Transdiaphragmatic Pressure and Neural Respiratory Drive Measured During Inspiratory Muscle Training in COPD
Condition: Chronic Obstructive Pulmonary Disease
MeSH terms: Lung Diseases, Obstructive; Pulmonary Disease, Chronic Obstructive
Study type: Interventional

Summary: 
      Inspiratory muscle training（IMT）was an rehabilitation therapy for stable patients with
      chronic obstructive pulmonary disease(COPD). However, its therapeutic effect remains
      undefined due to unclear of diaphragmatic mobilization during IMT. Diaphragmatic mobilization
      represented by transdiaphragmatic pressure（Pdi）and neural respiratory drive expressed as
      corrective root-mean-square(RMS) of diaphragmatic electromyogram(EMGdi) provide vital
      information to select the proper IMT device and loads in COPD, therefore make curative effect
      of IMT clarity. Pdi and RMS of diaphragmatic electromyogram (RMSdi%) was respectively
      measured and compared during inspiratory resistive training and threshold load training in
      stable patients of COPD.
    

Detailed description: 
      Subjects：The diagnosis and severity of all participants were measured using the pulmonary
      function test according to Global Initiative for Chronic Obstructive Lung Disease.

      Inclusion criteria: (1)Severe and very severe COPD (postbronchodilator FEV1/FVC under 70% and
      FEV1 under 50% of the predicted value (GOLD C and D group); (2)Inspiratory muscle
      weakness（Maximal Inspiratory Pressure under 60cmH2O）; (3) Bronchial dilation test (BDT)
      negative.

      Exclusion criteria: (1) acute exacerbation in the previous 4 weeks; (2) using the oral
      corticosteroids within4 weeks; (3) history of other respiratory, cardiovascular,
      neuromuscular, musculoskeletal diseases that could interfere the study.

      Study design This was a single-centre, cross-sectional study.

      Intervention： Inspiratory resistive training All participants conducted inspiratory resistive
      training using inspiratory resistive trainer (PFLEX, Respironics Inc, USA). Pdi and EMGdi
      were recorded synchronously.Inspiratory resistive load was change from low intensity into
      moderate and high intensity randomly（inspiratory hole diameters was set to 5.3mm, 2.4mm and
      1.8mm,respectively）

      Inspiratory threshold load training Inspiratory threshold load training was conducted by all
      participants using the inspiratory threshold load trainer (Threshold Inspiration Muscle
      Trainer, Respironics Inc, USA) .Inspiratory threshold pressure was set to low, medium and
      high intensity randomly（threshold pressure was 30%,60% and 80% of MIP, respectively).

      Measurements ：transdiaphragmatic pressure and neural respiratory drive
    

Intervention name(s): Threshold IMT®; PFLEX®
Intervention type(s): Device; Device
Intervention description(s): A device used to offer threshold load to inspiratory muscle; A device used to offer resisive to inspiratory muscle
Other intervention name(s): inspiratory threshold load inspiratory muscle training; inspiratory resisive inspiratory muscle training
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Treatment