The Tumescent Technique: The Effect of High Tissue Pressure and Dilute Epinephrine on Absorption of Lidocaine

Abstract

Injection of lidocaine into the subcutaneous tissues by the tumescent technique results in a delayed absorption of the local anesthetic and has allowed clinicians to exceed the maximum recommended dose of lidocaine without reported complications. However, little knowledge exists about the mechanisms that permit such high doses of lidocaine to be used safely with this technique. The presence of low concentration epinephrine and the increased tissue pressure resulting from the tumescent injection have both been implicated as important factors, but neither has been studied in patients whose results were not altered by the variability of the suction procedure. The purpose of this work was to determine the effect of tissue pressure during tumescent injection and presence of low concentration epinephrine on the absorption of lidocaine from subcutaneous tissues in human volunteers. Twenty healthy female human volunteers were randomized into four study groups. After body fat measurements, all subjects received an injection of 7 mg/kg of lidocaine into the subcutaneous tissues of both lateral thighs. The injected solution consisted of 0.1% lidocaine and 12.5 meq/liter sodium bicarbonate in normal saline with or without 1:1,000,000 epinephrine. Tissue pressure was recorded during injection using a specially designed double-barreled needle. The time required for injection was also recorded. Subjects in group 1 received lidocaine with epinephrine injected by a high-pressure technique. Group 2 subjects received lidocaine with epinephrine injected by a low-pressure technique. Group 3 subjects received lidocaine without epinephrine injected under high pressure. Group 4 subjects received lidocaine without epinephrine injected under low pressure. Following injection, sequential blood samples were drawn over a 14-hour period, and plasma lidocaine concentrations were determined by gas chromatography. No suction lipectomy was performed. Maximum tissue pressure during injection was 339 +/- 63 mmHg and 27 +/- 9 mmHg using high- and low-pressure techniques, respectively. Addition of 1:1,000,000 epinephrine, regardless of the pressure of injected fluid, significantly delayed the time to peak plasma concentration by over 7 hours. There was no significant difference in the peak plasma concentration of lidocaine among the four groups. Peak plasma concentrations greater than 1 mcg/ml were seen in 11 subjects. Epinephrine (1:1,000,000) significantly delays the absorption of lidocaine administered by the tumescent technique. High pressure generated in the subcutaneous tissues during injection of the solution does not affect lidocaine absorption. The delay in absorption may allow time for some lidocaine to be removed from the tissues by suction lipectomy. In addition, the slow rise to peak lidocaine concentration in the epinephrine groups may allow the development of systemic tolerance to high lidocaine plasma levels.

Liposuction: Anaesthesia challenges

“…These factors are subcutaneous fat, which has a relatively low volume of blood flow, dilute epinephrine, which produces a prolonged and profound degree of vasoconstriction and lignocaine itself, which is lipophilic and readily sequestered in fat cells. [2223]…”

Tumescent Liposuction Report Performance Measurement Initiative: National Survey Results

“…Further, blood loss cannot be calculated from blood in the aspirate, 24 and the concentration of epinephrine affects lidocaine absorption. 25 Other issues of controversy associated with liposuction include infusion rates and use of premedication, 26 the efficacy of external ultrasound-assisted liposuction, internal ultrasonic-assisted liposuction or external ultrasound after liposuction, [27][28][29][30] and use of postoperative garments/length of postoperative compression. 31,32…”

Electrochemotherapy Under Tumescent Local Anesthesia for the Treatment of Cutaneous Metastases

“…Vasoconstrictor additives increase the duration of action of the anesthetic agents and decrease systemic toxicity. 19 Adrenaline may also act synergistically with the vascular effects of electroporation. Local vasoconstriction delays the systemic dissemination of the intratumoral drug.…”