External control of exhalation for cough assistance: a method for patients with glottis dysfunction and/or tracheostomy.

OBJECTIVE

To investigate the effectiveness of our method of assisting a cough by mimicking the functions of the glottis in patients with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube.

DESIGN

Before-after trial.

SETTING

University rehabilitation hospital.

PARTICIPANTS

Patients (N=35) with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube.

INTERVENTIONS: Not applicable.

MAIN OUTCOME MEASURES: The unassisted peak cough flow (PCF), the assisted PCF, and the assisted PCF with the external control method mimicking glottis function by an end-inspiratory external closure of the airways.

RESULTS

Of the 35 patients, 13 were tracheostomized cervical cord injury patients, 11 were neuromuscular disease (NMD) patients with glottis dysfunction only, and 11 were NMD patients with a tracheostomy and glottis dysfunction. Assisted PCF with the external control method were higher than unassisted PCF and/or assisted PCF in all patients. Assisted PCF with the external control methods were measured in all of the patients even when the unassisted PCFs and/or assisted PCFs could not be measured. For patients with measurable assisted PCFs, the assisted PCF with the external control methods were significantly higher than the assisted PCFs.

CONCLUSIONS

We showed the effectiveness of our method of assisting a cough by external control of the glottis in patients with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube who cannot effectively cough with the help of existing cough assistance methods.