title: Real-time monitoring of endogenous lipid peroxidation by exhaled ethylene in patients undergoing cardiac surgery.
abstract: Pulmonary and systemic organ injury produced by oxidative stress including lipid peroxidation is a fundamental tenet of ischemia-reperfusion injury, inflammatory response to cardiac surgery, and cardiopulmonary bypass (CPB) but is not routinely measured in a surgically relevant time frame. To initiate a paradigm shift toward noninvasive and real-time monitoring of endogenous lipid peroxidation, we have explored pulmonary excretion and dynamism of exhaled breath ethylene during cardiac surgery to test the hypothesis that surgical technique and ischemia-reperfusion triggers lipid peroxidation. We have employed laser photoacoustic spectroscopy to measure real-time trace concentrations of ethylene from the patient breath and from the CPB machine. Patients undergoing aortic or mitral valve surgery-requiring CPB (n = 15) or off-pump coronary artery bypass surgery (OPCAB) (n = 7) were studied. Skin and tissue incision by diathermy caused striking (> 30-fold) increases in exhaled ethylene resulting in elevated levels until CPB. Gaseous ethylene in the CPB circuit was raised upon the establishment of CPB (> 10-fold) and decreased over time. Reperfusion of myocardium and lungs did not appear to enhance ethylene levels significantly. During OPCAB surgery, we have observed increased ethylene in 16 of 30 documented reperfusion events associated with coronary and aortic anastomoses. Therefore, novel real-time monitoring of endogenous lipid peroxidation in the intraoperative setting provides unparalleled detail of endogenous and surgery-triggered production of ethylene. Diathermy and unprotected regional myocardial ischemia and reperfusion are the most significant contributors to increased ethylene.
authors.affiliation: Department of Molecular and Laser Physics, Institute of Molecules and Materials, Radboud University, Nijmegen, the Netherlands;
authors.forename: Simona M
authors.initials: SM
authors.lastname: Cristescu
authors.affiliation: Department of Anaesthesia, Royal Brompton and Harefield NHS Foundation Trust, Harefield, UK; Section of Anaesthesia, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, UK;
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kiss
authors.affiliation: Sensor Sense B.V., Nijmegen, The Netherlands;
authors.forename: Sacco te Lintel
authors.initials: St
authors.lastname: Hekkert
authors.affiliation: Department of Cardiology, Royal Brompton and Harefield NHS Foundation Trust, Harefield, UK;
authors.forename: Miles
authors.initials: M
authors.lastname: Dalby
authors.affiliation: Department of Molecular and Laser Physics, Institute of Molecules and Materials, Radboud University, Nijmegen, the Netherlands;
authors.forename: Frans J M
authors.initials: FJ
authors.lastname: Harren
authors.affiliation: Department of Environmental Health Sciences, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland; and.
authors.forename: Terence H
authors.initials: TH
authors.lastname: Risby
authors.affiliation: Department of Anaesthesia, Royal Brompton and Harefield NHS Foundation Trust, Harefield, UK; Section of Anaesthesia, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, UK; Centre of Anaesthesia and Intensive Care, Semmelweis University, Budapest, Hungary n.marczin@imperial.ac.uk.
authors.forename: Nandor
authors.initials: N
authors.lastname: Marczin
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001944:Breath Tests; D058385:Cardiac Valve Annuloplasty; D002315:Cardiopulmonary Bypass; D005030:Ethylenes / Q000378:metabolism*; D045853:Exhalation; D005260:Female; D006349:Heart Valve Diseases / Q000378:metabolism / Q000601:surgery; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D016343:Monitoring, Intraoperative / Q000379:methods*; D018384:Oxidative Stress
chemical_list: D005030:Ethylenes; C036216:ethylene
keywords: cardiopulmonary bypass; ischemia-reperfusion injury; off-pump coronary artery bypass grafting; oxidative stress