Should we routinely screen for hypercapnia in sleep apnea patients before elective noncardiac surgery?

Yes. Obesity hypoventilation syndrome (OHS) is often undiagnosed and greatly increases perioperative risk.Therefore, we recommend trying to detect OHS in a timely manner.Treatment should begin without delay to avoid adverse perioperative outcomes, which can include acute-on-chronic respiratory failure requiring intensive-care monitoring and invasive mechanical ventilation, or death.