Monitoring of oxidative and metabolic stress during cardiac surgery by means of breath biomarkers: an observational study

Abstract

BackgroundVolatile breath biomarkers provide a non-invasive window to observe physiological and pathological processes in the body. This study was intended to assess the impact of heart surgery with extracorporeal circulation (ECC) onto breath biomarker profiles. Special attention was attributed to oxidative or metabolic stress during surgery and extracorporeal circulation, which can cause organ damage and poor outcome.Methods24 patients undergoing cardiac surgery with extracorporeal circulation were enrolled into this observational study. Alveolar breath samples (10 mL) were taken after induction of anesthesia, after sternotomy, 5 min after end of ECC, and 30, 60, 90, 120 and 150 min after end of surgery. Alveolar gas samples were withdrawn from the circuit under visual control of expired CO2. Inspiratory samples were taken near the ventilator inlet. Volatile substances in breath were preconcentrated by means of solid phase micro extraction, separated by gas chromatography, detected and identified by mass spectrometry.ResultsMean exhaled concentrations of acetone, pentane and isoprene determined in this study were in accordance with results from the literature. Exhaled substance concentrations showed considerable inter-individual variation, and inspired pentane concentrations sometimes had the same order of magnitude than expired values. This is the reason why, concentrations were normalized by the values measured 120 min after surgery. Exhaled acetone concentrations increased slightly after sternotomy and markedly after end of ECC. Exhaled acetone concentrations exhibited positive correlation to serum C-reactive protein concentrations and to serum troponine-T concentrations. Exhaled pentane concentrations increased markedly after sternotomy and dropped below initial values after ECC. Breath pentane concentrations showed correlations with serum creatinine (CK) levels. Patients with an elevated CK-MB (myocardial&brain)/CK ratio had also high concentrations of pentane in exhaled air. Exhaled isoprene concentrations raised significantly after sternotomy and decreased to initial levels at 30 min after end of ECC. Exhaled isoprene concentrations showed a correlation with cardiac output.ConclusionOxidative and metabolic stress during cardiac surgery could be assessed continuously and non-invasively by means of breath analysis. Correlations between breath acetone profiles and clinical conditions underline the potential of breath biomarker monitoring for diagnostics and timely initiation of life saving therapy.

Breath analysis during one-lung ventilation in cancer patients

“…Lung surgery lasted between 1.5 and 5.0 h. Therefore, exhaled acetone concentrations were additionally increased through lipolysis and ketogenesis after prolonged fasting. This phenomenon has already been observed by PABST et al [16] and MIETH et al [17] in patients undergoing cardiac surgery. Hence, acetone represents an interesting metabolic marker but is not a cancer specific substance.…”

Impact of Exhaled Breath Acetone in the Prognosis of Patients with Heart Failure with Reduced Ejection Fraction (HFrEF). One Year of Clinical Follow-up

“…According to the authors’ conclusions “ exhaled breath acetone (EBA) seems to be not only a promising non-invasive diagnostic method of HF , whose accuracy is equivalent to BNP , but also a new biomarker of HF severity , since EBA levels differed significantly as a function of severity of HF (NYHA—New York Heart Association classification)” . [8] Other studies have shown higher levels of acetone in exhaled breath of patients with heart disease[9,10]. However, there is no data on the role of acetone as a prognostic biomarker of HF.…”

Assessment of the exhalation kinetics of volatile cancer biomarkers based on their physicochemical properties

“…Exhaled breath, which may change its chemical signature depending on the physiological or pathophysiological state of disease [12][13][14][15][16][17][18][19][20][21][22][23][24], is considered as one of the most fascinating body fluids/sources. Sampling of breath is non-invasive and can be used for screening, at an intensive care unit (ICU) [25,26], during surgery [27][28][29], or monitoring pre-and post-surgery [30]. Volatile compounds that do not appear normally in exhaled breath can be used for detection of bacterial or fungal infection in the lungs [31][32][33][34][35].…”