Category: Clinical Engineering
Hospital scientists are using sound waves to detect airway changes in patients with severe lung conditions.
Impulse oscillometry (IOS) was introduced at Birmingham's Queen Elizabeth Hospital to tackle problems associated with conditions like chronic obstructive pulmonary disease (COPD) and asthma.
Computer-aided IOS enables clinicians to detect subtle changes in a patients airway function earlier than when using conventional and more expensive techniques.
As the patient breathes through a pneumo-tachograph, a sound wave generated by a loudspeaker is superimposed over their breathing. The patients airflow and sound wave response is transmitted to the apparatus and used to calculate the various components of resistance to breathing.
Currently, this innovative technique has produced excellent results in clinical services both for patients who have received lung transplants and for those with severe airways disease.
The procedure's benefits include:
Objective lung function measurements are routinely used to diagnose and manage asthma, but their utility for young children has not been defined.
In one American study, Bronchodilator responses were measured using impulse oscillometry (IOS) and compared with conventional spirometry to determine the value of lung function measures in 4-year-old asthma-prone children.
The study participants were in the Childhood Asthma Prevention Study (National Institute of Health/National Institute of Allergy and Infectious Diseases) and at risk for asthma. At age 4 years, concurrent asthma was determined by using a previously validated modified American Thoracic Society questionnaire. Children performed IOS and spirometry before and after albuterol administration and underwent skin prick testing to 13 common allergens to assess atopy.
IOS bronchodilator responses are remarkably abnormal in 4-year-old children, who are most likely to have persistent asthma. IOS is a useful diagnostic tool in early asthma development and might be a helpful objective outcome measure of early interventions. (J Allergy Clin Immunol 2003;112:317-22.)
(This functionality will vary with different devices)
Lung Volumes by Nitrogen Washout
Diffusing Capacity, Single Breath
Diffusing Capacity, Intra-breath (NON-BREATH HOLDING)
Compression Free F/V Loops
Inspiratory and Expiratory Pressures
Vmax Encore PFT
Impulse oscillometry provides an effective measure of lung dysfunction...
Impulse Oscillometry System (IOS) as a Method of Early Detection of Lower Airway Obstruction...
Detecting lung diseases with sound waves.