Patients in whom respiratory failure is consequent on restrictive ventilatory disease experience nocturnal deterioration of their blood gas values, especially during rapid eye movement (REM) sleep. Regular nocturnal mechanical ventilation by effectively preventing these changes can improve their daytime arterial blood gas (ABG) values, exercise tolerance, and sense of well-being. For both medical and cosmetic reasons, there has been renewed interest in noninvasive mechanical ventilation, and both negative pressure and positive pressure devices have been used successfully in the management of respiratory failure. However, the mechanism by which patients improve remains unclear. A reduction in diaphragmatic and accessory muscle electromyographic (EMG) activity during ventilation has been demonstrated among healthy volunteers* and in patients with restrictive ventilatory failure. Therefore, it has been postulated that the beneficial effects of ventilatory support may be mediated, in part, by a reduction in inspiratory muscle work. antibiotic levaquin
Reported success using nocturnal positive pressure ventilation by nasal mask has only occasionally included measurements of inspiratory muscle function. Marino and Braun observed an increase in respiratory muscle strength (RMS) after five months of either negative or positive pressure ventilation for part of each day (4 to 10 h), and Ellis et al observed that after three months of nocturnal positive pressure ventilation, the improvement in daytime ABG values was associated with an improvement in inspiratory muscle strength in four of seven subjects with severe kyphoscoliosis. Accordingly, this study was undertaken to examine the long-term effects of intermittent positive pressure ventilation (IPPV) by nasal mask on inspiratory muscle endurance among patients in whom respiratory failure is secondary to restrictive ventilatory disease. Our findings suggest that following nocturnal ventilation, there is an increase in inspiratory muscle endurance.