Effects Of Mechanical In-Exsufflation On Mucus Clearance In Critically Ill Patients On Invasive Mechanical Ventilation

Abstract Background: Mechanical insufflation-exsufflation (MI-E) is a non-invasive technique performed through the CoughAssist In-Exsufflator to simulate cough and remove mucus from proximal airways. To date, the effects of MI-E on critically ill patients on invasive mechanical ventilation (MV) are not fully elucidated. The purpose of this study was to compare the efficacy and safety of MI-E combined or not to manual chest physiotherapy (CPT) in these patients.Methods: This cross-over clinical study enrolled consecutive patients who were sedated, intubated and on MV > 48h with expected maintenance of these criteria > 24h. Over a 24-hour period, patients randomly performed two sessions of manual CPT with or without additional MI-E before tracheal suctioning. Following each procedure, volume of retrieved mucus (ml) was assessed to evaluate efficacy. We evaluated respiratory flows, pulmonary mechanics and hemodynamics before, during, and after treatment. In addition, safety of MI-E was also appraised.Results: 26 patients were included. In comparison to CPT, mucus volume retrieved was significantly higher during CPT+MI-E (0.42 [0; 1.39] ml vs 2.29 [1; 4.67] ml; p < 0.001). The respiratory system compliance immediately improved from pre and post Crs values in CPT+MI-E group (55.7 ml/cmH2O [38.3; 67.4] vs. 68.6ml/cmH2O [47.8;94.9]; p<0.001). Although, such increase was not significantly different between CPT and CPT+MI-E group (p=0.057). Heart rate significantly increased in both groups (p < 0.005) immediately after each intervention. Additionally, a significant impact on oxygenation was observed in the CPT+MI-E group when comparing the baseline values with the values one-hour post-intervention (p<0.05). Finally, several transitory hemodynamic variations occurred during both interventions, but these were non-significant and considered clinically irrelevant.Conclusion: In mechanically ventilated patients, MI-E increases the amount of secretions that can be retrieved post-CPT, without causing clinically significant adverse events.Clinical Trials Registration Number: NCT03316079 (24/11/2015; retrospectively registered)