Mechanical Insufflation-Exsufflation in Critically Ill Patients: An International DELphi Consensus (DELMI-E)

Background: Mechanical insufflation-exsufflation (MI-E) functions as a noninvasive method which clears airways through its ability to enhance cough performance by delivering positive pressure to initiate airflow and then rapidly applies negative pressure for exhalation. MI-E enables bronchial secretions to be moved and eliminated through its ability to produce high expiratory flows while decreasing the chances of secretions being retained in the lungs.

MI-E is well established in patients with neuromuscular diseases and chronic respiratory disorders, in which weak cough and airway clearance dysfunction are the main contributors to respiratory morbidity. Nevertheless, the use of this technique in critically ill patients, particularly those admitted to the intensive care unit (ICU), is still diverse and insufficiently standardized. Invasive and non invasive ventilation, sedation, impaired consciousness, artificial airways, and respiratory muscle dysfunction substantially alter cough physiology in ICU patients, increasing risk of secretion retention, atelectasis, extubation failure, and reintubation.

Research on MI-E applications for ICU patients has become more popular but current clinical practices show different standards for selecting patients and determining treatment times and establishing device settings and conducting safety checks and managing restricted treatment conditions and integrating MI-E use with other ventilation modalities. A few studies available are restricted by small sample sizes, mixed populations, and varying outcome definitions, thus no clear recommendations can be made. Concerns about safety, such as the risk of barotrauma and damage to the airway, changes in clinical practice, and the requirement for staff skills and training are some of the factors that cause uncertainty and inconsistency in the use of MI-E in critically ill patients.

In situations where there are few high-quality randomized trials giving the evidence, expert consensus is now generally considered to be a proper and effective methodology to determine clinical best practice. The Delphi method with the addition of fuzzy logic is a way of systematically collecting and combining the experts' opinions, and it also counteracts the influence of the strongest participants and allows the identification of the recommendations that should be given priority, both from the point of view of their clinical relevance and of their feasibility.

Therefore, it is necessary to carry out a global, multidisciplinary Delphi consensus study in order to identify best practices and agree on consensus, based guidelines for implementing MI-E therapy in critical care patients.