[Investigation of the application of electrical impedance principle for the diagnosis of diaphragm fatigue].
We designed and performed the chest and abdomen impedance respirograph (IRG), which included the one dimentional IRG and the two dimentional IRG, by applying the principle of bioelectrical impedance. Using IRG, we measured the non-synchronized chest and abdomen respiratory motions occurring in the diaphragmatic fatigue. The results showed that all 203 normal control subjects showed synchronized pattern of chest and abdomen respiratory motions. In 189 COPD patients 117 (61.9%) showed non-synchronized respiratory motions which could be further divided into three types: type I showed complete contradirectional movements of respiration, M > 24% and alpha angle > 120 degrees; type II showed staggered peak of the chest and abdomen motion curves, 13% < M < 24%, 50 degrees < alpha angle < 120 degrees; type III showed double peaks in the one dimentional IRG and 8-shaped double circles in the two dimentional IRG, M < 13%, alpha angle > 40 degrees. When compared with Pdi and diaphragm myoelectricity frequency spectrum the rates of accordance were 81.8% and 90%, respectivity, suggesting that IRG could be reliably used to diagnose diaphragmatic fatigue. This technique is simple, easy, cheap and non-invasive. It is, therefore, worth to be widely recommanded for clinical investigation.
Niu
R
R
Research Department, Tongji Hospital Affiliated in Tongji Medical University, Wuhan.
Zhao
J
J
D000368:Aged; D000818:Animals; D003964:Diaphragm / Q000503:physiopathology; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D018763:Muscle Fatigue / Q000502:physiology*; D011817:Rabbits