Capnometry is a way of analyzing how you are breathing with respect to fulfilling the chemical requirements of ventilating your body. Disordered breathing is common in clients who experience chronic pain or anxiety. Often the problem begins with a traumatic event from which recovery was delayed. Breathing habits change during this time and the altered rate, rhythm, depth and pattern of respiration can lead to a state called hypocapnia.
Hypocapnia occurs when too much CO2 is excreted by breathing inappropriately (too fast and/or too deeply); a CO2 deficit quickly develops resulting in alkalosis where the pH of the blood and other fluids is too high. The effects can be insidious and dramatic and can cause a wide variety of emotional, perceptual, cognitive, attention, behavioral, and physical changes in performance and health.
Hypocapnia is often difficult to recognize with the standard clinical orthopaedic tests of observation and palpation. The gold standard for measuring CO2 levels is via arterial blood gases and this requires an invasive technique; not suitable for the clinical orthopaedic setting. However, values can be obtained using capnometry which measures CO2 concentration in exhaled air.
Capnotrainer
(Better Physiology Limited)
Clinical Observations
Clinically, it has been observed that overbreathing is a factor in those who:
- brace their chest wall excessively using high load muscle strategies during low load tasks,
- are unable to maintain the effects of manual treatment and exercise,
- have flared with manual treatment,
- have a type 'A' or 'go for it' personality,
- have substantial pain behaviour,
- or have an anxious personality.
All physiotherapists at Diane Lee & Associates - Consultants in Physiotherapy are trained to use capnometry when appropriate for both assessment and treatment of disordered breathing. Further information on hypocapnia and capnometry can be found at www.bp.edu.
