G-Lidocaine & Adrenaline

When working out a safe dose of lidocaine with adrenaline, you have to look at how fast the body absorbs and excretes it, as well as how potent it is. Other things count too: the patient's age, weight, physique and clinical condition, how vascular the area is where it will be applied, and how long it will be given. The dose is adjusted to the patient's response and the site of administration. Give the lowest concentration and the smallest dose that produces the effect needed.

For healthy adults, the individual maximum recommended dose should not exceed 7 mg/kg of body weight, and in general the maximum total dose should not exceed 500 mg. Children and elderly or debilitated patients need smaller doses, in keeping with their age and physical condition. In children the dose should be reduced according to age, body weight and physical condition.

In the USA, the following doses have been recommended for individual local anaesthetic procedures. For percutaneous infiltration anaesthesia the dose is 5 to 300 mg (1 to 60 mL of a 0.5% solution or 0.5 to 30 mL of a 1% solution). In peripheral nerve block the dose depends on the route of administration. For brachial plexus block, 225 to 300 mg (15 to 20 mL) is used as a 1.5% solution. For intercostal nerve block, 30 mg (3 mL) is given as a 1% solution. For paracervical block, a 1% solution is used at 100 mg (10 mL) on each side, repeated no more often than every 90 minutes. For paravertebral block, a 1% solution may be used in doses of 30 to 50 mg (3 to 5 mL). For pudendal block, a 1% solution is recommended at 100 mg (10 mL) on each side. For retrobulbar block, a 4% solution may be used in doses of 120 to 200 mg (3 to 5 mL). For sympathetic nerve block, a 1% solution is recommended, with 50 mg (5 mL) for cervical block and 50 to 100 mg (5 to 10 mL) for lumbar block.

For epidural anaesthesia, 2 to 3 mL of solution is needed for each dermatome to be anaesthetised. The usual total doses and recommended concentrations are these: for lumbar epidural, 250 to 300 mg (25 to 30 mL) as a 1% solution for analgesia, and 225 to 300 mg (15 to 20 mL) as a 1.5% solution or 200 to 300 mg (10 to 15 mL) as a 2% solution for anaesthesia. For thoracic epidural, a 1% solution may be used at doses of 200 to 300 mg (20 to 30 mL). In obstetric caudal analgesia, 200 to 300 mg (20 to 30 mL) is used as a 1% solution, and in surgical caudal anaesthesia a 1.5% solution may be used in doses of 225 to 300 mg (15 to 20 mL). For continuous epidural anaesthesia, the maximum doses should not be repeated more often than every 90 minutes.

A hyperbaric solution of 1.5% or 5% lidocaine hydrochloride in glucose 7.5% solution is available for spinal anaesthesia, and epinephrine (adrenaline) should not be used with it. During labour for a normal vaginal delivery, doses of up to 50 mg (1 mL) as a 5% solution and 9 to 15 mg (0.6 to 1 mL) as a 1.5% solution have been used. Up to 75 mg (1.5 mL) as the 5% solution has been used for caesarean section, and 75 to 100 mg (1.5 to 2 mL) for other surgical procedures.