title: Simple method for maintaining serum lidocaine levels in the therapeutic range.
abstract: Lidocaine hydrochloride is commonly infused intravenously to prevent ventricular arrhythmias. In some patients, elevations in serum lidocaine levels can cause serious toxic effects. In a group of 19 patients given a constant infusion of lidocaine, we confirmed the observation that serum lidocaine levels rose significantly between four and 24 hours after initiation of therapy. One of these patients manifested a toxic reaction to lidocaine. The lidocaine infusion rate was modified in a second group of 32 patients on the basis of the four-hour serum level. In these patients, after dosage adjustment, the mean lidocaine level did not rise, and all levels remained within the 2- to 4-mg/L therapeutic range at 24 hours. Without dosage adjustment, half of these levels would have fallen outside the desired range. A simple formula can be used to adjust prophylactic lidocaine infusion rates to attain levels that remain therapeutic, yet nontoxic.
mesh_terms: D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000097:blood / Q000188:drug therapy*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007263:Infusions, Parenteral; D007700:Kinetics; D008012:Lidocaine / Q000008:administration & dosage / Q000009:adverse effects / Q000097:blood / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D008012:Lidocaine