Lidocaine for Carpal Tunnel Release

For Carpal Tunnel Release, lidocaine is commonly used as a local anesthetic, often without epinephrine. The maximum volume that can be injected depends on the concentration used and the patient's weight, but here are the standard references:

✅ Maximum recommended dose of lidocaine without epinephrine: 4.5 mg/kg (up to a maximum of 300 mg in adults).

💉 Common concentrations: 1% lidocaine = 10 mg/ml

2% lidocaine = 20 mg/ml

🔢 Practical example: For a 70 kg adult:

Max dose: 70 kg × 4.5 mg = 315 mg (but recommended not to exceed 300 mg)

With 1% lidocaine: 300 mg / 10 mg/ml = 30 ml maximum

With 2% lidocaine: 300 mg / 20 mg/ml = 15 ml maximum

🛠️ In surgical practice: For carpal tunnel release, 3 to 10 ml of 1% lidocaine is typically used, depending on the technique (local infiltration or regional block), with or without epinephrine.

With epinephrine, a higher dose (up to 7 mg/kg) is allowed, but it’s less common in this surgery due to the risk of digital ischemia.

Advantages:

Faster onset: Lidocaine works quickly (within 2–5 minutes), making it ideal for procedures where immediate numbness is needed. Effective for short procedures: Since carpal tunnel release is a relatively short procedure (typically 15–30 minutes), lidocaine’s duration (1–2 hours) is usually sufficient for the duration of the surgery. Lower risk of toxicity: Lidocaine is less potent than bupivacaine, with a lower risk of systemic toxicity, making it a safer option for shorter procedures. Disadvantages:

Shorter duration of pain relief: Lidocaine will wear off within a couple of hours after the procedure, so the patient may need post-operative pain management sooner. Bupivacaine for Carpal Tunnel Release: Advantages:

Longer duration of action: Bupivacaine provides extended anesthesia (4–6 hours or longer), offering better post-operative pain control, which can reduce the need for pain medication immediately after surgery. Extended post-operative comfort: Because bupivacaine lasts longer, it is often chosen when prolonged pain relief is desired, especially for outpatient procedures like carpal tunnel release. Disadvantages:

Slower onset: Bupivacaine takes longer to work (5–10 minutes), so it may delay the start of the procedure slightly. Higher risk of toxicity: Bupivacaine has a greater risk of systemic toxicity if not dosed carefully, so it requires more caution during administration. Combination Approach: In many cases, both lidocaine and bupivacaine are used together to optimize the benefits of each:

Lidocaine provides quick onset to start the surgery promptly. Bupivacaine ensures longer-lasting pain relief after the procedure. Recommendation: If quick anesthesia onset is important and the procedure is expected to be relatively short, lidocaine alone may be sufficient. If prolonged post-operative pain relief is a priority, bupivacaine (or a combination of lidocaine and bupivacaine) is often the preferred choice for carpal tunnel release. The combination approach is commonly favored for carpal tunnel release, as it offers the best of both worlds: immediate numbness and longer post-operative pain control.