Applications and examples

Capnographic recording offers two distinct advantages :

1. cooperation-independency : the subject may be resting or even sleeping,
2. non-invasiveness : recording may be performed for several hours.

These two features make it the best method for two kinds of applications :

1. effort-independent bronchospasm measurements (especially in children and non-cooperative adults),
2. continuous asthma monitoring.

"Effort-independent" bronchospasm evaluations

• Normal recording
• Normal recording in a patient unsuited to forced flow spirometry .
• Asthma attacks.
• Child's bronchial provocative test.

Bronchospasm monitoring under various conditions

• Inhalative bronchial challenge using broncho-constrictive agent,
• Inhalative bronchial challenge using broncho-dilatator therapy,
• Nocturnal asthma monitoring,
• Pharmacological study ( duration of action of bronchodilatator therapy).

Method limitations
Reliable capnographic recording has only two requirements : 1) the subject should be relaxed, 2) nasal airways should be permeable (at least on one side!). This excludes tests on very anxious or restless patients as well as on patients with untreated obstructive rhinitis.