnoea occurred in association with eye movements during phasic rapid eye movement (pREM) sleep. During pREM sleep there were reductions in EMG activity of the intercostal, diaphragm, and upper airway muscles compared with non-REM sleep. Episodic hypopnoea due to partial upper airway occlusion ("obstructive" hypopnoea) was seen consistently in four subjects while the others showed the pattern of "central" hypopnoea accompanied by an overall reduction in inspiratory muscle activity. Although activity of the intercostal muscles was reduced relatively more than that of the diaphragm, lateral rib cage paradox (Hoover's sign) was less obvious during pREM-related hypopnoea than during wakefulness or non-REM sleep. Conclusions -Hypopnoea during REM sleep in patients with COPD is associated with reduced inspiratory muscle activity.The pattern of hypopnoea may be either "obstructive" or "central" and is generally consistent within an individual. Relatively unopposed action of the diaphragm on the rib cage during REM sleep is not accompanied by greater lateral inspiratory paradox. (Thorax 1995;50:376-382) Keywords: REM sleep, chronic obstructive pulmonary disease, respiratory muscle activity, hypopnoea.Ventilation during rapid eye movement (REM) sleep is characterised by its variability both within and between subjects."2 In patients with chronic obstructive pulmonary disease (COPD) periods of hypopnoea in REM sleep result in hypoxaemia, but the precise mechanisms are uncertain. In healthy subjects reduced respiratory muscle activity has been shown in REM sleep3-5; this is generally most marked in those respiratory muscles which also have a postural function, with activity of the diaphragm being relatively spared or even increasing. Patients with airways obstruction due to COPD,"8 have been reported to show a similar pattern during REM sleep, but the results have been variable and the numbers of patients studied in detail are few.One potential consequence of discoordinate inspiratory muscle action is recurrent upper airway narrowing or occlusion. Although early work on nocturnal hypoxaemia in patients with COPD suggested that obstructive apnoea was frequently present,9 the population studied was highly selected and later work appeared to refute this conclusion.'0 It has subsequently been shown, however, that the clinical features associated with the obstructive sleep apnoea syndrome can be seen with obstructive hypopnoea rather than complete apnoea. " In patients with COPD it is not clear to what extent diminished activity of the upper airway muscles in REM sleep may result in...

Pulmonary hyperinflation a clinical overview

“…WHITE et al [52] further investigated whether distortions of chest wall movement, in particular worsening lateral paradox, might contribute to hypoxaemia during REM sleep. They hypothesized that reduction in activity of inspiratory muscles other than the diaphragm in REM sleep might lead to greater distortion, but in the event Hoover's sign during REM sleep became less evident, rather than more evident, presumably as a consequence of the reduced force of diaphragmatic contraction ( fig.…”

Screening for sleep-disordered breathing in neuromuscular disease using a questionnaire for symptoms associated with diaphragm paralysis

“…Whilst the majority of patients have obstructive sleep apnoea (OSA) [4,5], other causes of SDB may similarly cause health problems [6][7][8][9][10][11][12]. In the present study, we considered the group of patients with neuromuscular disease (NMD) who are affected by SDB because of weakness of the respiratory muscles [9,[13][14][15][16][17][18] influenced by posture and sleep stage [9,19] and who do not necessarily present with symptoms, such as daytime fatigue, that are measured by the Epworth Sleepiness scale (ESS) [20].…”

Desafios Na Captação Do Sinal De Eletromiográfico Do Músculo Diafragma

“…Na literatura há artigos que contemplam o posicionamento dos eletrodos no diafragma em EMGs, e cada um desses artigos trazem posicionamentos diferentes. Porém locais próximos [8,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34].…”