Obstructive sleep apnea - reliable diagnosis without thermistors

Obstructive Sleep Apnea: Health Risks

Sleep-related breathing disorders increase the risk of various diseases, such as high blood pressure, coronary heart disease, stroke, heart failure, type 2 diabetes, and depression.
85% of sleep-related breathing disorders are caused by obstructive sleep apnea (OSA). OSA results in a total or partial collapse of the upper airways during sleep, typically triggering an arousal response in the patient.
Those affected often suffer from daytime fatigue and lack of concentration. In Germany alone, approximately 2-4% of the population exhibits signs of obstructive sleep apnea syndrome (OSAS). In the USA, it is estimated that 9% of women and 25% of middle-aged men are affected.
If left untreated, OSAS can lead to serious consequences for the cardiovascular system and a reduced quality of life.

Diagnosis of OSA

Sleep-related breathing disorders are characterized by a blockage of the upper airways, which can lead to a reduction in airflow (hypopnea) or even complete cessation of breathing (apnea).
The Apnea-Hypopnea Index (AHI) refers to the average number of apnea and hypopnea episodes per hour of sleep. It provides an indication of the severity of a sleep-related breathing disorder and is also used to monitor treatment success.

According to the AASM guidelines (version 2.4), the diagnosis of OSA should be performed using a thermistor (for detecting apneas) in combination with an additional nasal cannula (for detecting hypopneas).

CNSAC MedShop GmbH, in cooperation with various sleep laboratories in Germany, Denmark, and Finland, has developed a combined nasal/mouth cannula that can reliably detect both apneas and hypopneas by linearizing the airflow.
In a currently ongoing study, the accuracy of this method is being compared with the AASM-recommended combination of thermistor and nasal cannula.
Preliminary results(71 of the planned 200 patients) clearly demonstrate that the CNSAC nasal/mouth cannula is highly sensitive and enables reliable diagnosis of obstructive sleep apnea.

AHI Classification and Performance of the CNSAC Nasal/Mouth Cannula

Table 1: Sensitivity and specificity of the newly developed nasal/mouth cannula for diagnosing OSA

Nasal/Mouth Cannula by CNSAC MedShop GmbH

This innovative nasal/mouth cannula allows for the detection of obstructive sleep apnea in accordance with AASM diagnostic guidelines, without the need for a thermistor.
In addition to improved patient comfort and easier practical use, the new product also offers reduced ongoing costs in sleep diagnostics.

References

• SOMNOmedics internal study, conducted in April 2016

• Küchler et al, Eur Respir J 2017; DOI: 10.1183/1393003

• Marshall et al, Sleep, 2008

• Matthys H, Seeger W: Clinical Pneumology. Springer Publishing House, 2008