Spontaneous breathing trial reduces mechanical ventilation weaning when compared with SmartCare™ ventilation

Introduction

Mechanical ventilation (MV) weaning is commonly performed using a spontaneous breathing trial (SBT) with pressure support ventilation after a daily weaning screen [1]. Recently there has been increased interest in automatic weaning trials, using respiratory rate, tidal volume and ETCO₂ monitoring during SBT [1, 2]. So far there is no clinical evidence comparing an automatic weaning trial with SBT. Our study's objective was to compare MV and weaning times between Automatic Weaning Ventilation System (SmartCare™/PS) and SBT groups.

Methods

A randomized, controlled study was performed in a general ICU. We enrolled adult patients who were ventilated for more than 24 hours. Patients were randomized either to the control or SmartCare™ group. All patients were ventilated with a Drager EvitaXL (Drager Medical, Lubeck, Germany) ventilator with SmartCare™/PS software version 1.1. The control group consisted of a daily weaning screen and SBT with pressure support ventilation; if patients tolerated SBT they were extubated. SmartCare™ group patients were also submitted to a daily weaning screen, after which they were ventilated with the SmartCare™/PS mode. We evaluated the MV and weaning time, maximum inspiratory pressure, maximum expiratory pressure, vital capacity, respiratory frequency to tidal volume ratio (f/Vt), use of noninvasive ventilation (NIV) post extubation, and re-intubation rate.

Results

We evaluated a total of 70 patients (35 patients randomized in each group). There was no difference in age (P = 0.298) or gender (P = 0.08) between groups (Table 1). There was no difference in MV time between the control and SmartCare group (P = 0.534) (Table 1). Weaning duration was lower in the control group (pf/VT, P = 0.414), use of NIV post extubation (P = 0.811) and re-intubation rate (P = 1.0) (Table 1).

Table 1 Characteristics of patients between SmartCare™ and control groups

Conclusion

SBT showed a reduction in weaning time when compared with the SmartCare™/PS group, although there was no impact on total MV time and reintubation rate.