Hypoxia reduces the conduction velocity of the excitation along the striated muscles in man.
The conduction velocity of the excitation along the striated muscles in man, hereafter refered to as muscle fiber conduction velocity (MFCV) was used to estimate the muscle functional state under hypoxaemic hypoxia. The averaged MFCV was counted by the method based on the surface measurements (using bipolar "branched" multielectrodes) of the electrically elicited compound action potentials of the brachial biceps muscle. The arterial and venous blood-gas and acid-base parameters were simultaneously measured and the body temperature was controlled intramuscularly. With afebrile patients under normoxaemia or hypoxaemia following brain stroke, MFCV decreased proportionnally to the arterial partial oxygen pressure (PaO2) rate; a strong positive correlation (r = 0.882) between MFCV and PaO2 was found up to PaO2 of 12.0 kPa and MFCV 3.5 m/s. In the case of over PaO2 = 12.0 kPa, the relationship entered into saturation; the further increase PaO2 was not followed by concomitant changes in MFCV. The results show that MFCV-testing is a valuable tool to evaluate the functional state of the striated muscle under hypoxia.
Gerilovsky
L
L
Central Laboratory of Biophysics, Bulgarian Academy of Sciences, Sofia.
Karadimov
D
D
Ianakiev
B
B
D000200:Action Potentials / Q000502:physiology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002245:Carbon Dioxide / Q000097:blood; D004576:Electromyography / Q000379:methods; D004594:Electrophysiology; D005260:Female; D006454:Hemoglobins; D006801:Humans; D006863:Hydrogen-Ion Concentration; D000860:Hypoxia / Q000097:blood / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000503:physiopathology*; D010100:Oxygen / Q000097:blood
D006454:Hemoglobins; D002245:Carbon Dioxide; D010100:Oxygen