Monitoring Intercostal Muscles After Extubation

Mechanical ventilation is a life-saving treatment for critically ill patients who are unable to breathe on their own. At the time of recovery, separation from the ventilator is performed without difficulty for the majority of patients. However, approximately 15% of patients experience extubation failure, i.e. they are re-intubated after extubation within a period of 48 hours to 7 days. Patients who fail extubation are exposed to a longer duration of mechanical ventilation, higher rates of ventilator-acquired pneumonia, higher morbidity, and higher ICU mortality. Therefore, it is of relevant importance for clinicians to identify patients who are at risk of extubation failure as soon as ventilation has been discontinued. However, current clinical assessment has poor predictive performance: some physiological variables can be helpful but can only be obtained invasively using esophageal and gastric catheters. Using ultrasound measurements to assess the activity of the respiratory muscles could be of particular interest for this purpose. By showing an early recruitment of the accessory muscles as well as diaphragm dysfunction or hyperactivity, ultrasounds could help clinicians pay greater attention to such patients and therefore try to apply specific therapeutics. There are several advantages to ultrasounds: they are non-invasive, available in most intensive care units, and previous studies have reported reasonable reliability of the measurements. In the present study, we aim to assess the contractility of the respiratory muscles (diaphragm, intercostal, and sternocleidomastoid) using ultrasounds to identify patients who may be at risk of extubation failure and/or ICU readmission.