Local anaesthetics reversibly block nerve transmission, when applied to a limited area of the body. They bind to the sodium channels in the nerve membrane and prevent the entry of sodium ions in response to the membrane’s deplorization. A vasoconstrictor like Adrenaline added to a local anaesthetic may significantly prolong the anaesthetic’s duration of action by reducing the blood flow around the injection site. This in turn may reduce the local anaesthetic’s peak plasma concentration and the risk of adverse systemic reactions.
Local Anaesthesia by infiltration or nerve block injection.
Xicaine is contraindicated in patients with known hypersensitivity to local anaesthetic of amide type, or the presence of vasoconstrictor. Adrenaline is contraindicated in patients with arterial hypertension, coronary disease, valvular cardiac disease.
Dosage and administration:
Adults :2ml is generally sufficient. 4ml may be used in the case of large interventions. However, 4 to 6ml may be used if deemed necessary for prolonged procedures.
Adolescents between 14 to 17 and the Elderly : Usual dose 1.8ml. Do not exceed 3.75ml.
Children between 6 and 14 :Usual dose 1 to 1.5ml. Do not exceed 2.5ml.