99dsButterwick681

Dermatologic Surgery

1999 Abstract

9909-681 Butterwick

Butterwick KJ, Goldman MP, Sriprachya-Anunt S.
Lidocaine levels during the first two hours of infiltration of dilute anesthetic
solution for tumescent liposuction: rapid versus slow delivery. Dermatol Surg. 1999 Sep;25(9):
681-5. PMID: 10491056

Dermatology Associates of San Diego County, La Jolla, CA, USA.

BACKGROUND: Tumescent anesthesia for liposuction with dilute lidocaine has been
well documented to result in peak serum levels 4-14 hours after infiltration.
Pharmacokinetic studies have shown that the rate of lidocaine absorption is
related not only to dilution, but also to the speed of subcutaneous
infiltration. Early studies with a more concentrated solution of lidocaine
(1.0%) have shown that with rapid infusion, peak plasma levels may occur within
30 minutes. OBJECTIVE: To determine whether rapid absorption of lidocaine may
occur during infusion of tumescent solution by varying the rate of infusion of
dilute lidocaine solution (0.05% or 0.1%) and observing serum levels of
lidocaine within the first 2 hours of the procedure. METHODS: Eighteen patients
participated in this study and were infused with a standard liposuction
tumescent formula consisting of lidocaine either 0.05% or 0.1%. The rates of
infusion of tumescent anesthesia ranged from 27.1 mg/min up to 200 mg/min
infused over a period of 5 minutes to 2 hours. Total lidocaine infused ranged
from 7.4 to 57.7 mg/kg. Serum levels of lidocaine were taken every 15 minutes
during the first hour of the procedure and repeated at 2 hours. RESULTS: In all
18 patients, lidocaine levels remained significantly below the toxic range and
were always less than 2.0 microgram/ml. In 11 patients, lidocaine levels at all
time intervals were less than 0.5 microgram/ml. In seven patients, the lidocaine
levels ranged from 0.6 to 1.9 microgram/ml at varying intervals. There was no
correlation between the maximum dose of lidocaine (mg/kg) or rate of lidocaine
delivered (mg/ml) with plasma levels of lidocaine. CONCLUSION: Despite
variability, the serum levels of lidocaine remained well within safety limits
during infusion of tumescent solution and the first hours of the procedure when
infused in rates up to 200 mg/min with spinal needles and/or small diameter
multiholed infusion cannulas.