Local Anesthetics
Recent recs from the anesthesia world
Intralipids
lipidrescue.com
Data from humans are limited to two case reports (see News) and no prospective epidemiologic study is possible since numbers are too small; and ethical considerations rule out experiments on volunteers. So these data are very limited as well. Both patients received bolus injections of 100 mL 20% Intralipid followed by continuous infusions at either 0.5 mL/kg/min for 2 hours, or 10 mL/min for 10 minutes. In both cases, the same general approach was used as in the animal experiments, namely a bolus followed by a continuous infusion.
Given an understanding of these limitations in our method an Example Protocol follows; this should be used only after standard resuscitation methods fail to re-establish sufficient circulatory stability:
20% Intralipid:
1.5 mL/kg as an initial bolus, followed by
0.25 mL/kg/min for 30-60 minutes
Bolus could be repeated 1-2 times for persistent asystole
Infusion rate could be increased if the BP declines.
See the Instructions link in the Navigator to find sample protocols for LipidRescue as Word files that you can print and laminate . These could then be attached to lipid emulsion bags stored for this purpose near your block rooms.
Intralipid
® for Overdoses
Intralipid
® (lipid emulsion) is intravenous fat emulsion used to supplement parenteral nutrition, but has been
studied as a possible salvaging therapy for certain overdoses. Intralipid
® is composed of triglycerides, phospholipids
and choline. Intralipid
® forms chylomicron-like droplets in the serum that may act as a sink for
lipid soluble toxins. The toxins distribute into the chylomicrons, away from binding sites and target organs of
toxicity. Intralipid
® may also modulate cardiac energy and improve calcium channel functioning, but these
effects are felt to be minor.
Intralipid
® use has been studied in animal models of bupivicaine, verapamil, clomipramine and propranolol
cardiotoxicity. Human case reports of successful use of Intralipid
® for bupivacaine, ropivacaine and bupropion
induced cardiac arrest are published. It is important to remember that current human data are limited
on this experience. At this point, Intralipid
® is only indicated if the patient suffers from a cardiac arrest
from an exposure to the following:
Intralipid
® 20% is given as an intravenous bolus in a dose of 1.5 mL/kg over 1 min. The bolus may be repeated
one time if the patient remains in cardiac arrest. This is followed by 15 mL/kg/hr over 30-60 minutes.
Intralipid
® can also be administered peripherally. Potential complications with Intralipid® are fat embolization,
interactions with other medications (such as vasopressors) leading to decreased efficacy, and
allergic reactions (egg-derived). (Maryland Tox Center)