Acute or chronic respiratory failure. Assessment and management of patients with COPD in the emergency setting.

Patients with acute or chronic respiratory failure exhibit severe pulmonary impairment as a baseline characteristic. Additional minor insults can precipitate cardiopulmonary failure that requires hospital admission and possibly mechanical ventilation. Our approach to these patients emphasizes evaluation of the imbalance between neuromuscular competence and mechanical load on the respiratory system. In this way, reversible factors can be identified and corrected before they progress to inspiratory muscle fatigue and respiratory failure. For cases in which deterioration is inexorable, guidelines for mechanical ventilation are given and approaches to eventual liberation from the ventilator are reviewed.