Body position during sleep influences the frequency of apneas and hypopneas in 50 to 60% of individuals with obstructive sleep apnea (OSA). In such cases, the apnea-hypopnea index (AHI) is increased in the supine posture and lower in the lateral posture. Positional sleep apnea is said to be present when…
In summary, studies of supplemental oxygen administered for short periods of time (one night) have demonstrated improvement in minimal or nadir Sa02, and some worsening of respiratory acidosis. Generally, there is slight prolongation of mean apnea duration, but overall time spent in apnea during sleep may actually be less in…
It could be that fixed pulmonary vascular changes on the basis of COPD had occurred, which supplemental oxygen could not have corrected. Recent studies indicate that about 20 percent of sleep apnea patients will have pulmonary hypertension at the time of diagnosis. Most of these will have daytime hypoxemia on…
The group 2 subjects with OSA and COPD who used home oxygen alone or with other therapies (protriptyline, N = 2; uvulopalatopharyngoplasty, N = 4) showed no improvement in pulmonary artery pressure or vascular resistance at 12 to 24 months* follow-up and no improvement in right ventricular ejection fraction (Fig…
A major goal in demonstrating an objective response to chronic nasal oxygen therapy would be to show hemodynamic improvement in sleep apnea patients with cardiovascular abnormalities resulting from recurrent nocturnal hypoxemia. Due to the inherent difficulty of long-term cardiovascular studies, including the invasiveness and time required for long-term follow-up, there…
Four subjects had improvement in symptoms during the oxygen month, and four had improvement during the placebo month. The two patients who showed the greatest reduction in apnea frequency with acute oxygen administration showed the greatest symptomatic improvement on placebo. There was, however, no change in mean sleep latency time…
To the clinician treating patients with OSA, the long-term clinical outcome of patients treated with nasal supplemental oxygen should be of primary importance. For example, are symptoms improved and are hemodynamic sequelae of apnea reversed?