amnion. the innermost fetal membrane, which forms a sac filled with amniotic fluid that surrounds the embryo and later the fetus; as it enlarges it gradually obliterates the chorionic cavity and enfolds the umbilical cord. Called also bag of waters.
cluster breathing. cluster breathing. a breathing pattern in which a closely grouped series of respirations is followed by apnea. The activity is associated with a lesion in the lower pontine region of the brainstem. See also Biot's respiration, Cheyne-Stokes respiration.
By Jose Luis Mendez, MD and Eric J. Olson, MD Abstract: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common, yet often overlooked, form of symptomatic sleep-disordered breathing. OSAHS is a cause for concern for several reasons, one of which is its association with cardiovascular disease.