The Effect of Mepivacaine and Lidocaine on Forearm Resistance and Capacitance Vessels in Man

Abstract

SUMMARY Mepivacaine and lidocaine were infused intravenously and into the brachial artery in healthy human subjects. The effects on arterial blood pressure, forearm blood flow, forearm vascular resistance and venous tone were studied. Intravenous infusion of mepivacaine at a rate of 0.25 mg per kg body weight per min during 20 minutes increased the mean arterial blood pressure, forearm blood flow and venous tone. Blockade of the sympathetic nerves to the arm abolished die effect on blood flow, while the increase in blood pressure and venous tone persisted. Intra‐arterial infusions of 0.5‐6 mg per min of mepivacaine increased the venous tone and decreased the forearm blood flow. The mean arterial blood pressure was unchanged, while the calculated forearm vascular resistance increased. Following sympadietic blockade, the effect on forearm vascular resistance and blood flow was almost completely eliminated, while the increase in venous tone persisted. Intra‐arterial infusion of 1‐3 mg per min of lidocaine increased the venous tone, but did not significantly influence die arterial blood pressure of forearm blood flow. ZUSAMMENFASSUNG Mepivacain und Lidocain wurden gesunden Versuchspersonen sowohl intravenos als auch in die Armaterie infundiert. Dabei wurde die Wirkung auf den arteriellen Blutdruck, die Durchblutung des Unterarmes, der Gefass‐widerstand des Unterarmes und auch der Venentonus untersucht. Die intra venose Infusion von Mepivacain mit einer Geschwindigkeit von 0,25 mg pro kg Korpergewicht und Minute wahrend 10 Minuten erhohte den mittleren arteriellen Blutdruck, die Durchblutung des Unterarmes und den Venentonus. Blockade der sympadiischen Nerven des Armes loschte die Wirkung auf die Durchblutung aus, wahrend der erhohte Blutdruck und Venentonus bestehen blieben. Intraarterielle Infusion von Mepivacain 0,5‐0,6 mg pro Minute er‐hohten den Venentonus und verminderten die Durchstromung des Unterarmes. Der mittlere arterielle Blutdruck blieb unverandert, wahrend der er‐rechnete Gefasswiderstand des Unterarmes anstieg. Nach Sympathikusblockade verschwand die Wirkung auf den Gefasswiderstand des Unterarmes und auf die Durchblutung nahezu vollstandig, wahrend der erhohte Venentonus bestehen blieb. Die intraarterielle Infusion von Lidocain 1‐3 mg/Minute erhohte wohl den Venentonus, hatte aber keinen signifikanten Einfluss auf den arteriellen Blutdruck und die Durchblutung des Unterarmes.

Clinical Pharmacokinetics of Epidural and Spinal Anaesthesia

“…Local anaesthetics can also alter local perfusion by a direct action on vascular smooth muscle, resulting in either vasoconstriction or vasodilatation, depending upon the local anaesthetic agent, its concentration and stereochemical configuration, the site of injection, the type of blood vessel (capacitance or resistance) and pre-existing vascular tone (Aps & Reynolds 1976, 1978Blair 1975;Fairley & Reynolds 1981;Johns et al 1985Johns et al , 1986Jorfeldt et al 1970). Other factors that can influence local perfusion are hypovolaemia, local and systemic effects of added vasoconstrictors, systemic effects of local anaesthetics, effects of systemically administered drugs and cardiovascular changes due to pregnancy or disease, etc.…”

Venous Response After Lidocaine Administration in Arm Veins

“…Furthermore, the relationship between Pv and venous diameter demonstrated by cinephlebography does not support the belief that the Pv response following small doses of lidocaine administrations in vivo could be caused by the stimulating effect of local anesthetics. Consequently, it might be possible to suggest that the explanation that is presently given and accepted for the increase of venous tone after intravenous and intraarterial infusion of local anesthetics in normal subjects 4 needs to be reevaluated in the light of the research noted above.…”

“…4 We measured forearm blood flow in normal and hypertensive groups. Significant changes in forearm blood flow were not observed after 5 and 10 mg lidocaine administrations.…”

“…[1][2][3] Regarding the effects of local anesthetics on the circulation in human extremities, the increase of venous tone and the change in forearm blood flow with or without arterial pressure increase had been reported after small doses of intravenous and intraarterial infusion, these responses being attributed to the stimulating action of local anesthetics. 4 Based on that study, the increase of venous tone after intravascular administration of small-dose local anesthetics is generally accepted as resulting from the stimulating effect of the drug on the basal tone of VSM in contrast to the relaxant (spasmolytic) effect of toxic drug doses which can result in general hypotension due to peripheral vasodilation. 2,3 We previously reported on the change of venous pressure (Pv) after small-dose intravenous lidocaine administration in subjects with various diseases.…”

The Use of Intra-arterial Lidocaine to Control Pain Due to Aortofemoral Arteriography

“…The amount of contrast used for the pelvic and thigh arteriograms was equalized in order to compare them (TABLE II). Thirty milliliters of contrast material was used for each pelvic and liDOCAINE has been used widely as a local anes-... thetic (8), for intravenous injection to control cardiac arrhythmias (1,4), and for intra-arterial injection to relieve arterial spasm (6). The intra-arterial injection of procaine for the control of pain from aortography has been previously reported in 1966 by Curry et al (2).…”