Impaired breathing during relaxed sleep results in changed pulse rate, oxygen saturation and RE. Central respiratory disorders results in decreased RE, while Obstructive problems gives increased RE. Diagnosis is obtained from measurements of parameters describing these different modalities.
SRBD represent a relatively new, large disease entity. Diagnostic criterias are established by the American Academy of Sleep Medicine (AASM 2007). This leads to new demands for recording, analysis and diagnosis. Revised in 2011 & 2014.
The incidence for SRBD in the adult population is 15 – 20%, while OSA is found in 3–5%. The incidence for SRBD in children is 12 - 14 %, while OSA is found in 1 – 2 %.
SRBD is initiated by muscle relaxation when patients fall asleep. When the muscles in the upper airways relax, the lumen becomes narrower and the patient starts to snore. Such a narrowing causes difficulties in breathing which demands more working effort of the respiratory muscle (Respiratory Effort = RE). If the narrowing continues, the oxygen saturation will drop and the carbon dioxide tension increase. This demand for increased activity of the respiratory muscles will eventually cause the brain to trigger awakenings (arousals). This is called Respiratory Effort Related Arousals = RERA. Due to this arousal, the muscles in the airway increase the tone and open up the lumen. The patient can then breathe again. When the patient falls to sleep, the muscles in the upper airway relax and the cycle starts again.
The unique ApneaGraph Spiro provides clear market leading
signal displays and information on the following:
- Differentiation between central and obstructive apneas
- Quantitative respiratory effort
- Severity of SRBD
- Location of obstruction
- Snoring : sound, duration and location of obstruction