Intraoperative awareness as an example of the influence of cardiac output on anesthetic dosing: case report
A case of intraoperative awareness during ablation of pulmonary veins-one of the most widely used techniques in interventional cardiology-is discussed. An infusion of isoproterenol was administered following the ablation of ectopic foci. A few seconds after the infusion the patient experienced increased heart rate and intraoperative awareness manifested as an abrupt patient movement and bispectral index elevation. This has been described in similar procedures, following the administration of isoproterenol. In our opinion, the isoproterenol infusion caused the increased heart rate and subsequent abrupt rise in cardiac output. As an inversely proportional relationship between the propofol concentrations and cardiac output has been described, we believe that this rise in cardiac output could have favored the decline in the concentrations of propofol, leading to an intraoperative awareness episode.
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