Local Anesthetic Toxicity
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Transcript Local Anesthetic Toxicity
Local Anesthetic
Toxicity
Chuck Magich, MS, CRNA
Staff Nurse Anesthetist
R Adams Cowley, Shock Trauma Center
Baltimore, MD
October 2013
Used in epidural
catheters & peripheral
nerve block catheters.
“caine” family:
Lidocaine
Bupivicaine
Physiology
Local anesthetics block Na+
channels to prevent impulse
transmission.
Meant for perineuronal
injection, not IV!
Can bind to other receptors,
especially cardiac.
More about Locals
• Bolus at insertion 20-40 cc’s
• Infusion rates 5-10cc’s /hr
• Epi used in local to detect intravascular
injection (HTN, tachy)
• Epi also used to prolong duration of
action by causing vasoconstriction to
area infiltrated
• Always aspirate before injecting
• Small incremental injections
Signs & symptoms of toxicity
CNS
Dizziness
Circumoral numbness
Tinnitus
Metallic taste
Confusion
Seizure
Coma
Cardiovacular
Hypotension
Bradycardia
Heart Block
Vent Arrythmias
V-tach
V-Fib
Asystole
Traditional Management of Toxicity
BLS
ACLS
CPB
Often prolonged
resus w/poor
outcomes
History of Lipid Rescue
First discovered in 1998 by Weinberg
First used to successfully treat patient in 2006
(Rosenblatt)
Now being shown to be effective for other types of
OD’s: TCA’s, beta blockers, calcium channel blockers
Rat Experiment
http://youtu.be/b70Li9r3pL8
http://youtu.be/B3au3aKU4oE
Lipid Rescue Protocol
Calculations
70 Kg patient:
1. Bolus dose?
2. Infusion rate (cc/hr)?
105 cc’s IV push
1050 cc/hr
“Rule of 15:”
Bolus = 1.5
0.25ml/kg/min = 15 X wt(kg) = cc/hr
Notify pharmacy ASAP!
How it works
“Partitioning”:
• Lipid Sink
• Lipid Pool
• Lipid Sponge
Location
Currently in large omnicell just outside New TOR entrance
Available at all satellite
pharmacy windows:
• GOR
• 3rd floor old trauma
building
Hospital-wide date TBA
Once hospital wide, only in key omnicells, not every one.
Contents:
1. 20% Intralipid (500ml)
2. A l a r i s p u m p t u b i n g
3. C o p y o f p r o t o c o l
Case Study
• 84 y/o, ASA 2, 70 kg
• Femoral neck fx
• Block w/ 30cc 0.25%
Bupivicaine
• Neg asp after every 5 cc
• c/o feeling “funny” 1 min
after block
• Became unresponsive
followed by seizure
• Developed PEA arrest
• Intubated & CPR started
• 1mg epi given
• 20% intralipid started
within 5-8 mins after LOC
• Rec’d 500 ml lipid total
• Soon after lipid started
developed SB 35
• Atropine 0.5mg x 2
• Ext pacing started
• HR 70 w/stable BP
• To ICU on no pressors
• 24* later hemiarthroplasty
performed
• Extubated end of case
• DC to floor 3 days later
• Completely neurologically
intact
Need to Know More???
Websites:
1. http://lipidrescue.org
2. http://www.lipidrescue.com
References
1. http://lipidrescue.org
2. http://www.lipidrescue.com
3. Weinberg, GL (2012). Lipid Emulsion Infusion: Resuscitation
for Local Anesthetic and Other Drug Overdose.
Anesthesiology 2012; 117 (1), pp. 180-187.
4. Hiller, DB; Gregorio, GD; Ripper, R; Kelly, K; Massad, M;
Edelman, L; Edelman, G; Feinstein, DL; Weinberg, GL.
Epinephrine Impairs Lipid Resuscitation from Bupivacaine
Overdose: A Threshold Effect. Anesthesiology 2009: 111
(3), pp.498-505.