UMEM Educational Pearls

Despite initial excitement for the use of intravenous lipid emulsion (ILE) therapy as an antidote for serious poisonings due to lipohphilic drugs there remains an absence of evidence combined with an incomplete understanding of its efficacy, mechanisms of action, safety, and analytical interferences to recommend its use except in a few clinical scenarios.

The lipid emulsion workgroup performed a comprehensive analysis of four systematic reviews and based recommendations from consensus of expert panelists from the American Academy of Clinical Toxicology, the European Association of Poison Centres and Clinical Toxicologists, the American College of Medical Toxicology, the Asia Pacific Association of Medical Toxicology, the American Association of Poison Control Centers, and the Canadian Association of Poison Control Centers. Toxins evaluated had to have a minimum of three human cases reported in the literature.They concluded that ILE could be indicated for the following clinical situations:

•  In Bupivacaine poisoning resulting in cardiac arrest or life threatening toxicity (dysrhythmias, VTach  with compromised organ perfusion, VFib, status epilepticus, and/or hypotension with organ compromise defined as  increased lactate concentration, acute kidney injury, increased troponin, altered mental status, or decreased capillary refill) ILE is recommended after standard ACLS is started  and if other therapies fail or as last resort.

• In life-threatening toxicity due to other local anesthetics,  ILE recommended if other therapies fail/in last resort

• In cardiac arrest due to toxicity from Amitriptyline (or other tricyclic antidepressants), lipid soluble and non-lipid soluble Beta-receptor antagonists,  Bupropion, Calcium channel blockers (diltiazem, verapamil and dfihydropyridines), Cocaine, Diphenhydramine, Lamotrigine,  Baclofen, Ivermectin and other Insecticides, Malathion and other Pesticides, Olanzapine and other Antipsychotics, and SSRIs.

• Most common regimen of ILE was a bolus of 1.5 mL/kg of ILE 20% followed by infusion of 0.25 mL/kg/min

• The use of ILE with extracorpeal membrane oxygenation may cause fat deposition in the circuit and increase blood clot formation causing malfunction and limitation of use of this potentially life saving modality. This should be considered if VA-ECMO is a treatment option.

 

The Bottom Line:

The use of Intravenous Lipid Emulsion in severe poisoning is recommended only for a few poisoning scenarios and was based on very low quality of evidence, and consideration of risks and benefits, adverse effects, laboratory interferences as well as related costs and resources.

References