Lidocaine Bupivacaine

Amide-type agents include articaine, lidocaine, bupivacaine, prilocaine, mepivacain and ropiva-caine. These are metabolized in the liver by microsomal enzymes with amidase activity. The amide group is preferred for parenteral and local use. If by accident rapidly administered intravascularly these agents, especially bupivacaine but also lidocaine, can produce serious and potentially lethal adverse effects including convulsions and cardiac arrest. They can more easily accumulate after multiple administrations. Intravenous lidocaine is sometimes used for regional anesthesia, for infiltration procedures, for the induction of nerve blockade and for epidural anesthesia. However, it is also used as an antiarrhythmic. Bupivacaine is a long-acting local anesthetic used for peripheral nerve blocks and epidural anesthesia. 

Amide linked local anaesthetics e.g. lidocaine, bupivacaine, dibucaine, prilocaine, ropivacaine. 

Topical local anesthesia is often used for eye, ear, nose, and throat procedures. Satisfactory topical local anesthesia requires an agent capable of rapid penetration across the skin or mucosa, and with limited tendency to diffuse away from the site of application. Cocaine, because of its excellent penetration and local vasoconstrictor effects, has been used extensively for ear, nose and throat (ENT) procedures. Cocaine is somewhat irritating and is therefore less popular for ophthalmic procedures. Recent concern about its potential cardiotoxicity when combined with epinephrine has led most otolaryngology surgeons to switch to a combination containing lidocaine and epinephrine. Other drugs used for topical anesthesia include lidocaine-bupivacaine combinations, tetracaine, pramoxine, dibucaine, benzocaine, and dyclonine. 

The tests allow judgement of the propensity of local anesthetics to induce symptoms of hepatic porphyria. The local anesthetics lidocaine, bupivacaine, etido-caine, mepivacaine, prilocaine and pyrocaine belong to this group, but procaine, butacaine, oxybuprocaine, proxymethacaine and tetracaine had no (or very slight) porphyrinogenic effect. 

Bulk TLC Dissolve in H20, apply, spray with Na bicarbonate solution followed by acetic anhydride, heat Silica HCOOH-acetone-CH2Cl2 (0.5 50 50) Ethylenediamine/ ferric cyanide EP, pt. 11-7, pp. 254-3, noradrenaline also assayed, HPLC, resolved from lidocaine/ bupivacaine [130] [6]... 

Infusions of 0.25% bupivacaine into pig coronary arteries caused ventricular fibrillation at lower rates of infusion than 0.25% bupivacaine with 1% lidocaine (10). The lidocaine/bupivacaine mixture did not have a greater myocardial depressant effect than bupivacaine alone. The authors suggested that when regional anesthesia requires high doses of local anesthetics, bupivacaine should not be used alone but in a mixture with lidocaine, and that lidocaine should be useful in the management of bupivacaine-induced ventricular fibrillation. 

Retrobulbar anesthesia can lead to serious systemic toxicity. However, in animal studies accidental intravit-reous spread of lidocaine, bupivacaine, or a mixture of the two did not cause long-term retinal damage (308). 

Radwan lA, Saito S, Goto F. The neurotoxicity of local anesthetics on growing neurons a comparative study of lidocaine, bupivacaine, mepivacaine, and ropivacaine. Anesth Analg 2002 94(2) 319-24. 

Lidocaine, bupivacaine, mepivacaine, procaine, cocaine Depolarizing D-tubocurarine, atracurium, pancuronium Nondepolarizing succinylcholine... 

Local anaesthetics prevent nerve transmission by blocking sodium ion channels from the inside of the neuron. Sensory nerves that carry the stimulus of pain are the most sensitive to the actions of local anaesthetics. Accidental overdose can cause systemic effects including cardiorespiratory depression and loss of consciousness. Lidocaine is probably the most commonly used local anaesthetic. Qualified, registered podiatrists are allowed to access and administer lidocaine, bupivacaine, prilocaine, mepivacaine, levobupivacaine and ropivacaine. 

The choice of local anesthetic and the amount and concentration administered are determined by the nerves and the types of fibers to be blocked, the required duration of anesthesia, and the size and health of the patient. For blocks of 2-4 hours, lidocaine (1-1.5%) can be used in the amounts recommended above (see Infiltration Anesthesia ). Mepivacaine (up to 7 mg/kg of a 1-2% solution) provides anesthesia that lasts about as long as that from lidocaine. Bupivacaine (2-3 mg/kg of a 0.25-0.375% solution) can be used when a longer duration of action is required. Addition of 5 pg/mL epinephrine slows systemic absorption and, therefore, prolongs duration and lowers the plasma concentration of the intermediate-acting local anesthetics. 

Amides lidocaine, bupivacaine, mepivacaine are metabolized by liver amidases Mechanisms ... 

Esters and Amides Local anesthetics that are esters have just one "i" in their names (e.g., procaine, cocaine) amide local anesthetics have more than one "i" (e.g., lidocaine, bupivacaine). 

B. Propofol levels may be increased by lidocaine, bupivacaine, and halothane, producing an increased hypnotic effect. 

Lidocaine, bupivacaine, noscapine, PV CZE-UV SPE using Oasis HLB cartridges 300 ng/mL Urine samples [110]... 

Specific nerve block (brachial plexus, ankle, intrabulbar, dental, etc) Lidocaine Bupivacaine Ropivacaine Levobupivacaine... 

One mechanism could be related to the pro-inflammatory effects of bupivacaine and lidocaine. Bupivacaine potentiates nitric oxide synthase-2 (NOS2) activity in rat glial cells, stimulating inflammation through the production of nitric oxide [18 ] and lidocaine selectively upregulates pro-inflammatory proteins [19 ]. This might not be a class effect of local anesthetics, as newer local anesthetics, such as ropivacaine, do not promote inflammatory processes [20, 21, 22 ]. 

A 54-year-old woman, who had used lidocaine cream intermittently for over 1 year for hemorrhoids, suddenly developed a severe perianal bullous eczematous type IV reaction a few days after applying the cream again. Subsequent patch testing with a local anesthetic series showed cross-reactivity to the amide local anesthetics lidocaine, bupivacaine, mepivacaine, and prilocaine. There was no cross-reactivity with an ester-type anesthetic. 

Also analyzed articaine, prilocaine, o-toluidine, lidocaine, bupivacaine, etidocaine, dibucaine, caffeine, amphetamine, ephedrine, epinephrine, morphine, monoacetylmor-phine, diamorphine, ethylmorphine, codeine, acetylcodeine... 

Figure 13.19 Chemical formulae of lidocaine, bupivacaine, mepivacaine and tricaine mesylate.

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