Pathogenesis of apneas in hypersomnia-sleep apnea syndrome

The American review of respiratory disease (Impact Factor: 10.19). 03/1982; 125(2):167-74.
Source: PubMed


To define the pathogenesis of apneas, eight patients with hypersomnia-sleep apnea syndrome were studied during nocturnal sleep. Diaphragmatic and genioglossal electromyograms quantitated as moving time average activity showed parallel periodic fluctuations resembling the pattern of Cheyne-Stokes breathing. Hypopneas and occlusive apneas occurred at the nadir of these cyclic changes, and mixed apneas represented an extreme of this periodicity with no inspiratory activity at the nadir of the cycle. Tracings of central apneas were compatible with an extremely prolonged expiratory phase. Electromyogram activity of both muscles showed an inversely linear relationship with oxygen saturation but genioglossal activity at the resolution of upper airway occlusion was increased out of proportion to the increase in diaphragmatic activity and the degree of oxygen desaturation. These results indicated that occlusive and mixed apneas result from an instability of ventilatory control during sleep, which seems to be an exaggeration of periodic breathing observed at sleep onset.

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    • "As outlined above, considerable research and clinical interest has centered on the GG and more specifically, on the " phasic inspiratory " activities of this muscle (Berry et al., 1997; Hudgel and Harasick, 1990; Hudgel et al., 1984; Onal et al., 1982; Pillar et al., 2001). By the same token, studies conducted by White and colleagues drew attention to the " tonic " component and the potential for this " background " activity that persists through inspiration and expiration to contribute to airway patency in the presence of an anatomically compromised airway (Fogel et al., 2001; Fogel et al., 2005; McGinley et al., 2008; Mezzanotte et al., 1992; Tangel et al., 1992; Tangel et al., 1991; Wiegand et al., 1991). "
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