Long-term mortality and quality of life after prolonged mechanical ventilation

Abstract

Objective: To describe and identify factors associated with mortality rate and quality of life 1 yr after prolonged mechanical ventilation.

Design: Prospective, observational cohort study with patient recruitment over 26 months and follow-up for 1 yr.

Setting: Intensive care units at a tertiary care university hospital.

Patients: Adult patients receiving prolonged mechanical ventilation.

Interventions: None.

Measurements and main results: We measured mortality rate and functional status, defined as the inability to perform instrumental activities of daily living (IADLs) 1 yr following prolonged mechanical ventilation. The study enrolled 817 patients. Their median age was 65 yrs, 46% were women, and 44% were alive at 1 yr. Median ages at baseline of 1-yr survivors and nonsurvivors were 53 and 71 yrs, respectively. At the time of admission to the hospital, survivors had fewer comorbidities, lower severity of illness score, and less dependence compared with nonsurvivors. Severity of illness on admission to the intensive care unit and prehospitalization functional status had a significant association with short-term mortality rate, whereas age and comorbidities were related to long-term mortality. Fifty-seven percent of the surviving patients needed caregiver assistance at 1 yr of follow-up. The odds of having IADL dependence at 1-yr among survivors was greater in older patients (odds ratio 1.04 for 1-yr increase in age) and those with IADL dependence before hospitalization (odds ratio 2.27).

Conclusions: Mortality rate after prolonged mechanical ventilation is high. Long-term mortality rate is associated with older age and poor prehospitalization functional status. Many survivors needed assistance after discharge from the hospital, and more than half still required caregiver assistance at 1 yr. Interventions providing support for caregivers and patients may improve the functional status and quality of life of both groups and thus need to be evaluated.