Effectiveness of inspiratory muscle training on respiratory fitness and breathlessness in chronic renal failure: A randomized control trial.

BACKGROUND: People with chronic renal failure (CRF) show decreased respiratory fitness and poor quality of life (QOL). Exercise during hemodialysis has been suggested to improve the cardio-respiratory fitness. However, results of effects of respiratory muscle (RM) training on respiratory fitness and QOL are inconsistent. In addition, very few studies explored the association between inspiratory muscle (IM) training and sensation of breathlessness. OBJECTIVES: To examine the effects of IM training in hemodialysis patients on respiratory fitness QOL and breathlessness. METHOD: A randomized control trial with 50 CRF, who underwent hemodialysis (25 individuals in each group; IM training and sham group) was designed. Pulmonary function, RM strength, QOL (measured by Kidney Disease Quality of Life-36), and sensation of breathlessness were measured before and after an 8-week intervention. RESULTS: Compared to the sham group, the IM strength increased in the intervention group after an 8-week program (Δ25.92 ± 8.73 cmH2 O, p = 0.005). Significantly increased IM and forced vital capacity values in training groups was observed after an 8-week intervention (Δ12.44 ± 3.07 cmH2 O and Δ0.097 ± 0.046 L, respectively), but not the sham group. Neither, the training group, nor the sham group were significantly different in the QOL. However, feeling of shortness of breath improved after the training program among inspiratory muscle training group, but not the sham group. CONCLUSION: IM training during hemodialysis could lead to an improvement of respiratory fitness and reduce breathlessness in people with CRF who are receiving hemodialysis. However, QOL was not different after the training program. The study suggests that after 8-week intervention program, IM training (loading exercise) could improve IM strength, pulmonary function without any complications during the intervention program within 1-2 h.

Duration of hemodialysis associated with cardio-respiratory dysfunction and breathlessness: a multicenter study.

BACKGROUND: Patients with hemodialysis suffer with protein-energy wasting and uremic myopathy lead to lack of physical activity and poor functional performance. However, ventilation abnormality in patients undergone hemodialysis remains controversial regarding the respiratory impairment. Therefore, the study aimed to determine the effect of duration of dialysis on respiratory function. METHODS: A multicenter study with cross-sectional study was designed in four hemodialysis outpatient clinics. Respiratory muscle strength (i.e., maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP)) pulmonary function test (i.e., forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and FEV1/FVC ratio), functional capacity (6-minute walk test) and sensation of breathlessness were assessed prior to dialysis. RESULTS: A total of 100 hemodialysis patients were recruited with 38 females and 62 males. An average of duration of hemodialysis was 5.93± 4.96 years. Decreased MIP values, FEV1 values, FVC values, %FEV1 and %FVC were noted in patients with long duration of dialysis (defined as ≥ 5 years of dialysis) compared to those with short duration of dialysis (ps < .05). In addition, increased sensation of breathlessness was observed in patients with long duration of dialysis (p < .05). Furthermore, participants with long duration of dialysis had an increased risk of ventilatory restriction (OR 6.093, p = .007).