Effects of four different mechanically assisted coughing procedures on pulmonary function in patients with neuromuscular disease

Introduction: Mechanically assisted coughing (MAC) is an airway clearance method in which the thorax and/or the abdomen are compressed in synchronization with mechanical insufflation-exsufflation (MI-E). Aims: The purpose of this study was to examine the effects of four MAC procedures on pulmonary function in different conditions of patients with neuromuscular disease (NMD). Methods: Twenty-seven patients (mean age, 54.3 ± 18.8 years) with NMD (PMD=15, ALS=6, other=6) who underwent MI-E were divided into an air stacking group, a no air stacking group, and a tracheostomy positive pressure ventilation(TPPV) group. MAC procedures were divided into the following four groups according to the position of manual assistance: MI-E alone, upper thoracic MAC (UT-MAC), lower thoracic MAC (LT-MAC), and upper thoracic/abdominal MAC (UT/A-MAC). Pulmonary function was evaluated by cough peak flow (CPF) and the value at 75% of the forced vital capacity (V75). Results: In the air stacking group, CPF with MI-E alone was significantly lower than CPF with UT-MAC, LT-MAC, and UT/A-MAC (p Conclusions: In the air stacking group, a higher CPF was achieved with MAC compared with MI-E. However, the effect of MAC was influenced by the position of manual assistance and the presence of scoliosis. MAC did not increase CPF in NMD patients with TPPV.