title: Respiratory biofeedback accuracy in chronic renal failure patients: a method comparison.
abstract: OBJECTIVE
  To analyse respiratory biofeedback effects on respiratory muscle strengthening in chronic renal failure patients.
  
  
  METHODS
  Randomized controlled study.
  
  
  METHODS
  Nephrology and dialysis centre.
  
  
  METHODS
  Forty-one end-stage renal patients on haemodialysis treatment were allocated into three groups: control (n = 10), G-1 (inspiratory muscle training using Threshold IMT device; n = 16) and G-2 (biofeedback; n = 15) and given respiratory muscle training (three sessions/week for six weeks).
  
  
  METHODS
  Forced vital capacity (FVC), expiratory volume in the first second (FEV(1)), FEV(1)/FVC ratio, maximal voluntary ventilation (MVV) and maximal inspiratory (MIP) and expiratory (MEP) pressures were measured before and after the respiratory muscle training programme.
  
  
  RESULTS
  Both training methods were efficient since we found an increase after training in the FVC in the G-1 group (from 2.45 ± 0.17 to 2.85 ± 0.16; P = 0.001) and in the G-2 group (from 2.35 ± 0.19 to 2.55 ± 0.19; P = 0.007), in the FEV(1) in G-1 (from 2.18 ± 0.16 to 2.46 ± 0.14; P = 0.01) and in G-2 (from 1.97 ± 0.17 to 2.20 ± 0.15; P < 0.0001), MIP in G-1 (from 70.63 ± 4.03 to 108.75 ± 7.41; P < 0.0001) and in G-2 (from 67.67 ± 5.02 to 96.33 ± 8.30; P < 0.001) and MEP in G-1 (from 73.13 ± 5.10 to 82.50 ± 6.74; P = 0.007) and in G-2 (from 67.67 ± 5.41 to 76.00 ± 4.29; P = 0.002).
  
  
  CONCLUSIONS
  Respiratory biofeedback is efficient as a respiratory muscle training modality for patients with chronic renal failure.
authors.affiliation: Santa Terezinha University, CEST-MA, Brazil. roy_figueiredo@yahoo.com.br
authors.forename: Rogério Ramos
authors.initials: RR
authors.lastname: Figueiredo
authors.forename: Antonio A M
authors.initials: AA
authors.lastname: Castro
authors.forename: Fernanda M G Gonzaga
authors.initials: FM
authors.lastname: Napoleone
authors.forename: Leina
authors.initials: L
authors.lastname: Faray
authors.forename: Alderico Rodrigues
authors.initials: AR
authors.lastname: de Paula Júnior
authors.forename: Rodrigo Alexis Lazo
authors.initials: RA
authors.lastname: Osório
mesh_terms: D000328:Adult; D001676:Biofeedback, Psychology / Q000379:methods*; D001945:Breathing Exercises; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D015203:Reproducibility of Results; D012129:Respiratory Function Tests; D012132:Respiratory Muscles / Q000503:physiopathology*