LEVOBUPIVACAINE

Indications

• Local anaesthesia
• Surgical anaesthesia
• Acute postoperative pain
• Obstetrical procedures

Dosage

Children: Dosing in children should be determined according to the child's physical status and the nature of the procedure, as specified in the BNF for Children.

Adults: For surgical anaesthesia via lumbar epidural, the typical adult dose is 75-150 mg, administered over 15-20 minutes using a 5 mg/mL (0.5%) solution. For intrathecal injection, 15 mg is recommended. For local infiltration, doses may range from 2.5 to 150 mg, administered using a 2.5 mg/mL (0.25%) solution. The maximum daily dose should not exceed 400 mg.

Mechanism of action

Levobupivacaine blocks the generation and conduction of nerve impulses by binding to the intracellular portion of sodium channels in nerve cells. This action prevents sodium influx, which is essential for depolarization, thereby increasing the threshold for electrical excitation and slowing nerve impulse propagation.

Pharmacodynamics

Levobupivacaine induces local or regional anesthesia by effectively blocking nerve conduction. Its anesthetic effects are influenced by the diameter and myelination of nerve fibers, with a greater effect on larger, myelinated fibers. The drug is utilized in various clinical settings including surgical procedures, providing pain relief and facilitating interventions by maintaining patient comfort.

Pharmacokinetics

Levobupivacaine is absorbed following local administration, with its pharmacokinetic profile influenced by the route of administration and the site of injection. The drug undergoes hepatic metabolism, primarily by cytochrome P450 enzymes, and is excreted in urine. Its half-life and systemic exposure may vary based on patient factors, including hepatic and renal function.

Contra-indications

• Hypersensitivity to levobupivacaine or other local anesthetics
• Infection or inflammation at the injection site
• Severe cardiovascular disease
• Complete heart block
• Severe hepatic impairment

Adverse effects

• Neurological effects (e.g., dizziness, headache, back pain)
• Cardiovascular effects (e.g., hypotension, arrhythmias)
• Nausea
• Apnoea
• Angioedema
• Bradycardia
• Neonatal respiratory depression (after epidural block)

Interactions

• Other local anesthetics
• Drugs that affect cardiac conduction

Precautions

• Use with caution in elderly patients or those with debilitation
• Careful monitoring in patients with impaired cardiac conduction or respiratory function
• Avoid excessive dosage in obese patients, dosing should be based on ideal body weight
• Should only be administered by trained personnel with adequate resuscitation equipment available

Pregnancy

Use only if potential benefit outweighs risk, particularly in the first trimester. Caution advised due to potential toxicity in animal studies.

Breast-feeding

Amount too small to be harmful.

Storage

Protect from light.

Formulations

• Solution for injection (various concentrations including 0.5% and 0.75%)

Mechanism of action

Local anesthetics such as Levobupivacaine block the generation and the conduction of nerve impulses, presumably by increasing the threshold for electrical excitation in the nerve, by slowing the propagation of the nerve impulse, and by reducing the rate of rise of the action potential. In general, the progression of anesthesia is related to the diameter, myelination and conduction velocity of affected nerve fibers. Specifically, the drug binds to the intracellular portion of sodium channels and blocks sodium influx into nerve cells, which prevents depolarization.

Pharmacodynamics

Levobupivacaine, a local anesthetic agent, is indicated for the production of local or regional anesthesia or analgesia for surgery, for oral surgery procedures, for diagnostic and therapeutic procedures, and for obstetrical procedures.