Tracheostomy and hemodynamic changes in sleep-inducing apnea.

Because pulmonary hypertension and systemic hypertension occur during sleep-induced obstructive apnea, six patients underwent overnight hemodynamic monitoring before and after tracheostomy. Variables studied included heart rate, pulmonary artery pressure, femoral artery pressure, and arterial oxygen tension (Po2). After tracheostomy, significant reductions were noted during sleep in mean pulmonary artery pressure from 45 +/- 6 mm Hg (mean +/- SEM) to 22 +/- 2 mm Hg (P less than 0.05) and in mean femoral artery pressure from 137 +/- 6 mm Hg to 97 +/- 3 mm Hg (P less than 0.005). There was also a significant increase for the group in arterial Po2 recorded during the apneic episodes from 38 +/- 3 mm Hg before tracheostomy to 71 +/- 2 mm Hg (P less than 0.001) after tracheostomy. We conclude that tracheostomy improves the hemodynamic abnormalities and hypoxemia that occur during sleep in patients with sleep-induced obstructive apnea.