[The effect of spontaneous breathing trial on weaning from ventilators]

To investigate whether spontaneous breathing trial is an essential process during weaning from ventilator in critically cared patients without chronic obstructive pulmonary disease (COPD).

The study was performed with a prospective, randomized, double-blinded method. A total of 67 adult patients, mechanically ventilated for at least 48 h in SICU of a teaching hospital, were enrolled. As soon as the patients were ready for weaning from ventilators, they were randomly assigned to 2 groups with target extubation without spontaneous breathing trial (SBT) (non-SBT group) and with SBT (SBT group). In the SBT group, the patient who tolerated the spontaneous breathing trial underwent immediate extubation. In the non-SBT group, as soon as a patient met weaning readiness criteria, he or she underwent extubation without SBT process. The primary outcome measure was successful extubation, defined as the ability to maintain spontaneous breathing for 48 hrs after extubation. Results were expressed as mean +/- SD. Mean values between the 2 groups were compared by student's t tests. The differences in proportions between the 2 groups were determined using chi(2)-test.

There were no significant differences in demographic, respiratory, and hemodynamic characteristics between the 2 groups at the end of assessing weaning readiness criteria. Three (9.7%) patients in the SBT group and 3 (9.4%) patients in the non-SBT group needed reintubation (chi(2) = 0.013, P = 0.908). Five patients in the non-SBT group and 4 in the SBT group required noninvasive ventilation following extubation (chi(2) = 0.253, P = 0.727). There were no significant differences in in-hospital mortality between the 2 groups (chi(2) = 0.276, P = 0.600).

The result suggests that spontaneous breathing trial may be not a necessary procedure preceding extubation in a general intensive care population.