Patients with Chronic Paralytic/Restrictive Ventilatory Dysfunction (6)
George et al demonstrated that the number of episodes of dSa02 of greater than 3 percent that last for at least 10 s and that have a particular slope predicts the total number of poly-somnographically derived apneas and hypopneas with 98 percent sensitivity and very few false positives and false negatives. We manually counted the number of episodes of ^4 percent dSa02 (4%dSa02) occurring with rapid recovery. Since patients are mechanically ventilated, apneas and hypopneas cannot be central in origin and, therefore, must either be obstructive or reflect hypoventilation from ineffective BV assistance. In the latter case, the slope from the baseline and the recovery from the nadir to the baseline would not be expected to be abrupt.
Our goal was to determine the incidence and severity of dSa02 and thus to estimate the incidence of obstructive apneas and hypopneas occurring in patients using BVs. These factors were correlated with symptoms. The incidence of systemic hypertension was also determined for this population. buy flovent inhaler
Patients and Methods
Thirty-seven BV users with paralytic/restrictive ventilatory insufficiency were studied. Fifteen patients complained of symptoms of ventilatory insufficiency despite nocturnal BV use.