title: Abdominal muscle training can enhance cough after spinal cord injury.
abstract: BACKGROUND
  Respiratory complications in people with high-level spinal cord injury (SCI) are a major cause of morbidity and mortality, particularly because of a reduced ability to cough as a result of abdominal muscle paralysis.
  
  
  OBJECTIVE
  . We investigated the effect of cough training combined with functional electrical stimulation (FES) over the abdominal muscles for 6 weeks to observe whether training could improve cough strength.
  
  
  METHODS
  Fifteen SCI subjects (C4-T5) trained for 6 weeks, 5 days per week (5 sets of 10 coughs per day) in a randomized crossover design study. Subjects coughed voluntarily at the same time as a train of electrical stimulation was delivered over the abdominal muscles via posterolaterally positioned electrodes (50 Hz, 3 seconds). Measurements were made of esophageal (Pes) and gastric (Pga) expiratory pressures and the peak expiratory flow (PEFcough) produced at the 3 time points of before, during, and after the training.
  
  
  RESULTS
  During voluntary coughs, FES cough stimulation improved Pga, Pes, and PEFcough acutely, 20-fold, 4-fold, and 50%, respectively. Six weeks of cough training significantly increased Pga (37.1 ± 2.0 to 46.5 ± 2.9 cm H2O), Pes (35.4 ± 2.7 to 48.1 ± 2.9 cm H2O), and PEFcough (3.1 ± 0.1 to 3.6 ± 0.1 L/s). Cough training also improved pressures and flow during voluntary unstimulated coughs.
  
  
  CONCLUSIONS
  FES of abdominal muscles acutely increases mechanical output in coughing in high-level SCI subjects. Six weeks of cough training further increases gastric and esophageal cough pressures and expiratory cough flow during stimulated cough maneuvers.
authors.affiliation: 1Neuroscience Research Australia, Randwick, New South Wales, Australia.
authors.forename: Rachel A
authors.initials: RA
authors.lastname: McBain
authors.forename: Claire L
authors.initials: CL
authors.lastname: Boswell-Ruys
authors.forename: Bonsan B
authors.initials: BB
authors.lastname: Lee
authors.forename: Simon C
authors.initials: SC
authors.lastname: Gandevia
authors.forename: Jane E
authors.initials: JE
authors.lastname: Butler
mesh_terms: D000009:Abdominal Muscles / Q000503:physiopathology*; D000328:Adult; D000368:Aged; D001945:Breathing Exercises; D002574:Cervical Vertebrae; D003131:Combined Modality Therapy; D003371:Cough / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D018592:Cross-Over Studies; D004599:Electric Stimulation Therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function; D013119:Spinal Cord Injuries / Q000150:complications / Q000534:rehabilitation*; D013904:Thoracic Vertebrae; D055815:Young Adult
keywords: abdominal muscle training; functional electrical stimulation; spinal cord injury; stimulated cough