Worsening oxygenation in the mechanically ventilated patient. Causes, mechanisms, and early detection.

Hypoxemia or worsening oxygenation is a common problem in the ICU. Ventilator-related problems, patient-related problems, including progression of the underlying disease process or superimposed disorders, and interventions, procedures, and medications can all adversely affect the patient's oxygenation status. Each of these causes should be sought for in a rapid and expeditious manner and appropriate corrective actions taken.