LOCAL OR REGIONAL ANAESTHESIA, NERVE BLOCKS, EPIDURAL AND CAUDAL ANAESTHESIA
Adult:
Lidocaine HCl 20 mg/ml+adrenaline 5 mcg/ml. Dosage depends on several factors such as route, type and extent of surgical procedure, duration of anaesthesia and patient's condition and age.)
Max Dosage: adrenaline: 7mg/kg and not more than 500mg.
Injection
LOCAL OR REGIONAL ANAESTHESIA, NERVE BLOCKS, EPIDURAL AND CAUDAL ANAESTHESIA
Child:
3 mth-12 yr: max dose 3 mg/kg. Ideal body weight should be used in children with high body weight.
Precautions
Epilepsy; impaired cardiac conduction; CHF, DM; closed angle glaucoma; impaired liver function (if site of administration is likely to result in high blood levels); severe renal dysfunction; local anaesthetic effect may be reduced if injected into an inflamed or infected area; cerebrovascular insufficiency; hyperthyroidism. Neonates, elderly, patients in poor general condition (optimise patient's condition before major block), pregnancy.
Potentially Life-threatening
Adverse Drug Reactions
Severity of adverse effects in CNS and CVS related to blood levels of lidocaine; effects more likely to occur after systemic administration rather than infiltration. CNS toxicity (due to inadvertent IV admin), medullary depression with tonic & clonic convulsions; ventricular fibrillation; severe hypertension with cerebral haemorrhage and pulmonary oedema; unconsciousness; possibly respiratory arrest. Allergic reactions including anaphylactic symptoms and possibly life threatening asthmatic episodes in susceptible patients may occur due to sodium metabisulphate constituent. Central nerve blocks may cause CV depression (especially in hypovolaemia). Retrobulbar inj may reach subarachnoid space causing CV collapse, apnoea, convulsions, temporary blindness. Paracervical block may cause foetal bradycardia/tachycardia (careful monitoring of foetal heart rate is necessary).
Adverse Drug Reactions
Epilepsy; impaired cardiac conduction; CHF, DM; closed angle glaucoma; impaired liver function (if site of administration is likely to result in high blood levels); severe renal dysfunction; local anaesthetic effect may be reduced if injected into an inflamed or infected area; cerebrovascular insufficiency; hyperthyroidism. Neonates, elderly, patients in poor general condition (optimise patient's condition before major block), pregnancy.
Interactions
Significance of interaction depends on route of delivery and systemic exposure; lidocaine prolongs duration of action of suxamethonium; benzodiazepines & barbiturates raise the convulsive threshold to lidocaine; vasopressors potentiate pressor effects of adrenaline; BP may increase with non-selective β-blockers, TCAs, halogenated inhalational anaesthetics and α-blockers; general anaesthetics may increase sensitivity of myocardium to dysrhythmic effects of epinephrine; lidocaine may increase levels and effects of benzodiazepines, calcium channel blockers, ciclosporine, aminophylline, fluvoxamine, mexiletine, mirtazapine, ropinirole, theophylline, trifluoperazine, dextromethorphan, fluoxetine, nefazodone, paroxetine, risperidone, TCAs and venlafaxine. Levels and effects of lidocaine may be increased by propranolol, chlorpromazine, delavirdine, fluoxetine, miconazole, pergolide, quinidine, quinine, ritonavir, ropinirole, cimetidine, azole antifungals, clarithromycin, diclofenac, doxycycline, erythromycin, isoniazid, nicardipine and verapamil. Lidocaine may decrease levels and effects of codeine, hydrocodone, oxycodone, tramadol, carbamazepine, nafcillin, nevirapine, phenobarbital, phenytoin and rifamycins. Midazolam, cisapride, ergot alkaloids, lovastatin and simvastatin are not recommended in combination with lidocaine.
