[Efficiency of portable sleep apnea screening instruments].

Diagnosis of a sleep apnoea syndrome in severely snoring patients with diurnal sleepiness is growing in importance in the consulting rooms of general practitioners, internists, ENT specialists and pneumologists. However, time and cost reasons limit the diagnostic procedures conducted by practitioners to outpatient screening. Two different systems are presently available in Germany. The MESAM system (Madaus, Freiburg) records by means of a microphone and various electrodes the oxygen saturation, heart rate, snoring and sleeping position of the patient. The Apnoe-Check System (Medanz, Starnberg) determines the nasal and oral respiratory flow by means of a mask fitted with thermistors. Evaluation is accomplished in the case of MESAM via a conventional personal computer whereas with the Apnoea Check System the apnoeas and their duration can be read off direct from a writer. The cost ratio of these systems is approximately 3:1 (MESAM:Apnoea Check). Wie compared both systems by parallel measurements on 19 female and male patients and controlled the results obtained by measurements with a CO2 infrared absorption spectrometer in our sleep lab. A total of 3201 nocturnal events were recorded via MESAM and 1488 via the Apnoe-Check System. The highest number of apneas was recorded by MESAM in a patient with severe sleep apnea syndrome, namely, 546 apnoeas in one night. The lowest number of apnea events was experienced by a healthy male with 33 apneas in a night. With the Apnoe Check the maximum of nocturnal events was 255, the minimum being 8 events in one patient. In 64.6% of all nocturnal events there was time congruence for both systems.(ABSTRACT TRUNCATED AT 250 WORDS)