Weaning older patients from long-term mechanical ventilation: a pilot study.

BACKGROUND As older persons in the intensive care unit increasingly require long-term mechanical ventilation, accurate indications of readiness for weaning from ventilatory support are needed to avoid premature extubation. OBJECTIVE To describe temporal changes in pulmonary and systemic variables in older adults receiving long-term mechanical ventilation. METHODS After 3 days of unsuccessful attempts at weaning from ventilatory support, 10 trauma and surgical patients more than 60 years old were monitored daily. Previously reported predictors of the duration of mechanical ventilation and weaning outcome were measured, including hemodynamic and gas exchange variables, oxygen cost of breathing, and the score on the Burns Weaning Assessment Program. RESULTS The 6 patients who could be weaned from ventilatory support were younger (median age, 71.5 years) than the 4 patients who could not be weaned (median age, 80 years). Patients who could be weaned were ready for weaning by day 11 of their stay in the intensive care unit and required an additional 5.5 days of mechanical ventilation; those who could not be weaned were not ready for weaning until day 17. All patients initially had increases in oxygen consumption during weaning; those who were successfully weaned had decreases before extubation. Respiratory rate, maximal inspiratory pressure, the ratio of Pao2 to fraction of inspired oxygen, and mean arterial pressure were higher in patients who could be weaned, and oxygen cost of breathing and central venous pressure were lower CONCLUSION Further study of weaning in older adults is warranted.