Bupivacaine injection for local and regional anesthesia in adults

Bupivacaine hydrochloride injection is a local anesthetic used to provide anesthesia or pain relief in adults during surgery, dental procedures, diagnostic and therapeutic interventions, and obstetrical procedures. It is available in multiple concentrations for different types of nerve blocks and anesthesia techniques administered by injection.

Indicated in adults for producing local or regional anesthesia or analgesia in various medical settings, including:

• Surgical procedures requiring local or regional anesthesia
• Dental and oral surgery procedures
• Diagnostic and therapeutic interventions
• Obstetrical procedures (with restrictions on concentration)

Note that not all nerve blocks are appropriate due to associated risks, and specific concentrations are recommended for different blocks. The 0.75% concentration should not be used for obstetrical anesthesia.

Bupivacaine Hydrochloride

Bupivacaine blocks nerve impulse transmission by inhibiting sodium ion influx in nerve cells, which prevents the initiation and conduction of nerve signals, leading to loss of sensation and pain relief in the targeted area.

Dosage and administration considerations

• Not for intrathecal use.
• Avoid solutions with antimicrobial preservatives for epidural or caudal anesthesia.
• Use only clear, colorless solutions free of particulates.
• Mixing with other local anesthetics is not recommended due to insufficient safety data.
• Should be administered by experienced clinicians with immediate availability of emergency resuscitative equipment and drugs.
• Aspirate prior to and during injection to avoid intravascular or intrathecal injection, though negative aspiration does not guarantee safety.
• Avoid rapid injection of large volumes; use incremental dosing where feasible.
• Monitor cardiovascular, respiratory status and consciousness closely after each dose.
• Use lowest effective dose and concentration to minimize toxicity risk.

Concentration and dosage recommendations by type of block (adults)

*0.75% concentration is not recommended for obstetrical anesthesia.

Effect on motor function

• 0.25%: produces incomplete motor block; slower onset; suitable when muscle relaxation is not important.
• 0.5%: produces moderate to complete motor block; may be inadequate for complete muscle relaxation.
• 0.75%: produces complete motor block; used for abdominal surgery epidural blocks and retrobulbar anesthesia; not for obstetrical anesthesia.

Maximum doses

• Do not exceed 400 mg total dose in 24 hours.
• Doses may be repeated every 3 hours as needed.
• Addition of epinephrine may prolong anesthetic duration.

Example dosing ranges for adults

During epidural administration, incremental dosing of 3–5 mL with aspiration and vigilance for toxicity is required. In obstetrics, only 0.5% and 0.25% concentrations are used with maximum dosage intervals recommended.

• Obstetrical paracervical block anesthesia due to risk of fetal bradycardia and death.
• Intravenous regional anesthesia (Bier Block).
• Hypersensitivity to bupivacaine or any amide-type local anesthetic or components of the formulation.

Boxed Warning

There have been reports of difficult-to-resuscitate or fatal cardiac arrest during epidural anesthesia in obstetrical patients using the 0.75% concentration of bupivacaine. This risk is associated with systemic toxicity, often after unintended intravascular injection. The 0.75% concentration is not recommended for obstetrical anesthesia and should only be reserved for surgical procedures requiring high muscle relaxation and prolonged effect.

Additional precautions

• Monitor cardiovascular and respiratory vital signs and consciousness closely after injection due to risk of dose-related toxicity.
• Aspirate before each dose to avoid intravascular or intrathecal injection, though negative aspiration does not guarantee safety.
• Avoid use of multiple-dose vials containing preservatives for epidural or caudal anesthesia.
• Be aware of the additive toxic effects when used with other local anesthetics.
• Maintain readiness for immediate management of systemic toxic reactions, including seizures and cardiac arrest.
• Report and monitor for methemoglobinemia and chondrolysis (with intra-articular infusion, an unapproved use).
• Intravenous regional anesthesia (Bier Block) is contraindicated due to risk of cardiac arrest.

Systemic toxicity may cause central nervous system symptoms such as convulsions, drowsiness, respiratory depression, and cardiovascular symptoms including arrhythmias and cardiac arrest. Methemoglobinemia and chondrolysis have been reported but are rare.

The toxic effects of bupivacaine are additive with other local anesthetics, increasing the risk of systemic toxicity. Careful monitoring is required if used concomitantly.

Not recommended for obstetrical anesthesia when using the 0.75% concentration. Use of lower concentrations (0.25% or 0.5%) with careful dose and concentration control is recommended in obstetrical patients.

Overdose may cause symptoms of central nervous system toxicity including seizures, respiratory depression, coma, and cardiovascular collapse including arrhythmias and cardiac arrest. Immediate supportive measures including oxygen, cardiopulmonary resuscitation, and management of seizures are essential.

Visually inspect before use and do not administer if discolored or containing particulate matter. Discard unused portions of preservative-free single-dose vials after initial use.