Patient-ventilator Asynchrony in Conventional Ventilation Modes During Short-term Mechanical Ventilation After Cardiac Surgery
Condition: Thoracic Surgery
Study type: Interventional

Summary: 
      This study evaluates the effects of VCV, PCV and PSV ventilatory modes during the immediate
      postoperative period on the variables resulting from regional and global pulmonary electrical
      impedance and diaphragmatic mobility, as well as perform ventilator synchrony analysis in PSV
      mode by mechanical ventilator. Half of the participants will receive VCV followed by PSV for
      weaning, while the other half will receive PCV followed by PSV for weaning.
    

Detailed description: 
      In the immediate postoperative period of cardiac surgery, patients are found under mechanical
      ventilatory support. Commonly, they are ventilated in controlled and assisted-controlled
      volume (VCV) or pressure (PCV) modes, with weaning at pressure support (PSV).

      Systematic reviews indicate that there is no difference between the VCV and PCV ventilatory
      modes for some clinical outcomes or that the existing evidence is insufficient. The
      distribution of regional ventilation and diaphragmatic mobility can be measured from the use
      of electrical impedance tomography (EIT) and diaphragmatic ultrasonography (US) to clarify
      the physiological changes and / or mechanisms of adaptation of the organism submitted to
      controlled modes cycled at volume or at pressure and spontaneously flow cycled mode.

      Besides EIT and US measures, gasometric, hemodynamic and respiratory data will also be
      recorded. The statistical analysis will be considered α≤0.05 for a statistically significant
      difference.
    

Intervention name(s): VCV+PSV; PCV+PSV
Intervention type(s): Device; Device
Intervention description(s): invasive mechanical mechanical modes by volume cycling and by pressure support which the patients will be submitted to before weaning. Post-operative mechanical ventilation average time: 6 hours after ICU admission.; invasive mechanical mechanical modes by pressure cycling and by pressure support which the patients will be submitted to before weaning. Post-operative mechanical ventilation average time: 6 hours after ICU admission.
Other intervention name(s): volume controlled ventilation mode; pressure support ventilation mode; pressure controlled ventilation mode; pressure support mode
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: A parallel group study is a simple and commonly used clinical design which compares two treatments. Usually a test therapy is compared with a standard therapy. The allocation of subjects to groups is usually achieved by randomisation. The groups are typically named the treatment group and the control group. Parallel group designs do not require the same number of subjects in each group, although often similar numbers are observed. The design is commonly used in randomised controlled trials. Statistical analysis often boils down to a simple t-test of the between group difference in the outcome, which is usually a mean or a proportion.
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Diagnostic