Evidence-based ventilator weaning and discontinuation.

Ventilator management of a patient who is recovering from acute respiratory failure must balance competing objectives. Discontinuing mechanical ventilation and removing the artificial airway as soon as possible reduces the risk of ventilator-induced lung injury, nosocomial pneumonia, airway trauma from the endotracheal tube, and unnecessary sedation, but premature ventilator-discontinuation or extubation can cause ventilatory muscle fatigue, gas exchange failure, and loss of airway protection. In 1999 the McMaster University Outcomes Research Unit conducted a comprehensive evidence-based review of the literature on ventilator-discontinuation. Using that literature review, the American College of Chest Physicians, the Society of Critical Care Medicine, and the American Association for Respiratory Care created evidence-based guidelines, which include the following principles: 1. Frequent assessment is required to determine whether ventilatory support and the artificial airway are still needed. 2. Patients who continue to require support should be continually re-evaluated to assure that all factors contributing to ventilator dependence are addressed. 3. With patients who continue to require support, the support strategy should maximize patient comfort and provide muscle unloading. 4. Patients who require prolonged ventilatory support beyond the intensive care unit should go to specialized facilities that can provide more gradual support reduction strategies. 5. Ventilator-discontinuation and weaning protocols can be effectively carried out by nonphysician clinicians.