In this episode I’ll
1. Discuss some cases of using IV lipid emulsion for drug toxicity
2. List which patient care areas in my institution are stocked with IV lipid emulsion
3. Review the dosing of IV lipid emulsion
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I first heard of the idea of using IV lipid emulsion as an antidote to drug overdose in 2008. An emergency physician showed me an article discussing a case that was reported in Annals of Emergency Medicine.
A 17 year old female ingested nearly 8 grams buproprion and 4 grams lamotrigine in a suicide attempt. She developed seizure and cardiovascular collapse. She was coded for 70 minutes, until an anesthesiologist suggested giving IV lipid emulsion. Within 1 minute of receiving lipid emulsion, the patient had return of spontaneous circulation (ROSC). She recovered with near-normal neurologic function.
The case presented a compelling temporal relationship between the administration of IV lipids and ROSC. Previous to this case, lipid emulsion had only been used as an antidote for local anesthetic systemic toxicity (LAST).
The first research using lipids to treat LAST was published in 1998 with a rat model of bupivicaine toxicity and the first published human case report of lipid emulsion to treat LAST was in 2006.
A 58 year old male had a cardiac arrest after placement of an interscalene block with bupivacaine and mepivacaine. After 20 minutes of advanced cardiac life support his rhythm had progressed to vtach, vfib, and asystole. He was given IV lipid emulsion and within 15 seconds had ROSC.
After reading the above cases, I took steps at my hospital to make sure that IV lipid emulsion was available in all critical care and peri-operative PYXIS machines.
Several uneventful years went by and wouldn’t you know it, on my day off a patient coded in our pre-op area 40 minutes after a ropivicaine block was placed. He had a very long code with many shocks and amiodarone administrations. Utimately, IV lipid emulsion was administered. Within 1 minute the patient had ROSC. He was eventually discharged home neurologically intact. The only adverse event from the lipid emulsion that was noted was his blood draws looked like strawberry milkshakes for 24 hours.
It was very satisfying to know that our hospital was prepared to respond to this type of crisis. On the other hand, I did have that thought of “Oh sure, the fun stuff only happens on my day off”.
It is such a tempting mindset to take – hoping that you get to be involved in a “great save”. But for such an opportunity to present itself, that means something bad must first happen to a patient.
The late Dr. John Hinds discussed this attitude in a talk he did on resuscitative thoracotomy. Skip forward to 16:00 to hear him talk about this.
So as exciting as it is to successfully provide for the pharmacotherapy needs of a crashing patient, I always keep John’s words in mind. His words temper the attitude of “I wish I got to do that” that I sometimes feel when I hear about someone else’s “great save”.
Now that some additional data has been published on the use of IV lipids as a treatment in cardiac arrest from drug toxicity, The 2015 CPR Guidelines Update contains a new recommendation that IV lipid emulsion may be considered in patients with cardiac arrest due to drug toxicity other than LAST who are failing standard resuscitative measures. I discussed these changes back in episode 26.
A complete review titled Lipid emulsion infusion: resuscitation for local anesthetic and other drug overdose was published by Guy Weinburg in the journal Anesthesiology in 2012. Dr. Weinburg maintains the website lipidrescue.org which is a fantastic resource on the topic.
The full text of his article is free and I highly suggest that you read the article in its entirety. The article discusses the possible mechanisms of action for IV lipid emulsion as an antidote (as a lipid sink and other possibilities), as well as reviews published cases and controversies in IV lipid emulsion use.
IV lipid emulsion may work for any lipophilic drug toxicity. There are even case reports of patients with synthetic cannabinoid intoxication that have responded to IV lipid emulsion!
The ideal dose of IV lipid emulsion for drug toxicity is probably not known, so I follow the dose used for LAST published by The American Society of Regional Anesthesia and Pain Medicine.
Using Lipid Emulsion (20%) give a bolus 1.5 mL/kg (lean body mass) intravenously over 1 minute.
Start a continuous infusion 0.25 mL/kg/min.
Repeat the bolus once or twice for persistent cardiovascular collapse.
Increase the infusion rate to 0.5 mL/kg/min if the patient’s blood pressure remains low.
Continue the lipid infusion for at least 10 minutes after attaining circulatory stability.
Recently on twitter I was discussing IV lipid emulsion therapy with an anesthesiologist. He had used it successfully in a patient but it took a while for him to obtain the IV lipid emulsion during the code.
I encourage you to check on the location of IV lipid emulsion throughout your hospital & take the time to make sure it is readily available in any patient care areas that might encounter LAST or drug overdose toxicity.
Have you used IV lipid emulsion therapy in a patient with drug overdose? I’d love to hear how it went! Send me an email firstname.lastname@example.org.
Update: Thank you to reddit user hojoseph99 and Pharmacy Nation member “Pharmacy Kyle” for pointing out some practical tips for lipid administration! Kyle says:
My practical advice is:
a) Remember all these ml/kg doses are for 20% lipid.
b) Store a couple 60ml syringes with it for the bolus (unless those are easy to find in your hospital).
c) If your pumps top out at 999ml/hr, that’s the maintenance infusion for a 65kg patient. If you’re struggling with the math in the heat of the moment, just start the pump at 999 while you figure it out.
d) For LAST that turns pulseless , the ASRA recommends reducing epinephrine to the hypotension-push dose (up to 1mcg/kg at a time) rather than the potentially detrimental whole milligram.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.