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Purpose: Mechanically assisted coughing (MAC) is an airway clearance method in which the thorax/abdomen is compressed in synchronization with mechanical insufflation-exsufflation (MI-E). MAC can be performed with manual assistance at the upper thorax (MAC-UT), lower thorax (MAC-LT), and upper thorax + abdomen (MAC-UT/A). This study aimed to determine the most effective approach under different conditions (air stacking or tracheostomy) in patients with neuromuscular disorders (NMDs). Methods: The study included 34 patients with NMDs. The patients were categorized into air stacking group (n=15), no air stacking group (n=9), and tracheostomy/tracheostomy positive-pressure ventilation (TPPV) group (n=10). Results: In each group, the cough peak flow (CPF) at 75% of the forced vital capacity (V̇75), V̇50, V̇25, and V̇10 were investigated during the approaches. In the air stacking group, the CPF was higher with MAC-UT, MAC-LT, and MAC-UT/A than with MI-E (p < 0.05). Additionally, V̇75 was higher with MAC-LT and MAC-UT/A than with MI-E (p < 0.05 and p < 0.01, respectively). In the no air stacking group, V̇75 was higher with MAC-UT/A than with MI-E (p < 0.05). In the tracheotomy/TPPV group, there were no significant differences. Conclusions: MAC approaches, especially MAC-LT and MAC-UT/A, are preferred in air stacking patients. However, in tracheostomy/TPPV patients, the CPF might not increase with MAC.

BACKGROUND: Manually-assisted coughing and mechanical insufflation-exsufflation (MI-E) are commonly used in patients with Duchenne muscular dystrophy (DMD). Few studies have compared cough peak flow (CPF) with manually-assisted coughing to other methods, such as MI-E + manually-assisted coughing. In addition, few studies have reported the reliability of the measured CPF values. This study aimed to compare CPF with different cough-assistance methods and to examine the reliability of CPF data. METHODS: The study included 12 subjects with DMD (mean age, 34 ± 8 y). CPF, CPF + manually-assisted coughing (assisted CPF), maximum insufflation capacity (MIC) + CPF (MIC-CPF), MIC + manually-assisted coughing (MIC+assisted CPF), MI-E (MI-E–CPF), and MI-E + assisted CPF were measured. A spirometer was used to compare CPF measurements obtained with each of the cough-assist techniques. The reliability of the measured CPF values was analyzed using Bland-Altman analysis. RESULTS: CPF was 59 ± 34 L/min, assisted CPF was 113 ± 32 L/min, MIC-CPF was 170 ± 30 L/min, MIC+assisted CPF was 224 ± 62 L/min, MI-E–CPF was 199 ± 40 L/min, and MI-E + assisted CPF was 240 ± 38 L/min. A fixed and proportional bias was found in the CPF measurements made with the peak flow meter and the spirometer. The average 95% CI in the difference between peak flow meter, MI-E, and CPF obtained using the spirometer were −7.45 to −1.95 and −1.45 to 4.95, respectively. Test for correlation was r = 0.54 (P CONCLUSION: MI-E + assisted CPF was the highest. The CPF measured with the peak flow meter suggested underestimation.

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.