II. Indications
-
Procedural Anesthesia
- Typically performed for orthopedic extremity surgeries
- Not recommended for procedures lasting more than 1.5 hours
III. Contraindications
- Ischemic limb or crush injury to target limb
- Neurovascular deficit in target limb
- Raynaud Disease
- Thromboangiitis Obliterans (Buerger's Disease)
- Seizure Disorder
- Uncontrolled Hypertension
IV. Complications
- Local Anesthetic Systemic Toxicity (LAST Reaction)
- Inadequate Anesthesia
-
Compartment Syndrome
- Rare case reports related to concentrated Anesthetic solution
V. Preparation
- Intravenous Access at distal aspect of target extremity
-
Anesthetic
- Lidocaine 0.5% without Epinephrine (if not available, dilute 1% Lidocaine to 0.5%)
- Upper extremity dose: 30-50 ml (up to 1.5 mg/kg)
- Lower extremity dose: 100 ml (up to 1.5 mg/kg)
- Automatic Pneumatic Tourniquet
- Consider using 2 adjacent Tourniquets to reduce Tourniquet pain
- Apply the second Tourniquet, immediately distal to first, over cotton wrap, at 10 minutes after the first applied
VI. Technique
- Apply cotton padding (web roll or similar splint padding) around arm in region where Tourniquet will be applied
- Position Tourniquet over the cotton padding and keep in non-inflated state
- Exsanguinate the arm
- Elevate the arm and wrap an Esmarch bandage (or similar soft Rubber wrap) from distal fingers to Tourniquet proximally
- Inflate Pneumatic Tourniquet to 100 mmHg over systolic Blood Pressure
- Consider applying a second adjacent, distal Tourniquet over cotton wrap after first 10 minutes (see preparation above)
- Slowly inject Anesthetic within distal IV on target extremity
- Lidocaine 0.5% without Epinephrine (see dosing under preparation as above)
- Releasing the block on procedure completion
- Deflation recommendations are to prevent Local Anesthetic Systemic Toxicity (LAST Reaction)
- Leave the Tourniquet inflated for at least 20 minutes after Anesthetic injection
- Deflate the Tourniquet for 5 seconds, reinflate for 2 minutes, and perform twice before final deflation
- If Tourniquet has been in place for more than 30 minutes, single deflation is sufficient
VII. Resources
- Intravenous Regional Anesthesia (Nysora)
VIII. References
- Warrington (2021) Crit Dec Emerg Med 35(6): 24