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Inspiratory muscle strength in acute asthma
I M Stell1, M I Polkey, P J Rees
1Department of Accident & Emergency Medicine, King's College Hospital, London, UK. ian.stell@bromleyh_tr.sthames.nhs.uk
Chest
|September 14, 2001
Summary
This study found no evidence of inspiratory muscle weakness in patients with acute asthma. Inspiratory pressure measurements were normal, suggesting fatigue is not a primary factor in their breathlessness.
Area of Science:
- Respiratory Medicine
- Pulmonology
- Critical Care
Background:
- Acute asthma can lead to breathlessness and respiratory failure.
- Inspiratory muscle fatigue is a potential contributing factor to these symptoms.
Purpose of the Study:
- To measure the inspiratory pressure-generating capacity in patients with acute asthma.
- To investigate the role of inspiratory muscle fatigue in acute asthma exacerbations.
Main Methods:
- A descriptive study was conducted in the emergency departments of two inner-city hospitals.
- Fifty-one patients with acute asthma and 45 healthy controls were enrolled.
- Sniff nasal inspiratory pressure (SNIP) was used to measure inspiratory capacity.
Main Results:
- Patients with acute asthma showed reduced mean SNIP compared to controls (men: 110 vs 126 cm H2O; women: 80 vs 105 cm H2O).
- Airway obstruction effects on SNIP were assessed, revealing minor reductions in inspiratory pressure-generating capacity.
- Observed reductions were consistent with modest hyperinflation in patients with moderately severe asthma.
Conclusions:
- The study did not find evidence of significant inspiratory muscle weakness or fatigue in patients with moderately severe acute asthma.
- Inspiratory muscle function appears preserved in this patient group presenting to the emergency department.
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