Nocturnal noninvasive positive pressure ventilation (NIV) reduces hypercapnia, improves symptoms, and increases exercise capacity in patients with cystic fibrosis (CF), according to a report in the January issue of Thorax.
NIV has been shown to benefit patients with hypercapnia due to kyphoscoliosis, neuromuscular disease, and chronic obstructive pulmonary disease, the authors explain, and earlier studies demonstrated improved gas exchange and reduced work of breathing during single overnight sessions of NIV in CF patients.
Dr. Alan C. Young from The Alfred Hospital and Monash University, Melbourne, Victoria, Australia and colleagues assessed the benefits of nocturnal NIV versus nocturnal air or nocturnal oxygen in a crossover study of eight patients with stable CF with impaired nocturnal gas exchange and daytime hypercapnia.
None of the three treatments significantly affected sleep architecture, awake arterial blood gas measurements, or lung function, the authors report.
NIV, however, produced significant reductions in maximum pressure of transcutaneous CO2 (PtcCO2) and attenuated the rise of PtcCO2 from non-REM to REM sleep.
All but one of the seven patients who tolerated NIV increased their shuttle distance by at least 50 meters compared with air treatment, the report indicates.
NIV significantly improved chest symptom scores and transition dyspnea indices, the investigators say, while air or supplemental oxygen brought no significant changes.
None of the interventions was associated with significant changes in neurocognitive function.
"We have shown that 6 weeks of nocturnal NIV can significantly improve nocturnal hypoventilation, chest symptoms, exertional dyspnea, and peak exercise capacity in CF subjects with daytime hypercapnia," the authors conclude.
"However," the researchers add, "there is a need for larger multicenter trials to further extend these findings, clarify which subgroups may benefit most, and, in particular, determine whether NIV can improve survival."
