Adenosine-induced cardiac arrest and EEG changes in patients with thoracic aorta endovascular repair

Background. We studied haemodynamic and metabolic variables,and cerebral function after cardiac arrest induced by high doseof adenosine in patients undergoing thoracic aorta endovascularrepair. Methods. Arterial blood pressure, blood gas values and EEG wererecorded continuously in 15 patients undergoing anaesthesia(isoflurane) for endovascular thoracic aorta repair. Cardiacarrest was induced by different doses of adenosine (Adrekar®,Sanofi-Synthelabo, Berlin, Germany; 0.4–1.8 mg kg^–1body weight). Serum concentrations of neurone-specific enolase(NSE) were determined before and after stent graft implantation.Neurological function was assessed before and after surgery. Results. After adenosine, the heart beat stopped immediatelyfor 18–58 s in close relation to the adenosine dose. EEGpower was significantly reduced to –57%, but reached normalvalues within 5 min after cardiac arrest. In particular, thefast alpha- and beta-EEG-frequencies sensitively reflected patients'EEG activity during the procedure. No intraoperative increasesin NSE concentrations, and no neurological dysfunctions aftersurgery, were observed. Conclusion. After adenosine-induced cardiac arrest, changesin haemodynamic variables and EEG power spectra reversed completelywithin 1 and 5 min, respectively, without persistent brain dysfunctionafter stent graft implantation.