Survival of mechanically ventilated patients admitted to a specialised weaning centre.

OBJECTIVE

Hospital mortality and survival rates of long-term ventilated patients.DESIGN. Retrospective cohort study.

SETTING

Specialised national weaning centre.

INTERVENTION

Protocol-directed liberation from ventilator.

PATIENTS

Four hundred three of 640 patients with prolonged mechanical ventilation (MV) who were admitted to our respiratory intensive care unit (RICU) were studied. MV lasted longer than 2 weeks and patients had failed more than two weaning trials in the referring ICUs. The majority of patients (59.3%) had chronic obstructive pulmonary disease (COPD).

RESULTS

After a mean duration of 41 days of MV prior to transfer, 68% of patients were liberated from the ventilator. In total, 98 of 403 patients (24.3%) died during the stay in our hospital, 305 patients (75.7%) were discharged. Compared to the non-survivors, the survivors were characterised by younger age, longer length of stay in our RICU, lower severity of illness scores at admission, fewer cardiac illnesses and a higher rate of weaning success. In 31.5% of the discharged patients non-invasive MV (NIV) was initiated during the stay at our unit. We gathered follow-up data on 293 patients (96.1%). Post-discharge survival rates were 67.6% at 3 months, 49.4% at 1 year and 38.1% at 3 years. Length of survival was significantly dependent on age, weaning success and main diagnosis (i.e., prognosis in COPD is worse compared to thoracic restriction, neuromuscular disease and others) in the multivariate analysis.

CONCLUSIONS

Difficult-to-wean patients have a high hospital mortality rate and poor long-term prognosis. Age, main diagnosis, severity of illness, weaning success and institution of NIV predict survival.