OBJECTIVES: The aim was to investigate whether 2 weeks of inspiratory muscle training (IMT) could preserve respiratory muscle strength in high-risk patients referred for pulmonary resection on the suspicion of or confirmed lung cancer. Secondarily, we investigated the effect of the intervention on the incidence of postoperative pulmonary complications.
METHODS: The study was a single-centre, parallel-group, randomized trial with assessor blinding and intention-to-treat analysis. The intervention group (IG, n = 34) underwent 2 weeks of postoperative IMT twice daily with 2 × 30 breaths on a target intensity of 30% of maximal inspiratory pressure, in addition to standard postoperative physiotherapy. Standard physiotherapy in the control group (CG, n = 34) consisted of breathing exercises, coughing techniques and early mobilization. We measured respiratory muscle strength (maximal inspiratory/expiratory pressure, MIP/MEP), functional performance (6-min walk test), spirometry and peripheral oxygen saturation (SpO2), assessed the day before surgery and again 3-5 days and 2 weeks postoperatively. Postoperative pulmonary complications were evaluated 2 weeks after surgery.
RESULTS: The mean age was 70 ± 8 years and 57.5% were males. Thoracotomy was performed in 48.5% (n = 33) of cases. No effect of the intervention was found regarding MIP, MEP, lung volumes or functional performance at any time point. The overall incidence of pneumonia was 13% (n = 9), with no significant difference between groups [IG 6% (n = 2), CG 21% (n = 7), P = 0.14]. An improved SpO2 was found in the IG on the third and fourth postoperative days (Day 3: IG 93.8 ± 3.4 vs CG 91.9 ± 4.1%, P = 0.058; Day 4: IG 93.5 ± 3.5 vs CG 91 ± 3.9%, P = 0.02). We found no association between surgical procedure (thoracotomy versus thoracoscopy) and respiratory muscle strength, which was recovered in both groups 2 weeks after surgery.
CONCLUSIONS: Two weeks of additional postoperative IMT, compared with standard physiotherapy alone, did not preserve respiratory muscle strength but improved oxygenation in high-risk patients after lung cancer surgery. Respiratory muscle strength recovered in both groups 2 weeks after surgery.
CLINICAL TRIALSGOV ID: NCT01793155.
© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
KEYWORDS: Inspiratory muscle training; Lung cancer; Physiotherapy; Postoperative; Pulmonary complications; Surgery
PMID: 26489835 DOI: 10.1093/ejcts/ezv359

PURPOSE: Gas exchange abnormalities and inspiratory muscle dysfunction are common postoperative pulmonary complications after cardiac surgery. The aim of this study was to investigate the changes in the alveolar arterial oxygen gradients and inspiratory muscle power after preoperative inspiratory muscle training (IMT) followed by postoperative IMT and early mobilization after coronary artery bypass graft surgery.
METHODS: Patients were randomly assigned to the intervention group (n = 20) or the usual care group (n = 20). The intervention group received preoperative IMT by a threshold load inspiratory muscle trainer and education followed by postoperative IMT and early mobilization. The usual care group received preoperative education and postoperative routine physical therapy care. Alveolar-arterial oxygen gradients and oxygen saturation were measured before induction of anesthesia and postoperatively immediately after extubation, at 24 hours, 48 hours, and on day 8 postsurgery. Inspiratory muscle power was measured before surgery, after 48 hours, and on day 8.
RESULTS: Forty male patients underwent coronary artery bypass graft surgery. The intervention group showed significant (P < .05) improvement of alveolar arterial-oxygen gradients and inspiratory muscle power at all measurement points. The mean of inspiratory muscle power at discharge was significantly higher than at baseline but not statistically significantly different from the preoperative measurement.
CONCLUSION: Pre- and postoperative IMT by the threshold load inspiratory muscle trainer resulted in improvement of inspiratory muscle power, alveolar-arterial gradient, and oxygen saturation.
PMID: 28169983 DOI: 10.1097/HCR.0000000000000234

QUESTION: Does inspiratory muscle training improve respiratory muscle strength, functional capacity, lung function and quality of life of patients with chronic kidney disease? Does inspiratory muscle training improve these outcomes more than breathing exercises?
DESIGN: Systematic review and meta-analysis of randomised trials.
PARTICIPANTS: People with chronic kidney disease undergoing dialysis treatment.
OUTCOME MEASURES: The primary outcomes were: maximal inspiratory pressure, maximal expiratory pressure, and distance covered on the 6-minute walk test. The secondary outcomes were: forced vital capacity, forced expiratory volume in the first second (FEV1), and quality of life.
RESULTS: The search identified four eligible studies. The sample consisted of 110 participants. The inspiratory muscle training used a Threshold® or PowerBreathe® device, with a load ranging from 30 to 60% of the maximal inspiratory pressure and lasting from 6 weeks to 6 months. The studies showed moderate to high risk of bias, and the quality of the evidence was rated low or very low, due to the studies' methodological limitations. The meta-analysis showed that inspiratory muscle training significantly improved maximal inspiratory pressure (MD 23 cmH2O, 95% CI 16 to 29) and the 6-minute walk test distance (MD 80m, 95% CI 41 to 119) when compared with controls. Significant benefits in lung function and quality of life were also identified. When compared to breathing exercises, significant benefits were identified in maximal expiratory pressure (MD 6 cmH2O, 95% CI 2 to 10) and FEV1 (MD 0.24litres 95% CI 0.14 to 0.34), but not maximal inspiratory pressure or forced vital capacity.
CONCLUSION: In patients with chronic renal failure on dialysis, inspiratory muscle training with a fixed load significantly improves respiratory muscle strength, functional capacity, lung function and quality of life. The evidence for these benefits may be influenced by some sources of bias.
REGISTRATION: PROSPERO (CRD 42015029986). [de Medeiros AIC, Fuzari HKB, Rattesa C, Brandão DC, de Melo Marinho PÉ (2017) Inspiratory muscle training improves respiratory muscle strength, functional capacity and quality of life in patients with chronic kidney disease: a systematic review. Journal of Physiotherapy 63: 76-83].
KEYWORDS: Breathing exercises; Chronic renal insufficiency; Haemodialysis; Physical therapy; Respiratory muscle training
PMID: 28433237 DOI: 10.1016/j.jphys.2017.02.016

Background: Respiratory muscle weakness represents one of the potential mechanisms contributing to exertional dyspnea and reduced exercise performance in lung and breast cancer survivors. Purpose/Objective: Pilot study of a respiratory muscle training (RMT) program to improve exercise capacity and quality of life (QOL) and reduce dyspnea in breast and lung cancer survivors. Methods: Participants performed 3 sets of 15 repetitions against spring-loaded inspiratory and expiratory valves, 3 days per week, for 4 weeks, with weekly increases in resistance. Maximal expiratory (MEP) and inspiratory pressures (MIP), exercise tests (o 2peak, submaximal cycling endurance at 70% of peak, and Six-Minute Walk Test [6MWT]) along with questionnaires (Baseline Dyspnea Index and SF-36 [36-Item Short Form Health Survey]) were completed pre- and post-RMT. Design: Single-arm pilot study. Setting: University research and academic medical center. Patients: Lung and breast cancer survivors with the presence of mild-to-moderate dyspnea symptoms not attributed to cardiopulmonary disease. Results: Post-RMT, MIP and MEP increased 29% ± 21% and 34% ± 32%, respectively (P <.001). Submaximal endurance time (16.9 ± 7.4 minutes vs 31.4 ± 7.7 minutes, P =.001), the distance covered in the 6MWT (427 ± 84 m vs 471 ± 95 m, P =.005), dyspnea index (6.4 ± 1.0 vs 7.6 ± 1.3, P =.02), and QOL (total 85.3 ± 9.4 vs 97.8 ± 12.7, P =.014) were all significantly improved post-RMT. Limitations: Limited sample size and short duration of follow-up. Conclusions: These preliminary results support the continued investigation of a respiratory muscle-training program to improve respiratory muscle strength, exercise performance, and QOL, as well as to decrease dyspnea symptoms among cancer survivors.
DOI: 10.1097/01.REO.0000000000000064

[Purpose] To investigate the effects of inspiratory muscle training on respiratory capacity and walking ability in subacute stroke patients.
[Subjects and Methods] The subjects were randomly assigned to an experimental group (n=6) or a control group (n=6). Patients in the experimental group received inspiratory muscle training for 30 minutes (six sets of five-minutes) and traditional physical therapy once a day, five days a week, for four weeks. The control group received aerobic exercise for 30 minutes and traditional physical therapy for 30 minutes a day, five days a week, for four weeks. [Results] After the intervention, both groups showed significant improvements in the forced vital capacity, forced expiratory volume in one second, 10-meter walking test, and six-minute walking test over the baseline results. There were significant between-group differences for the forced vital capacity, forced expiratory volume in one second, and six-minute walking test. No statistically significant differences were observed for measures of saturation pulse oximetry oxygen and 10-meter walking test between the groups. [Conclusion] These findings gave some indications that inspiratory muscle training may benefit in patients with subacute stroke, and it is feasible to be included in rehabilitation program with this population.
KEYWORDS: Inspiratory muscle training; Respiratory function; Walking
PMID: 28265169 PMCID: PMC5333000 DOI: 10.1589/jpts.29.336