Bupivacaine
A long-acting amide local anesthetic for nerve blocks and epidurals, notable for cardiac arrest in overdose.
Drug card
- Class
- Local anesthetic
- How it works
- Blocking voltage-gated sodium channels so nerves cannot fire impulses
- Used for
- Nerve blocks and local infiltration for surgery
- Epidural pain relief in labor and after surgery
- Dental and oral surgery
- Known for
- Cardiac arrest that is hard to resuscitate
- Seizures from high blood levels
- Its name
- -caine means a local anesthetic
Study it as a flashcard, and it comes back before you forget it.
Mechanism of action
How does bupivacaine work?
Bupivacaine blocks sodium channels in nerve membranes, raising the threshold for excitation and slowing impulse conduction. Its block lasts longer than that of short-acting local anesthetics, and pain relief outlasts the return of sensation. At toxic blood levels it depresses cardiac conduction and excitability, causing AV block, ventricular arrhythmias and cardiac arrest.
Like other local anesthetics: Local anesthetics bind voltage-gated sodium channels in nerve membranes, so the action potential rises slowly or not at all and impulses stop. Fiber size and myelination set the order of block: pain goes first, then temperature, touch and position sense, and muscle tone last. Lidocaine and bupivacaine are amides, broken down by the liver; epinephrine is often added to slow absorption and lengthen the block.
Uses
What is bupivacaine used for?
- Nerve blocks and local infiltration for surgery
- Epidural pain relief in labor and after surgery
- Dental and oral surgery
Side effects
Side effects of bupivacaine
- Cardiac arrest that is hard to resuscitateKnown forSerious
- Seizures from high blood levelsKnown forSerious
- Ventricular arrhythmias and heart blockSerious
- Numb lips, metallic taste, tinnitus: early toxicity
- Restlessness, anxiety and dizziness
- Low blood pressure
- Slow heart rateSerious
- Breathing depression and arrestSerious
- MethemoglobinemiaSerious
- Urinary retention after epidural block
- Cartilage damage after infusion into a jointSerious
- Nausea and vomiting
Known for marks what an exam expects you to know it for.
Watch for
Cautions and what sets it apart
- Its strongest concentration is not used for obstetric epidurals, after reports of cardiac arrest.
- Contraindicated for IV regional anesthesia (Bier block) and obstetric paracervical block.
- Aspirate and give doses in steps; repeated doses build up, especially in liver disease.
- With epinephrine, MAOIs, tricyclics or nonselective beta blockers can cause severe high blood pressure.
Good to know: Its long action suits nerve blocks and epidurals, but an accidental intravascular dose can stop the heart, and resuscitation may be difficult or impossible.
Remember it
A way to remember it
Pain leaves first, muscle power last.
Local anesthetics block nerve fibers in an order set by their size and myelination, so sensation goes in turn: pain, temperature, touch, position sense, and finally muscle tone.
Written for biofideX
Its name
-caine means local anesthetic
Lidocaine and bupivacaine block sodium channels in nerves. Inside a name, -cain- marks class I antiarrhythmics such as flecainide and procainamide; lidocaine treats arrhythmias too.
- Every drug name stem
Its class
Local anesthetics
Other local anesthetics with a card:
Easily mixed up with sodium channel-blocking antiepileptics, class III antiarrhythmics and intravenous anesthetics.
Sources
Checked against
Written for biofideX in plain words, after checking these references:
For learning pharmacology, not for treatment decisions: no doses are given, and a prescriber, pharmacist or the product's own label is the word on any one patient. Spotted a mistake? Tell us and we'll correct it.
Anesthesia and muscle relaxants
Bupivacaine is one of 8 drugs practiced together here: their classes, how they work, what they treat and what they're known for.
Start Practicing