The Apnea-Hypopnea Index (AHI) is still the "gold standard" for the diagnosis of sleep-related breathing disorders. The AHI measures the number of apneas and periods with significantly reduced tidal volume in patients with obstructive and central sleep apnea. Recently, however, attempts have been made to find parameters which widen the perspective of how sleep-related breathing disorders should be analyzed.
With support provided by the Hamburg-based medical technology company Weinmann, a team led by Professor Dr. Jan Hedner and Assistant Professor Ludger Grote (Sahlgrenska University Hospital, Gothen-burg, Sweden) and his team have been working on the development of a new concept, the Autonomic State Indicator Concept (ASIC).
"With this project we would like to optimize the diagnosis of sleep-related breathing disorders and the assessment of the related cardiovascular risk," said Dr. Hedner at a press conference during the European Respiratory Society congress in Stockholm. "We are using the pulse wave amplitude, which can provide us with a multitude of information."
In the future hopefully it will be possible to make greatly differentiated risk assessments and more accurate prognoses with regard to cardiovascular morbidity related to the obstructive sleep-related breathing disorder. This diagnostic method appears to allow for rapid identification of those individuals with high cardiovascular risk and may prove to be especially significant for patients with heart failure and sleep-related breathing dis-orders such as Cheyne-Stokes Breathing because different parameters can be measured more easily and effectively.
"This method takes into consideration that sleep-related breathing disorders are systemic illnesses that should be regarded as such. Given our current approach and the complexity of these disorders, it no longer suffices to simply count the number and record the duration of the apneas," Dr. Hedner said.