Table 4 Research on the effect on cough ability of cough assist machines and manual thrust on abdominal muscles

Kim et al. 24

Patients with noninvasive ventilator-dependent neuromuscular disease

Comparisons of the effects of unassisted, manually assisted following a maximum insufflation capacity (MIC) maneuver, assisted by mechanical in-exsufflator (MI-E), or assisted by manual thrust plus MI-E on peak cough flow (PCF)

The PCF (L/min) was 95.7 (40.5) when unassisted, 155.9 (53.1) when manually assisted following an MIC maneuver, 177.2 (33.9) when assisted by MI-E, and 202.4 (46.6) when assisted by manual thrust plus MI-E*

FVC (ml): 667.4 ± 313.4, improvement of 17.9%; MIP: 19.5 ± 10.2 cmH₂O, improvement of 19.1%; MEP: 25.3 ± 19.6 cmH₂O, improvement of 16.0%

Lacombe et al. 25

Neuromuscular patients

Comparison of three cough-augmentation techniques: insufflation by intermittent positive-pressure breathing (IPPB) combined with manually assisted coughing (MAC), mechanical insufflation-exsufflation (MI-E), and MI-E + MAC

Visual analog scale:

Comfort: 6.4 vs 7.0 vs 6.6

Effectiveness: 6.4 vs 8.3*vs 8.5*

All three methods are ineffective: PCF > 4 L/s, average expiratory pressure is 40 cmH₂O

Sivasothy et al. 23

9 normal subjects, 8 patients with chronic obstructive pulmonary disease (COPD), 12 with neuromuscular diseases (including 4 subjects with respiratory muscle weakness (RMW) with scoliosis, and 8 subjects with RMW without scoliosis)

Comparing manually assisted cough and mechanical insufflation

There was no difference in peak cough flow (PCF) and cough expiratory volume (CEV) in normal subjects. PCF: Normal: 668 → 624; COPD: 370 → 245*(CEV/L, PVT/ms: 0.8, 40); scoliosis with RMW:288 → 362(CEV/L, PVT/ms:0.6, 50); RMW:104 → 248*(CEV/L, PVT/ms:0.6, 75)

Liu et al.

Long-term ventilator patients

Comparing cough reinforcement methods: unassisted, abdominal weight training (AWT), cough machine assisted abdominal weight training (AWT + CM)

In the AWT + CM group, the maximum inspiratory pressure (MIP) improved by 21%, the maximum expiratory pressure (MEP) improved by 55%, and the peak expiratory flow (PCF) improved by 21%

There was a 27% improvement in VC (p = 0.023)