This is a must memorize simple table of the toxic doses of local anesthetics. Toxicity of local anesthetics starts with slurred speech, lethargy to seizures and lethal cardiac dysrhythmias. There should be zero tolerance to actual cause toxicity when repairing a laceration or performing a fascia iliaca block.
Remember that a Bupivcaine solution 0.5% = 0.5 g/dL (%=g/dL) so a 70kg person, you can use a maximum of 2mg/kg x 70kg person. You can inject 140 mg in a 70kg person. This is a maximum volume injection of 28 mL if you were doing a fascia iliaca block. You can double the volume if you use a more dilute solution of 0.25%.
Local Anesthetic
mg/kg
Bupivacaine
2
Ropivacaine
3
Lidocaine
4
Lidocaine with Epinephrine
6
Prilocaine
6
Treatment for cardiac dysrhythmias due to local anesthetics is 20% lipid emulsion therapy - don't follow ACLS protocol as epinephrine or other antidysrhythmics (especially lidocaine) will be lethal.
