The INTEGRATION Study
Inspiratory Work of Breathing Before and After Extubation
Study Investigators
Samira Fard (samira.fard@uhn.ca)
Dr. Ewan Goligher (ext. 6810, ewan.goligher@uhn.ca)
Study Contact
Samira Fard (samira.fard@uhn.ca)
Study Summary
Prospective observational study aiming to characterize in detail the effects of zero end expiratory pressure (ZEEP) during spontaneous breathing trial on lung lung volume and post-inspiratory work of breathing.
Study Population
We will enrol 30 patients intubated and mechanically ventilated patients, 15 lung transplant patients and 15 patients who have been admitted to the medical-surgical intensive care unit requiring invasive mechanical ventilation for any reason.
Study Objectives
To determine whether end-expiratory lung volume and respiratory effort vary between zero airway pressure with endotracheal intubation in comparison post-extubation.
To determine whether expiratory braking (post-inspiratory effort) acts to maintain lung volume when airway pressure is reduced to zero in endotracheally intubated patients.
Study Interventions
Once the patient has completed the spontaneous breathing trial (SBT) and the healthcare team decides it is safe to extubate, the patients will undergo brief SBTs of continuous positive airway pressure (CPAP) of 5 cmH2O and ZEEP before extubation. Patients will undergo both trials for 15 minutes; we will lung volume during both SBTs and 30 minutes after the breathing tube has been removed. We will utilize electrical impedance tomography (EIT) to showcase how end expiratory lung volume (EELV) are affected and assess for expiratory braking by measuring negative inspiratory work on Campbell diagram during SBTs and post extubation.
Why it Matters
There are various spontaneous breathing trials strategies (ZEEP and CPAP of 5 cmH2O) that impact both gas exchange and the work of breathing (WOB) before and after extubation. By using this new bedside imaging (EIT), it will help inform and increase more evidence on the benefits of using ZEEP SBT trial. The Campbell diagram, which commonly not utilized, is another method to quantify post inspiratory work of breathing of the respiratory muscle and diaphragm during the three different scenarios. With the use of the Campbell Diagram, we will be able to establish and quantify the existence of expiratory braking during SBT trial and post extubation, and in the final analysis determine its influence on the outcome of extubation.