The effects of intravenous lidocaine administration on the minimum alveolar concentration of isoflurane in cats

Research output: Contribution to journalArticlepeer-review

96 Scopus citations

Abstract

Lidocaine decreases the minimum alveolar concentration (MAC) of inhaled anesthetics and has been used clinically to reduce the requirements for other anesthetic drugs. In this study we examined the effects of lidocaine on isoflurane MAC in cats. Six cats were studied. In Experiment 1, the MAC of isoflurane was determined. An IV bolus of lidocaine 2 mg/kg was then administrated and venous plasma lidocaine concentrations were measured to determine pharmacokinetic values. In Experiment 2, lidocaine was administered to achieve target plasma concentrations between 1 and 11 μg/mL and the MAC of isoflurane was determined at each lidocaine plasma concentration. Actual lidocaine plasma concentrations were 1.06 ± 0.12, 2.83 ± 0.39, 4.93 ± 0.64, 6.86 ± 0.97, 8.86 ± 2.10, and 9.84 ± 1.34 μg/mL for the target concentrations of 1, 3, 5, 7, 9, and 11 μg/mL, respectively. The MAC of isoflurane in this study was 2.21% ± 0.17%, 2.14% ± 0.14%, 1.88% ± 0.18%, 1.66% ± 0.16%, 1.47% ± 0.13%, 1.33% ± 0.23%, and 1.06% ± 0.19% at lidocaine target plasma concentrations of 0, 1, 3, 5, 7, 9, and 11 μg/mL, respectively. Lidocaine, at target plasma concentrations of 1, 3, 5, 7, 9, and 11 μg/mL, linearly decreased isoflurane MAC by -6% to 6%, 7% to 28%, 19% to 35%, 28% to 45%, 29% to 53%, and 44% to 59%, respectively. We conclude that lidocaine decreases the MAC of isoflurane.

Original languageEnglish (US)
Pages (from-to)97-101
Number of pages5
JournalAnesthesia and Analgesia
Volume100
Issue number1
DOIs
StatePublished - Jan 2005

ASJC Scopus subject areas

  • Anesthesiology and Pain Medicine

Fingerprint

Dive into the research topics of 'The effects of intravenous lidocaine administration on the minimum alveolar concentration of isoflurane in cats'. Together they form a unique fingerprint.

Cite this