Prognostic Value of Exhaled Isoprene Levels for Morbidity and Functional Outcome in Cardiosurgical Patients

The perioperative preservation of functionality and quality of life plays an increasingly important role in older physically limited and frail patients undergoing cardiac surgery. Hereby, impairments of the skeletal muscle system integrity often contributes to a reduced physical performance. Early identification of these high-risk patients could help to initiate appropriate preventive and therapeutic measures. Volatile organic compounds (VOC) represent a non-invasive and real-time measurable approach for recording physiological and pathophysiological processes. Isoprene (2-methyl-1,3-butadiene) is one of the most abundantly exhaled VOCs and has recently been shown to originate from skeletal muscle metabolism. However, the prognostic value of isoprene as a volatile biomarker for skeletal muscle integrity, physical performance and functional outcome in patients undergoing cardiac surgery has not been evaluated before.