Intravenous regional anesthesia

Intravenous regional anesthesia—injection of local anesthetic into a suitable vein supplying the limb to be anesthetized the blood flow from this limb is then restricted by a tourniquet... 

With local infiltration, toxic side-effects like convulsions and cardiovascular collaps occur in the dose range of 2.5 to 3 mg/kg body weight. Because of its systemic toxicity, bupivacaine is contraindicated for intravenous regional anesthesia. 

Brachial plexus anesthesia Buccal anesthesia Caudal anesthesia Cervical plexus anesthesia Dental anesthesia Digital anesthesia Epidural anesthesia Intercostal nerve anesthesia Interpleural anesthesia Intra-articular anesthesia Intradermal anesthesia Intrathecal (spinal) anesthesia Intravenous regional anesthesia Laryngeal anesthesia Lumbar plexus anesthesia Nasal anesthesia Neck anesthesia Obstetric anesthesia Ocular anesthesia Oropharyngeal anesthesia Otic anesthesia Paravertebral anesthesia Perianal anesthesia Peritonsillar anesthesia Respiratory anesthesia Sciatic nerve anesthesia Stellate ganglion anesthesia... 

Systemic toxic reactions are the most common complications of intravenous regional anesthesia, and they occur soon after the tourniquet is released. In cases of early accidental tourniquet release or rupture, deaths have resulted prilocaine seems to be the safest agent for this technique (271). 

A study of hdocaine toxicity in intravenous regional anesthesia showed that two of 24 patients who were given 0.5% lidocaine 40 ml for carpal tunnel decompression had serum hdocaine concentrations above the target range 2 minutes before and 2, 5, and 10 minutes after distal tourniquet deflation (274). However, no patients had signs of central nervous system or cardiovascular toxicity. 

Chloroprocaine, because of its rapid onset and ester hydrolysis, should be the ideal agent for intravenous regional anesthesia. However, there are reports that it can cause endothelial damage and dysrhythmias after tourniquet deflation (275). 

Phlebitis seems to have been triggered by intravenous regional anesthesia in a 32-year-old smoker who was also taking oral contraceptives (276). 

When 20 patients each received 40 ml of 0.5 % chloropro-caine or 0.5 % lidocaine for intravenous regional anesthesia, chloroprocaine caused a significantly higher incidence of a metallic taste (22 versus 0%) than hdocaine when the study was repeated using alkahnized instead of plain chloroprocaine, there was no significant difference between the groups (280). 

Lang SA. Intravenous regional anesthesia. Anesth Analg 1998 86(6) 1334-5. 

Chan VW, Weisbrod MJ, Kaszas Z, Dragomir C. Comparison of ropivacaine and lidocaine for intravenous regional anesthesia in volunteers a preliminary study on... 

Cherng CH, Wong CS, Ho ST. Acute aphesia following tourniquet release in intravenous regional anesthesia with 0.75% lidocaine. Reg Anesth Pain Med 2000 25(2) 211-12. 

Hartmannsgruber MW, Halaszynski TM. Ropivacaine 0.2% and lidocaine 0.5% for intravenous regional anesthesia in outpatient surgery. Anesthesiology 2001 95(3) 627-31. 

Lavin PA, Henderson CL, Vaghadia H. Non-alkalinized and alkalinized 2-chloroprocaine vs lidocaine for intravenous regional anesthesia during outpatient hand surgery. Can J Anaesth 1999 46(10) 939-45. 

Reuben SS, Steinberg RB, Lurie SD, Gibson CS. A dose-response study of intravenous regional anesthesia with meperidine. Anesth Analg 1999 88(4) 831-5. 

Intravenous regional ane.sthesia is used to anesthetize a large region, such us a limb. The anesthetic is injected into a suitable vein in a limb that has had its blood flow restricted by a tourniquet. The efficiency and safety of the technique depends on preventing arterial flow for the duration of the anesthesia. Lignocaine is frequently used to produce intravenous regional anesthesia, but bupivacaine is not approved for this purpose because of its long duration of action. 

Local anesthetics are used to locally anesthetize a wide range of specific body parts or areas to allow painless surgery. Local anesthetics are most commonly used for dental procedures and repair of lacerations. They can also be used to provide neural blockade for larger, more painful procedures. Sites of LA application include localized injection, peripheral nerve blocks as well as central nerve blockade. The only safe agents which can be utilized for intravenous regional anesthesia (Bier block) are lidocaine and prilocaine. Other typical indications are outlined in Table 64.1. 

For intravenous regional anesthesia, lidocaine is administered in 0.5% solution. For peripheral neural blockade, the 2% solution with or without epinephrine is most commonly administered to provide fastest onset of action as well as maximal surgical motor blockade. More dilute concentrations such as 1-1.5% may also be administered, but provide less motor blockade than the 2% solution. 

Ketamine has also been studied as an adjuvant to lidocaine intravenous regional anesthesia for hand surgery in 40 patients who received ketamine 0.1 mg/kg either as an adjuvant to the lidocaine or as an intravenous injection [26 ]. There were no significant differences in tourniquet pain or opiate requirements, either intraoperatively or during the recovery period. There were no difference in the incidence of psychotomimetic effects and satisfaction was high in both groups. The authors felt that it would be unethical to include a control group, as ketamine has already been shown to be superior to placebo. However, this makes the conclusions hard to interpret. 

Viscomi CM, Friend A, Parker C, Murphy T, Yamell M. Ketamine as an adjuvant in lidocaine intravenous regional anesthesia a randomized, double-blind, systemic control trial. Reg Anesth Pain Med 2009 34(2) 130-3. 

In a review of the literature on adverse events associated with intravenous regional anesthesia the author concluded that Bier s block is safe when anesthetic doses are kept low [46 ]. Seizures have been reported at doses as low as 1.4 mg/kg of hdocaine, 4 mg/kg of prilocaine, and 1.6 mg/kg of bupivacaine. Serious cardiac events have only been reported with hdocaine and bupivacaine. 

A 60-year-old women underwent intravenous regional anesthesia with 3 mg/kg of prilocaine 0.5% diluted with saline to a total of 40 ml for surgical treatment of carpal tunnel syndrome and 3 minutes after injection developed severe erythema and edema in the limb below the tourniquet. Intravenous hydrocortisone was started and the tourniquet was released after 20 minutes. All the skin signs disappeared within 1 hour and there were no systemic reactions after release of the tourniquet. A skin prick test later confirmed allergy to prilocaine. 

Guay J. Adverse events associated with intravenous regional anesthesia (Bier block) a systematic review of complications. J Clin Anesth 2009 21(8) 585-94. 

Dogramaci Y, Dogramaci AC, Esen E, Korkmaz T. Severe allergic reactions to prilocaine during intravenous regional anesthesia. Eur J Dermatol 2008 18(4) 462-3. 

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