EFFECTS OF (NCPAP) ON CARDIAC-FUNCTION AWAKE AND ASLEEP

Continuous positive airway pressure (CPAP) leads to a fall in cardiac output (CO) when applied to individuals with normal cardiac function. However, some reports indicate that CPAP improves CO in selected patie nts with congestive heart failure, although other reports disagree. Na sal CPAP effectively reverses obstructive sleep apnoea, a condition in which vigorous inspiratory efforts against an occluded upper airway c an induce falls in CO, The cardiovascular effects of CPAP in such pati ents will depend on the balance between the indirect cardiac benefits resulting from relief of apnoeas, and the direct effects of positive p ressure on the heart itself.