Genioglossus fatigue in obstructive sleep apnea

Effects of tongue position and lung volume on voluntary maximal tongue protrusion force in humans

“…Resting length is usually used with the tongue tip near the incisors to measure maximal force of voluntary tongue protrusion (Blumen et al, 2002(Blumen et al, , 2004Eastwood et al, 2003;Eckert et al, 2011;McSharry et al, 2012;Mortimore et al, 1999Mortimore et al, , 2000Pittman and Bailey, 2008;Scardella et al, 1993) or retraction (Ulrich Sommer et al, 2014). As the human tongue is a unique structure with four pairs of intrinsic and extrinsic muscles acting as a hydrostat (incompressible with a constant volume), its capacity to generate protrusion force is likely to reflect the action of several muscles (Abd-El-Malek, 1938;Anderson, 1881;Takemoto, 2001).…”

Is continuous positive airway pressure necessarily an everyday therapy in patients with obstructive sleep apnoea?

“…It is also possible that this reduction in oedema might improve reflex pharyngeal dilator muscle activity in response to improved mucosal surface receptor activity [16,17]. Others have suggested that increased pharyngeal dilator muscle activity might lead to a degree of chronic muscle fatigue [18] that could be reversible following a period on CPAP. These causes of a temporary cure might then hold for a variable period of time until OSA begins to return perhaps, for example, following a period of increased alcohol intake, an upper respiratory tract infection or enforced supine sleeping (following an operation, for example); it would then require further CPAP therapy to reverse the damage done.…”

Sex, stress and sleep apnoea: Decreased susceptibility to upper airway muscle dysfunction following intermittent hypoxia in females

“…Tongue strength is predictive of airway patency in OSAS (Kanezaki et al, 2015), and lower tongue stiffness (Brown et al, 2015) and increased fatigue (McSharry et al, 2012) are observed in OSAS patients, but little is known concerning potential sex differences in OSAS notwithstanding that tongue protrusion force and fatigue are equivalent in healthy males and females (Mortimore et al, 1999), with weakness evident in ageing in both sexes (Mortimore et al, 1999). Upper airway muscle contractile and endurance properties have been comprehensively examined in rodent models and are equivalent in naïve males and females (Cantillon & Bradford, 1998Skelly et al, 2012a;Lewis et al, 2016).…”