A comparison of methods of lidocaine administration in patients.

A three-step method for administering lidocaine intravenously was developed and tested in 19 patients. Of all plasma concentrations measured, 70% were within the desired range of 2 to 4 micrograms/ml after the new method of lidocaine administration. Compared with other methods it is superior with respect to percent of time in the therapeutic range. No ventricular arrhythmias were evident, and no toxicities were associated with the new method. Infusions of lidocaine for more than 6 hr were associated with progressive increases in plasma concentrations that were higher (p less than 0.01) at 24 hr than at 6 hr.