Background:The treatment of patients with COPD and chronic hypercapnic respiratory failure using non-invasive home ventilation (NIV) is well established. A "deventilation syndrome" (DVS) has been described as dyspnea after cessation of NIV therapy.
Methods:A systematic scoping review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews searching Embase was conducted. A final manual search followed in February 2023. Literature synthesis was blinded using Rayyan by three different reviewers.
Results:A total of 2009 studies were screened. 5 studies met the eligibility criteria. 4 articles presented original data. 3 articles examined treatment options. 3 studies were prospective; none were randomized. A total of 122 patients were included. DVS was defined differently in all studies. 74 patients had DVS (48 controls). Patients were evaluated by blood gas analysis, transcutaneous PCO2, spirometry, body plethysmography, respiratory muscle assessments, diaphragmatic EMG and ultrasound, 6-minute walk test, polysomnography, and questionnaires. Treatment approaches included minimization of patient ventilator asynchrony (PVA) and use of pursed lip breathing ventilation. Pathophysiologic mechanisms discussed were PVA, high IPAP, hyperinflation and respiratory muscle impairment. Compared with controls, patients with DVS suffered from more severe airway obstruction, hyperinflation, and PaCO2 retention, worse exercise test scores and poorer quality of life.
Conclusion:The available evidence does not allow for definite conclusions about pathophysiological mechanisms, ethology, or therapeutic options.