Signal Extraction Technology in Aviation Medicine: Perfusion-Independent Determination of Peripheral Oxygen Saturation

DOI: 10.36210/BerMedJ/epub102016

Abstract

During air rescue, the technical limitations of conventional pulse oximetry for cases of centralised circulation and shock are amplified due to additional vibration and hypobaric conditions. The current study of 50 patients evaluated different methods of peripheral oxygen saturation (SpO₂) measurement at an average altitude of 2200 feet. Signal extraction technology (SET) measured markedly higher SpO₂ values compared to conventional methods (97% vs. 76%). The SET measurements also took considerably less time (30 vs. 90 seconds), regardless of perfusion status. In 20% of the patients, conventional pulse oximetry yielded no usable measurement.SET oximetry also allows calculation of the perfusion index (PI). In our data, PI values correlated with blood pressure (r=-0.4) and the shock index (r=0.82). In conclusion, the SET Rad5 Oxymeter gives a more reliable measurement than conventional pulse oximetry in cases of patient movement, vibration, decreased perfusion, and shock.