Effects of daily inspiratory muscle training on respiratory muscle strength and chest wall regional volumes in haemodialysis patients: a randomised clinical trial

Abstract

Purpose: Evaluating the effects of interdialytic daily inspiratory muscle training (IMT) on respiratory muscle strength, chest wall regional volumes, diaphragmatic mobility and thickness, pulmonary function, functional capacity, and quality of life (QoL) in haemodialysis (HD) patients.Method: A randomised, and double-blind clinical trial composed of 24 chronic kidney disease patients undergoing HD. Patients were allocated into the IMT group (n = 12) or sham group (n = 12) and performed daily IMT twice per day with a load of 50% inspiratory muscle strength for the IMT group and 5 cmH2O for the sham group during 8 weeks. Respiratory muscle strength, diaphragm thickness and mobility, chest wall regional volumes, functional capacity, and QoL were measured.Results: At the end of the study, an increase in inspiratory and expiratory muscle strength was observed for both groups, but no significant difference was found between them. Changed volume distribution was also observed in the IMT group, with significantly increased inspiratory capacity in the pulmonary compartment compared to the sham group.Conclusions: Daily interdialytic IMT promoted a change in chest wall regional volumes, with an increase in the inspiratory capacity of the pulmonary rib cage. Both groups had increased inspiratory and expiratory muscle strength with daily respiratory exercise.Trial registration: www.ClinicalTrials.gov; study number: NCT02599987; name of trial registry: IMT in Patients with End-stage Renal Disease.Implications for rehabilitationMuscular impairment in chronic kidney disease patients results from a series of common alterations, affecting respiratory muscles.Patients with chronic kidney disease have low values of diaphragmatic thickness.The daily inspiratory muscle training (IMT) or breathing exercise over a period of 8 weeks provided increased respiratory muscle strength.The daily inspiratory muscle training presented a change in tri-compartment distribution of lung volume compared to the sham group, with increased inspiratory capacity of the pulmonary rib cage.