The effect of adjuvant epinephrine concentration on the vasoactivity of the local anesthetics bupivacaine and levobupivacaine in human skin

TY - JOUR

T1 - The effect of adjuvant epinephrine concentration on the vasoactivity of the local anesthetics bupivacaine and levobupivacaine in human skin

AU - Newton, David J.

AU - McLeod, Graeme A.

AU - Khan, Faisel

AU - Belch, Jill J. F.

PY - 2004

Y1 - 2004

N2 - The recommended optimal concentration of adjuvant epinephrine for use with local infiltration anesthesia is usually 5 µg/mL. However, a lower dose might be as effective at prolonging the anesthetic effects, while limiting the risk of hazards associated with unintentional intravascular injection. The aim of our study was to determine the lowest effective vasoconstrictor concentration of epinephrine in human skin for a range of doses of bupivacaine and its less-vasodilatory S(-) isomer, levobupivacaine. We injected combinations of 0.125%, 0.25%, and 0.75% bupivacaine and levobupivacaine with 1.25, 2.5, and 5 µg/mL epinephrine into the forearm skin of 10 healthy volunteers and measured the resulting blood flow changes over 1 hour using laser Doppler imaging. All 3 concentrations of epinephrine produced marked vasoconstriction, both alone and in combination with all 3 doses of the anesthetics (P < .001 in all cases). There was almost no difference in effect between the 3 epinephrine concentrations. We conclude that 1.25 µg/mL epinephrine produces a comparable vasoconstrictor effect in human skin to that of higher concentrations when coinjected with clinical doses of bupivacaine and levobupivacaine and may be equally effective for infiltration anesthesia.

AB - The recommended optimal concentration of adjuvant epinephrine for use with local infiltration anesthesia is usually 5 µg/mL. However, a lower dose might be as effective at prolonging the anesthetic effects, while limiting the risk of hazards associated with unintentional intravascular injection. The aim of our study was to determine the lowest effective vasoconstrictor concentration of epinephrine in human skin for a range of doses of bupivacaine and its less-vasodilatory S(-) isomer, levobupivacaine. We injected combinations of 0.125%, 0.25%, and 0.75% bupivacaine and levobupivacaine with 1.25, 2.5, and 5 µg/mL epinephrine into the forearm skin of 10 healthy volunteers and measured the resulting blood flow changes over 1 hour using laser Doppler imaging. All 3 concentrations of epinephrine produced marked vasoconstriction, both alone and in combination with all 3 doses of the anesthetics (P < .001 in all cases). There was almost no difference in effect between the 3 epinephrine concentrations. We conclude that 1.25 µg/mL epinephrine produces a comparable vasoconstrictor effect in human skin to that of higher concentrations when coinjected with clinical doses of bupivacaine and levobupivacaine and may be equally effective for infiltration anesthesia.

U2 - 10.1016/j.rapm.2004.04.011

DO - 10.1016/j.rapm.2004.04.011

M3 - Article

C2 - 15305248

SN - 1098-7339

VL - 29

SP - 307

EP - 311

JO - Regional Anesthesia and Pain Medicine

JF - Regional Anesthesia and Pain Medicine

IS - 4

T2 - Scottish Society for Experimental Medicine

Y2 - 22 November 2002 through 22 November 2002

ER -