Diaphragm sonography as an educational aid in CPAP and NIMV treatment

Background: During the use of CPAP ( Continuos Positive Airway Pressure), with contained pressures, the excursion of the diaphragm tends to increase. Conversely during NIMV ( Non Invasive Mechanical Ventilation ), with the increase in pressure support, there is a decrease in work of breathing (WOB) and in diaphragm excursion. Aims: The purpose of the study was to evaluate whether diaphragm sonography could be a useful aid to promote adaptation during the ventilation of patients in CPAP or NIV who have difficulty on accepting this treatment. Methods: We studied the diaphragmatic excursion of 20 patients using a portable sonography with a convex probe from 1 to 5 MgHz. The patient9s position was generally supine at 45°. The probe was placed in the right subcostal position (the window of the liver is  larger than that of the spleen). The patient breathes spontaneously and the machine record the excursion from the maximum inspiratory point to the lowest expiratory point. The monitor was turned towards the patient9s face so he can see what happens during each breath.Subsequently the patient was vented with nasal or oronasal mask and the measurement was remade during CPAP/NIMV ventilation. The modification, breath on breath, of the diaphragmatic excursions, seen by the patient live, facilitated the approach to the use of the ventilatory device. Results: All 20 patients evaluated with this method accepted more easily to use the ventilator device. Conclusion: The Diaphragm sonography can be an excellent, safe, fast, not expensive method to be performed, at the patient9s bed, to reinforce an respiratory educational program in patient9s with problem9s of adaptation to CPAP/NIMV ventilation.