Effect of Short Term Graded Withdrawal of Nasal Continuous Positive Airway Pressure on Systemic Blood Pressure in Patients with Obstructive Sleep Apnoea

Stradling JR, Partlett J, Davies RJO, Siegwart D, Tarassenko L.Effect of short term graded withdrawal of nasal continuous positive airway pressure on systemic blood pressure in patients with obstructive sleep apnoea.It is debated whether obstructive sleep apnoea (OSA) is a significant independent risk factor for sustained hypertension or cardiovascular morbidity and mortality. In an attempt to avoid the problem of confounding variables we have investigated whether withdrawing nasal continuous positive airway pressure (NCPAP) from patients with OSA for different proportions of the night leads to a subsequent rise in their morning blood pressures. Six patients with treated OSA had their NCPAP automatically varied between 3 cms H20 and a therapeutic pressure over 5 successive nights. The proportion of therapeutic NCPAP given was kept constant over the 5 nights and blood pressure measured the morning after the 5th night. Each patient had 5 different levels of sleep disruption, from no therapeutic NCPAP at all...