High-dose lidocaine does not affect defibrillation efficacy: implications for defibrillation mechanism

The relationship between the dose of lidocaine which is reflective of the sodium channel blockade and the defibrillation energy requirement (DER) during cardioversion is investigated using pigs as study subjects. Results reveal that the graphical relationship between lidocaine dose and DER takes the shape of an inverted U where the DER begins to fall at elevated dosages of lidocaine. The implications of these findings on cardioversion are presented.