Obstructive sleep apnea and prolonged mechanical ventilation.

Patients with prolonged mechanical ventilation have a high one year mortality, with recognized contributing factors including COPD, cardiac failure, renal failure, and respiratory muscle weakness.1 The study by Diaz-Abad et al2 shows that obstructive sleep apnea (OSA) is very common among selected obese patients who have weaned from prolonged mechanical ventilation. The study raises as many questions as it answers. Did OSA significantly contribute to the need for prolonged mechanical ventilation? Is OSA common among non-obese patients with prolonged mechanical ventilation? What is optimal evaluation for OSA among ventilator dependent and recently weaned patients? With OSA common among obese patients weaned from prolonged mechanical ventilation, could it have been diagnosed sooner? If CPAP or bi-level PAP had been started sooner, could the patients have come off mechanical ventilation sooner and been decannulated sooner?