Effect of Blood Flow Restriction Resistance Exercises in COPDAE In-patient Rehabilitation

Not Applicable

Completed

Conditions: Chronic Obstructive Pulmonary Disease
Acute Exacerbation of COPD

Interventions: Device: Blood flow restriction resistance exercise

Registration Number: NCT04448236

Lead Sponsor: Hospital Authority, Hong Kong

Brief Summary: This is a randomised controlled trial of the blood flow restriction resistance exercise (BFR-RE) for early rehabilitation of chronic obstructive pulmonary disease acute exacerbation (COPDAE) in the Haven of Hope Hospital.

BFR-RE was invented by Dr. Yoshiaki Sato in Japan 40 years ago. This exercise was newly introduced to the Physiotherapy Department of Haven of Hope Hospital in March, 2020 and not a routine common training in Hospital Authority. However, currently the "BFR-device" is in its 3rd generation. Under the guidance of a certified physiotherapist, a "low load intensity" can be used for resistance training to build up muscle mass and strength by applying the device over the thigh to partially limit the blood flow to the distal limb.

BFR-RE is well studied in athletes, elderlies and patients for rehabilitation after orthopaedics surgeries. A large amount of literature reveals BFR-RE with "low load intensity" shows comparable increase of muscle mass as "high load intensity" resistance training and more increase of muscle strength than those only undergoing "low load intensity" resistance training.

The objective of this study is to investigate the additional effects of 2-week BFR-RE in patients with COPDAE on top of the conventional in-patient rehabilitation training. The primary outcome is effect on localized muscle strength. The secondary outcomes include mobility function, systemic muscle strength as reflected by handgrip strength(HGS), health related quality of life, unplanned readmission to acute hospital rate within 1 month for COPDAE.

Detailed Description: Chronic obstructive pulmonary disease (COPD) is a prevalent disease around the world particularly in developed countries. COPD often has frequent admissions for acute exacerbation which increase the risks of mortality. Muscular dysfunction is one of extra-pulmonary morbidity of COPD.

Reduced muscle strength is associated with increased mortality in moderate to severe COPD. However, at least 70% of 1-repetition maximum (1-RM) of weight is needed to achieve muscle growth in resistance training. This might not be feasible particularly to the patients admitted for COPD acute exacerbation (COPDAE).

Blood flow restriction resistance training (BFR-RE), Kaatsu training, was developed by Dr. Yoshiaki Sato more than 40 years ago. The basic physiological mechanism of BFR-RE to increase muscle mass and strength is by metabolite accumulation, e.g. lactate. The metabolites lead to increase of serum growth hormone (GH) which promotes the collagen synthesis for tissue repair and recovery. The surge of GH leads to release of insulin-like growth factor (IGF-1) which is a protein related to muscle growth. IGF-1 contributes the muscle gain, which is a muscular anabolic process, by enhancing satellite cell proliferation.

Concerning growth of muscle mass, BFR-RE leads to a comparable increase when compared to high load resistance exercise (HL-RE). However, concerning increase of muscle strength, BFR-RE is less effective in gain than that in HL- RE but more effective than that in low load resistance exercise (LL-RE) alone. Therefore, BFR-RE can be considered when HL- RE is not advisable. (e.g. frail elderly, post-operative rehabilitation, etc.) BFR-RE is well studied among healthy adult, elderly and musculoskeletal rehabilitation patients, but not in COPDAE patients.

Standardized isotonic knee extension resistance training on alternate day with a load of 15-30% of 1-Repetition Maximum (1-RM) with "BFR-device" will be compared with the control arm having same set of exercise training without the device in COPDAE patient during 2-week of inpatient stay. Referred to previous study with 30% drop out rate estimation, 24 patients for each arm will be needed. Study period will be set to be 9 months or until expected recruitment achieved.

Though there no adverse risk responses were reported in published randomized controlled trials in clinical populations in the literature, there are some expected transient perceptual type responses, e.g. dizziness, limb numbness, perceived exertion, delayed onset muscle soreness. There are no significant risks of complications if BFR-RE is prescribed by certified trainers who have knowledge of appropriate protocols and contraindications to the use of occlusive stimuli.

The effect on muscle strength in COPDAE inpatient, which is not well studied in the literatures, will be the primary outcome of this study. The effect on mobility functions, systemic muscle strength, health related quality of life, unplanned readmission rate within 1 month of discharge for COPDAE, acceptability and feasibility of the BFR-RE will be evaluated as secondary outcomes.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 53

Inclusion Criteria

COPD acute exacerbation (COPDAE) as the primary diagnosis for hospitalization or transfer to pulmonary wards of the Haven of Hope Hospital
Able to walk under supervision
Understand instruction in Cantonese and can give informed consent.

Exclusion Criteria

Concomitant acute cardiac event
Severe hypertension (BP > 180/100)
History of venous thromboembolism
History of peripheral vascular disease
Absence of posterior tibial or dorsalis pedal pulse
History of revascularization of the extremity
History of lymphectomies
Extremities with dialysis access
Vascular grafting
Current extremity infection
Active malignancy
Open fracture / soft tissue injuries
Amputation to the lower extremity
Expected hospitalization less than 2 weeks on admission
Medications known to increase clotting risks

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
BFR-RE intervention group	Blood flow restriction resistance exercise	The participants will have the standardised 2 week resistance training with "BFR-device" with details as follows: * Cuff size: medium * Restriction time: 5- 10 mins (stop after finishing 4 sets of training or terminating by Physiotherapists) * Applied location: alternate quadriceps in consecutive day * Applied pressure: 80% limb occlusion pressure (LOP)

Primary Outcome Measures

Name	Time	Method
Change of Maximal Voluntary Isometric Contraction (MVIC) of Knee Extension of the Dominant Leg in 3 Weeks	baseline and 3 weeks (after 10-12 sessions of training)	To measure the change of the force-producing capabilities of a muscle group objectively during its isometric contraction condition which means muscle group under contraction with a constant velocity of joint motion and muscle length. Computer dynamometer will be used to measure the MVIC of the isometric knee extension of the dominant leg.

Secondary Outcome Measures

Name	Time	Method
Change of Hand Grip Strength in 3 Weeks	baseline and 3 weeks (after 10-12 sessions of training)	a non-invasive marker of systemic skeletal muscle strength and function, is assessed by handheld grip dynamometer of dominant hand
Acceptability of Blood Flow Restriction Resistance Exercise	Acceptance scale will be assessed immediately after the program after 3 (after 10-12 sessions of training)	Measure the patient's acceptance by a 5-point categorical scale after the whole program. 1=very dislike, 2=dislike,3=no comment, 4= like, 5=very like Lowest score=1 Highest score=5(Higher score means better acceptance)
Change of Scores of Short Physical Performance Battery (SPPB) in 3 Weeks	baseline and 3 weeks (after 10-12 sessions of training)	SPPB is the sum of the points from the following 3 measures, high the point, better performance * Time needed to walk 4m distance: less than 4.82s=4 points, 4.82-6.2s=3 points, 6.21-8.7s=2 points, \>8.7s=1 point; if unable to do the walk=0 point * Balance test: can hold side by side stand 10s= 1 point; semi-tandem stand 10s=1 point; tandem stand 10s=2 point; tandem stand 3-9.99s=1 point; if unable to do the stand=0 point * Repeated chair stands test:; Participant unable to complete 5 chair stands or completes stands in \>60s =0 point; If chair stand time is 16.70s or more= 1 point; If chair stand time is 13.70 to 16.69s = 2 points; If chair stand time is 11.20 to 13.69s=3 points; If chair stand time is 11.19s or less= 4 points Minimum score=0 Maximum score=12(best performance)
Change of Health Related Quality of Life in 3 Weeks	baseline and 3 weeks (after 10-12 sessions of training)	Self-administered Chinese version of Chronic obstructive pulmonary disease(COPD) assessment test (CAT) It contains 8 questions and 6 points each (0 to 5). Higher score means worse health status. The Minimal clinical important difference of CAT score was 2 to 3. Minimum score=0 Maximum score=40 (worst health status)
6-minute Walk Test Distance Gain	baseline and 3 weeks (after 10-12 sessions of training)	the distance can achieved in 6-minute walk test
Average Pain Score of Each Training	pain score before, immediate and 5-minute post exercise;	Visual analog scale (0-10) for before, immediate and 5-minute post exercise. least pain=0 ; most severe pain=10
Reasons of Drop-out of Blood Flow Restriction Resistance Exercise	baseline to 3 weeks (after 10-12 sessions of training)	Examination the reasons of drop-out in those discontinuing the training
Feasibility of BFR Exercise	baseline and 3 weeks (after 10-12 sessions of training)	Examination of drop-out rate
Unplanned Readmission Rate on 1 Month Post Discharge	1 month after the discharge of patients in the study	Unplanned readmission rate within 1 month of discharge for Chronic Obstructive Pulmonary Disease Acute Exacerbation (COPDAE)