Prolonged mechanical ventilation
The decision to intubate and begin mechanical ventilation in patients with acute respiratory failure is based on the observation of signs and symptoms of hypoxemia or hypercarbia or both. The decision is less thought-provoking when the patient has stopped breathing under circumstances such as cardiac arrest, drug overdose, or fatigue and retention of secretions. In less acute circumstances, the question of when and how to wean a patient from mechanical ventilation should be raised even before the patient is intubated. The two main reasons for this: (1) there are terminal diseases that can be prolonged unmercifully by instituting mechanical ventilation, and (2) knowledge of the predisposing causes of respiratory failure will determine the therapeutic approach.
The purpose of this review is threefold. The first is to describe 15 patients with respiratory failure hospitalized in the Medical Intensive Care Unit of the Cleveland Clinic. The second is to present a logical approach to weaning from mechanical ventilation, and the third is to emphasize the necessity of using a physiological approach to the problem of weaning rather than through trial and error.Patients
All patients initially had presenting symptoms of respiratory failure and had received mechanical ventilation for at least 2 weeks before weaning or were specifically referred to the Cleveland Clinic to be weaned. Of 15 patients, eight were referred from within a 300-mile radius. Three could not be completely weaned (patients 1, 4, and 7). Eleven patients are still living; two patients died of respiratory failure 6 months and one . . .