Number of subjects The calculation of the number of subjects is based on two retrospective studies. In the study by VIANELLO, which included 11 adults hospitalized in the ICU for respiratory failure, the number of therapeutic failures, defined as the need for a "mini" tracheotomy or intubation, was significantly less in the group using MI-E than in a group of 16 historical control patients [2 failures in the MI-E group (18%) versus 10 failures in the control group (63%), p<0.05] (1). Another study reported 19 successes (80%) versus 5 failures on MI-E (2).