Change of diaphragm electromyograms in patients with obstructive sleep apnea-hypoventilation syndrome and its significance / 中华全科医师杂志

ABSTRACT

Objective To explore change of diaphragm electromyograms in patients with obstructive sleep apnea-hypoventilation syndrome (OSAHS) before and after nocturnal sleep, as well as effective nasal continuous positive airway pressure (n-CPAP) ventilation treatment for more than two months. Methods Diaphragm electromyogram was recorded with chest surface electrodes in 22 patients with moderate and severe OSAHS and 24 normal people, and phrenic nerve conduction time (PNCT) and diaphragm compound muscle action potential (CMAP) provoked by unilateral magnetic stimulation (UMS) were measured for them before and after sleep. Measurements were repeated for five patients with severe OSAHS after effective OSAHS patients before and after nocturnal sleep than that in normal people bilaterally, (8.4±0. 6)ms and (8.4±0. 9)ms vs (7. 3±0. 8)ms and (7. 3±0. 8) ms for the left side; and (8.4±1.3) ms and (8. 9 ± 0. 8) ms vs (7.2 ± 0. 8) ms and (7.2 ± 0. 8 ) ms for the right side ( P < 0. 01 ), respectively ; and amplitude of CMAP was significantly lower in OSAHS patients, (0. 60±0. 20)mV and (0. 64±0. 29)mV vs (0. 98 ± 0. 28)mV and (0. 97±0. 27)mV for the left side; and (0. 53±0. 23)mV and (0. 56±0. 26)mV vs (0. 93 ±0. 29) mV and ( 0. 94 ± 0. 29 ) mV for the right side, respectively ( P < 0. 01 ) ; but no significant significantly shortened bilaterally in five patients with severe OSAHS after effective n-CPAP ventilation treatment for more than two months, (8.6±0. 7)ms vs (7.4±0. 5)ms for the lfet side and (7. 8±0. 6)ms vs (6.4 ± 0. 6) ms for the fight side ( P < 0. 05 ), respectively. Conclusions Both phrenic nerve conduction and diaphragm muscle function are weakened in patients with OSAHA, which may be related to hypoxia and/ or disturbance of sleep structure at night.