DIAPHRAGM STRENGTH AND LUNG VOLUMES

"RESEARCH DESIGN AND METHODS This will be a physiological observational study~Study design. Participants will breathe on CPAP with a ventilator. The investigators will deliver the PNS at PEEP levels of zero cmH2O (baseline EELV), zero cmH2O + an abdominal binder (to reduce lung volume), five cmH2O and ten cmH2O. The abdominal binder will be used to achieve an EELV lower than at baseline. At the end of the protocol another PNS at zero cmH2O (baseline EELV) will be performed. Healthy participants will be exposed to the different levels of PEEP from 2 to 5 minutes before each PNS is performed.~At every PEEP level, relative changes in EELV (∆z) will be measured with Electrical Impedance Tomography (EIT) to record relative changes in EELV and the electrical activity of the costal diaphragm will be measured using surface electromyography"

"RESEARCH DESIGN AND METHODS This will be a physiological observational study~Study design. For patients. The investigators will perform PNS at the patients own mode of ventilation at their clinical level of PEEP (baseline EELV), PEEP of zero cmH2O (if acceptable for 5 minutes), clinical PEEP ± 2 - 4 cmH2O. At the end of the protocol, another stimulation at the clinical level of PEEP (baseline EELV) will be performed. Patients will be exposed to the different levels of PEEP from 2 to 5 minutes before each PNS is performed."