Frequent sampling allows detection of short and rapid surges of exhaled ethane during cardiac surgery

Abstract

During cardiopulmonary bypass (CPB), hypoperfusion and reperfusion may cause oxidative stress and lipid peroxidation that generates ethane. The aim of this pilot study was to assess the feasibility of frequent sampling of exhaled ethane during cardiac surgery. After approval of the Research Ethics Committee, 10 patients undergoing combined aortic valve and coronary artery bypass surgery were enrolled. Breath samples were drawn in the perioperative period and analyzed by a rapid, sensitive and validated gas-chromatographic method. Increased exhaled ethane was regularly seen following sternotomy, after the start of CPB and after aortic clamp removal, whereas no change was seen after termination of bypass. In one patient, the maximum increase in exhaled ethane was 30-fold. Peak durations lasted only 2-4 min. This study demonstrates that frequent sampling of breath ethane is feasible in a clinical setting, allowing detection of rapid ethane surges of short duration.

Real-time monitoring of endogenous lipid peroxidation by exhaled ethylene in patients undergoing cardiac surgery

“…EXHALED ETHYLENE IN CARDIAC SURGERY lipid peroxidation (2,19,26). Firstly, our experiments reveal previously unrecognized details and magnitude of early hydrocarbon release associated with diathermy and skin incision.…”

“…On the basis of short-chain hydrocarbon production during decomposition of omega fatty acids, the pulmonary excretion of volatile gases ethane and pentane have been considered noninvasive exhaled breath biomarkers of total body and myocardial lipid peroxidation. The milestone study of Andreoni et al (2) and subsequent studies (14,19,26) utilized discrete breath collections and laboratory analysis and provided insights into these breath biomarkers. However, there are significant inherent limitations of such methodology and significant controversy remains regarding the triggers, timing, and relevance of ethane kinetics.…”

“…Parallel to these biomarker studies, pulmonary excretion and analysis of volatile organic compounds in exhaled breath have also been considered. Interestingly, exhaled breath hydrocarbons have emerged as gaseous footprints of in vivo lipid peroxidation, but studies have been limited to discrete sampling and offline analysis in a specialized laboratory setting with results unavailable in a surgically relevant time frame (2,19,23,26).…”

Lipid peroxidation in cardiac surgery: towards consensus on biomonitoring, diagnostic tools and therapeutic implementation

“…However, the authors demonstrated in a swine skin incision model that the increase of the ethane in the exhaled breath is related to the use of the electrocautery [14]. Same increase of the ethane soon after the diathermy was reported later by Stenseth et al [15].…”

“…There are two principal analytical substrates that have been used to monitor oxidative stress and these are fluid phase samples including various samples obtained from the circulation or gas phase samples from the airway compartment as breath condensate. Analysis of volatile molecules in breath, including ethylene, pentane and ethane, have also been reported at various stages during cardiac surgery [13][14][15][16].…”