Respiratory Muscle Dysfunction

Question 1

Definition

Answer 1

a lack of strength or endurance of the inspiratory or expiratory muscles of ventilation

Question 2

Causes

Answer 2

neuromuscular disease
connective tissue diseases
chronic lung disease
chest wall disorders 
post surgery 
oral corticosteroids 
malnourishment

Question 3

Clinical Significance

Answer 3

Reduced lung volumes 
- unable to generate sufficient VC due to weakness 
Impaired airway clearance 
- unable to generate sufficient VC or PEFR
Resultant impairments 
- decreased exercise tolerance 
- impaired gas exchange 
- dyspnoea
- abnormal breathing pattern

Question 4

Clinical Features

Answer 4

Patient reports breathlessness
- usually when supine
- when standing in water up to chest
- when completing ADLs that require UL function
Symptoms of night time hypoxaemia
- daytime sleepiness
- early morning headaches
- impaired mental function
Muscle strength testing performed in pulmonary labs
Spirometry (Extrapolate strength from volume values)
Paradoxical breathing patterns
elevated hemidiaphragm dome in unilateral diaphragmatic paralysis

Question 5

Physio Intervention

Answer 5

targeting respiratory muscle training
whole body exercise
non-invasive ventilation

Question 6

Targeted Respiratory Muscle Training

Answer 6

via threshold or resistive devices
Freq. 4-5x per week
Int. 30% max inspiratory pressure
Time - 30 mins total each time

Question 7

Whole body exercise

Answer 7

improves respiratory muscle strength and peripheral skeletal muscle efficiency
Freq. - daily/most days
Int. - 3-4/10 on BORG
Type - endurance and strength
Time - 30-60 mins, at least 10mins at a time

Question 8

Non-invasive ventilation

Answer 8

Mainly to allow resp. muscles time to rest

Patients with severe dysfunction