External Control of Exhalation for Cough Assistance: A Method for Patients With Glottis Dysfunction and/or Tracheostomy

Lee SC, Park JH, Kang S-W, Kim DH, Song SH. External control of exhalation for cough assistance: a method for patients with glottis dysfunction and/or tracheostomy.ObjectiveTo 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.DesignBefore-after trial.SettingUniversity rehabilitation hospital.ParticipantsPatients (N=35) with bulbar muscle weakness or paralysis and/or those who had a tracheostomy tube.InterventionsNot applicable.Main Outcome MeasuresThe 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.ResultsOf 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.ConclusionsWe 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.