You have been called to a long-term nursing care facility for a 77-year-old female patient with Parkinson's disease. According to the nursing staff, she is more confused than normal and is to be transported to the emergency department for evaluation. Since the patient neither understands nor can answer any of your questions, which sign provides the best evidence that her breathing is adequate?

Airway management is the use of medical devices and procedures to maintain or restore a patient's breathing, or ventilation. Airway management techniques are aimed at reducing complications associated with artificial airways and mechanical ventilation, such as airway obstructions, infection, and retained secretions