Overview
Bupivacaine is a long-acting amide local anesthetic used for local infiltration, peripheral nerve blocks, epidural anesthesia, and spinal anesthesia. It provides prolonged anesthesia with a slow onset of action (5-10 minutes).
Mechanism of Action
Bupivacaine blocks voltage-gated sodium channels in neuronal cell membranes, inhibiting depolarization and propagation of action potentials, thereby preventing nerve signal transmission and producing local anesthesia.
Indications
- Local infiltration anesthesia
- Peripheral nerve blocks
- Epidural anesthesia
- Spinal anesthesia
- Postoperative pain management
Dosage
Dosage varies by route and procedure. Maximum recommended dose: 400 mg per 24 hours (or 2 mg/kg). For epidural anesthesia: 10-20 mL of 0.25% to 0.75% solution. Always use lowest effective dose.
Black Box Warning
WARNING: LOCAL ANESTHETIC TOXICITY. Bupivacaine can cause dose-related toxicity. Use in obstetrical paracervical block anesthesia is contraindicated. Use the lowest effective dose.
Contraindications
- Hypersensitivity to amide local anesthetics
- Severe hypotension
- Septicemia
- Infection at injection site
- Coagulopathy or anticoagulant therapy (for neuraxial blocks)
Side Effects
- Hypotension
- Bradycardia
- Nausea
- Vomiting
- Headache
- Back pain
- Urinary retention
- Paresthesia
- Seizures (with systemic toxicity)
- Cardiac arrest (with intravascular injection)
Interactions
- MAO inhibitors: increased risk of hypotension
- Beta-blockers: additive bradycardia
- Other local anesthetics: additive toxicity
- Vasoconstrictors (epinephrine): may enhance duration but increase cardiovascular effects