More Air - Better Performance - Faster Recovery (IMT)

"More Air - Better Performance - Faster Recovery": Study Protocol for a Randomised Controlled Trial of the Effect of Inspiratory Muscle Training for Adults Post-stroke

The objective of this study is to investigate i) the effect of 3 weeks IMT to adults post-stroke to maximal inspiratory pressure (MIP) and ii) the effects of 3 weeks IMT to the degree of dependency in activities of daily living, endurance in gait, fatigue, voice volume, phonation endurance, and expiratory function. Methods/Design: Randomised controlled trial (RCT) comparing IMT to conventional neurorehabilitation (usual practise). 80 patients, with reduced maximal inspiration pressure (MIP) hospitalized at a specialized neurorehabilitation hospital in Denmark will be included.

Background: Stroke results in varying disabilities physical, cognitive, emotional and/or social both in short term and long term. Motor impairments are significantly persistent consequences post-stroke among these are decreased respiratory muscle function, decreased ability to expand thorax and postural dysfunction. These deficits influence the patient's ability in daily activities, fatigue, endurance and quality of life. Inspiratory muscle training (IMT) is training to improve the strength and endurance of diaphragm and the external intercostal muscles. The objective of this study is to investigate i) the effect of 3 weeks IMT to adults post-stroke to maximal inspiratory pressure (MIP) and ii) the effects of 3 weeks IMT to the degree of dependency in activities of daily living, endurance in gait, fatigue, voice volume, phonation endurance, and expiratory function. Methods/Design: Randomised controlled trial (RCT) comparing IMT to conventional neurorehabilitation (usual practise). 80 patients, with reduced maximal inspiration pressure (MIP) hospitalized at a specialized neurorehabilitation hospital in Denmark will be included. The intervention group will add-on IMT sessions exercising at 30 % of MIP. Patients in the intervention group perform 2 sessions a day (One session of IMT with IMT threshold flute consists of 2 times 15 inspirations in normal breathing rhythm (5-10 min)), 7 days a week for 3 weeks. Training can be with or without supervision of physiotherapist.

2 x IMT (5-10 min) 2 times a day 7 days a week for 3 weeks with or without supervision Log-book Conventional neurorehabilitation

IMT and conventional neurorehabilitation - treatment as usual. The intervention group will add-on IMT sessions exercising at 30 % of MIP. MIP is measured by instructing the patient to perform five forceful inspirations against an occluded mouthpiece (Power Breath). The best score is multiplied by 0.3 to determine the resistance. IMT is performed with IMT Threshold flute with the calculated resistance. During the measurement with Power Breath the patient sits straight up and uses nose clip. The patient can receive help to hold the Power Breath if necessary. One session of IMT with IMT threshold flute consists of 2 times 15 inspirations in normal breathing rhythm (5-10 min). Patients in the intervention group perform 2 sessions a day (morning and evening), training is performed prior to a meal, 7 days a week for 3 weeks.

Change of MIP assess with the Power Breath. This is an objective measurement to describe the inspiratory capacity. Age specific

Assessed 0-4 days before intervention, 0-4 days after ended intervention assessment and 3 months after ended intervention

Functional Independence Measure (FIM) - both total score ( range from 18 to 126, with higher scores indicating more independence) and motor sub score (max 91)

Assessed 0-4 days before intervention, 0-4 days after ended intervention assessment and 3 months after ended intervention

Assessed 0-4 days before intervention, 0-4 days after ended intervention assessment and 3 months after ended intervention

Assessed 0-4 days before intervention, 0-4 days after ended intervention assessment and 3 months after ended intervention

to measure change of voice volume by recording of an a-sound with the App Voice Analyst and to measure Phonation endurance (how long the a-sound last)

Assessed 0-4 days before intervention, 0-4 days after ended intervention assessment and 3 months after ended intervention

To measure change of Peak expiratory flow (PEF), Forced expiratory volume in 1 second (FEV1), Forced vital capacity (FVC) and FEV1/FVC ratio will be assessed with a peak flow meter (Spirometry device Micro 6300)

Assessed 0-4 days before intervention, 0-4 days after ended intervention assessment and 3 months after ended intervention

Inclusion Criteria: First time brain infarction or brain haemorrhage 0-6 month. Able to give written consent and being cognitive and communicative able to understand and participate in the maximal inspiration pressure test (MIP) Reduced MIP below gender and age specific normal standard Exclusion Criteria: Diagnosis of myocardial infarction within the last 3 months Significant pulmonary disease (severe COPD), saturation below 90 if having COPD for others saturation below 92 Neurological deficits other than stroke Facial palsy that affects proper labial occlusion Dizziness or nausea/vomiting during MIP-testing.

Sorensen SL, Kjeldsen SS, Mortensen SS, Hansen UT, Hansen D, Pedersen AR, Pallesen H. "More air-better performance-faster recovery": study protocol for randomised controlled trial of the effect of post-stroke inspiratory muscle training for adults. Trials. 2021 Aug 28;22(1):575. doi: 10.1186/s13063-021-05551-8.