Regional anaesthesia

It is indicated as a narcotic analgesic supplement in general or regional anaesthesia, as an anaesthetic agent with oxygen and skeletal relaxant in selected high risk patients (e.g. open heart surgery). 

Lignocaine injections are indicated for production of local or regional anaesthesia by infiltration techniques such as percutaneous injection, peripheral nerve block, spinal or subarachnoid block. 

Intra-arterial injection of thiopentone is a serious complication as crystals of the thiobarbiturate can form in the arterioles and capillaries, causing intense pain, vasoconstriction, thrombosis, and even tissue necrosis. Accidental intra-arterial injections should be treated promptly with intra-arterial administration of a vasodilator (papaverine 20 mg) and lignocaine (lidocaine) Note leave the needle/cannula in the artery), as well as a regional anaesthesia-induced sympathectomy (stellate ganglion block, brachial plexus block) and anticoagulation with intravenous heparin. The risk of ischaemic damage is much higher with a 5% solution and the use of this concentration is not recommended. 

Local anaesthetics can be applied topically, deposited around peripheral nerves, or infiltrated into tissues. Central neural blockade can be produced by injection into the subarachnoid or epidural spaces. Less common uses are for intravenous regional anaesthesia and attenuation of cardiovascular responses to tracheal intubation. The membrane-stabilising effect of local anaesthetics has been utilised in the treatment of myocardial arrhythmias. 

Lidocaine is used for all forms of infiltration anaesthesia, in addition to peripheral, regional, spinal and epidural block. Unlike bupivacaine, it is suitable for use in intravenous regional anaesthesia. Duration of anaesthesia is about 1 hour but this can be prolonged to 2 hours by the addition of adrenaline. The maximum doses are shown in Table 5.2. 

Prilocaine is suitable for most types of local anaesthetic block but is not suitable for epidural use in obstetrics because of the need for repeat administration. Its main uses are for infiltration anaesthesia and intravenous regional anaesthesia where its low toxicity makes it the drug of choice. Levobupivacaine... 

Metaraminol is a catecholamine which acts predominantly at ol adrenoceptors on vascular smooth muscle, and is virtually devoid of p-receptor activity. It is used to treat hypotension during general and regional anaesthesia. Methoxamine is a vasopressor with a similar pharmacological profile. 

Karalezli N, Karalezli K, Iltar S, et al. Results of intravenous regional anaesthesia with distal forearm application. Acta Orthop Belg. 2004 70 401-405. 

Servin FS, Raeder JC, Merle JC, Wattwil M, Hanson AL, Lauwers MH, Aitkenhead A, Marty J, Reite K, Martisson S, Wostyn L. Remifentanil sedation compared with propofol during regional anaesthesia. Acta Anaesthesiol Scand 2002 46(3) 309-15. 

Naguib M, Magboul MM,Jaroudi R, et al.Adverse effects and drug interactions associated with local and regional anaesthesia. Drug Saf 1998 18 221-250. 

In selected cases the full range of techniques of local and regional anaesthesia may be used, including extradural and intrathecal morphine (p. 360). 

Regional anaesthesia requires considerable knowledge of anatomy and attention to detail for both success and safety. 

Intravenous. A double cuff is applied to the arm, inflated above arterial pressure after elevating the limb to drain the venous system, and the veins filled with local anaesthetic, e.g. 0.5-1% lidocaine without adrenaline (epinephrine). The arm is anaesthetised in 6-8 min, and the effect lasts for up to 40 min if the cuff remains inflated. The cuff must not be deflated for at least 20 minutes. The technique is useful in providing anaesthesia for the treatment of injuries speedily and conveniently, and many patients can leave hospital soon after the procedure. The technique must be meticulously conducted, for if the full dose of local anaesthetic is accidentally suddenly released into the general circulation severe toxicity and even cardiac arrest may result. Bupivacaine is no longer used for intravenous regional anaesthesia as cardiac arrest caused by it is particularly resistant to treatment. Patients should be fasted and someone skilled in resuscitation must be present. 

Prilocaine is used similarly to lidocaine (t,i 1.5 h), but it is slightly less toxic. It used to be the preferred drug for intravenous regional anaesthesia but it is... 

Pitkanen MT, Rosenberg PH, Pere PJ, Tuominen MK, Seppala TA. Fentanyl-prilocaine mixture for intravenous regional anaesthesia in patients undergoing surgery. Anaesthesia 1992 47(5) 395-8. 

Coleman M, Kelly DJ. Local anaesthetic toxicity in a pregnant patient undergoing lignocaine-induced intravenous regional anaesthesia. Acta Anaesthesiol Scand 1998 42(2) 267-9. 

Dalens BJ, Mazoit JX. Adverse effects of regional anaesthesia in children. Drug Saf 1998 19(4) 251-68. 

Carling A, Simmonds M. Complications from regional anaesthesia for carotid endarterectomy. Br J Anaesth 2000 84(6) 797-800. 

Dick W. Gefahrdung der Mutter durch Allgemeinanaesthesie und Regionalanaesthesie. [Maternal risk from general anaesthesia and regional anaesthesia.] Anaesthesist 1980 29(5) 219-25. 

Abdulla W, Kroll S, Eckhardt-Abdulla R. Intravenous regional anaesthesia—a new approach in clinical application. Anasthesiol Intensivmed 2000 41 94-103. 

Kireker HD, Aynacioglu AS, Goksu S. Determination of 0.5% lidocaine serum concentrations and evaluation for toxicity in intravenous regional anaesthesia. Turk Anesteziyol Reanim 2000 28 211-16. 

Marrocco-Trischitta MM, Bandiera G, Camilli S, Stillo F, CirielU C, Guerrini P. Remifentanil conscious sedation during regional anaesthesia for carotid endarterectomy rationale and safety. Eur J Vase Endovasc Surg 2001 22(5) 405-9. 

Markham A, Faulds D. Ropivacaine. A review of its pharmacology and therapeutic use in regional anaesthesia. Drugs 1996 52(3) 429 9. 

McClellan KJ, Faulds D Ropivacaine An update of its use in regional anaesthesia. Drugs 60(5) ... 

Tliiopental sodium is a barbiturate which is administered intravoHnMy for the induction of general anaesthesia or for the production of ccmqrlete anaesdiesia of short duration [3]. Odier uses include the siq lementatirm of regional anaesthesia or low potency agoits such as nitrous oxide, the control of convulsive states and as a hypnotic [3,61]. In p chiatry it has found some use as an aid in diagnosis, and as a treatment of some disorders [61]. 

The authors of two of the reports cited here offer the opinion that general and regional anaesthesia may be provided safely without discontinuation of MAOI therapy, provided proper monitoring, adequate preparation, and prompt treatment of anticipated reactions are utilised . This implies that the possible interactions between the MAOI and other drugs are fully recognised, but be alert for the rare unpredictable response. The conclusion of another report was that patients on low-dose MAOIs could be safely anaesthetised. ... 

The neuromuscular blockade due to suxamethonium (succinyl-choline) can be increased and prolonged by lidocaine, procaine and possibly procainamide. These local anaesthetics all have some neuromuscular blocking activity and may theoretically also enhance the block produced by competitive neuromuscular blockers. Increased toxicity occurred when mivacurium and prilocaine were given together for regional anaesthesia. 

In a study of 10 healthy subj ects, prolonged muscle weakness and symptoms of local anaesthetic toxicity were experienced after deflation of the tourniquet when 40 mL of prilocaine 0.5% and mivacurium 600 micrograms were used together for intravenous regional anaesthesia of the forearm. Giving prilocaine or mivacurium alone did not produce these effects. The slow recovery suggested that mivacurium was not broken down in the ischaemic limb, but inhibition of plasma cholinesterase by prilocaine would not fully explain the prolonged weakness once the cuff was deflated. ... 

Honarmand A, Safavi MR. Comparison of prophylactic use of midazolam, ketamine, and ketamine plus midazolam for prevention of shivering during regional anaesthesia a randomized double-blind placebo controlled trial. Br J Anaesth 2008 101(4) 557-62. 

Gogarten W, Vandermeulen E, Van Aken H, Kozek S, Llau JV, Samama CM Regional anaesthesia and antithrombotic agents recommendations of the European Society of Anaesthesiology. Eur J Anaesthesiol 2010 27 999 1015. 

Forster JG, Rosenberg PH. Clinically useful adjuvants in regional anaesthesia Curr... 

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