The Management of Chronic Hypoventilation: Nasal Continuous Positive Airway Pressure (CPAP)
When the polysomnogram demonstrates frequent episodes of apnea or hypopnea during sleep in patients with chronic hypoventilation, even in those with severe obstructive or restrictive ventilatory defects, therapy should be directed at reversing the obstructive episodes. A trial of nasal CPAP should be attempted initially with pressure adjusted during the sleep study so that obstructive episodes are eliminated. Nasal CPAP has been demonstrated to be the most effective noninvasive treatment of sleep apnea syndrome and may be effective in other chronic hypoventilatory syndromes when obstructive episodes have been demonstrated. buy levaquin online
Noninvasive Mkntilatory Assistance: When chronic hypoventilation persists despite reversal of identifiable contributing factors, sleep apnea has been excluded or fails to respond to treatment with nasal CPAP alone, and a trial of pharmacotherapy fails or is deemed inappropriate, noninvasive ventilatory assistance may be tried. This refers to a variety of devices that assist ventilation without requiring placement of a permanent airway.
Many of the devices were developed during the polio epidemics of the 1930s, 1940s, and 1950s. They include “body ventilators,” consisting of negative pressure ventilators and ventilators that assist diaphragmatic motion by displacing the abdominal contents, and positive pressure ventilators that pump air through a mask secured over the nose or mouth.