Difficulties implementing the guidelines for the management of severe local anaesthetic toxicity

The Association of Anaesthetists of Great Britain and Ireland (AAGBI) guidelines for the management of severe local anaesthetic toxicity [1] suggest an infusion of 0.25 ml.kg.min after the initial bolus of Intralipid 20%. The infusion should be doubled to 0.5 ml.kg.min after 15 min if an adequate circulation has not been restored. In an 80-kg patient, this requires an initial rate of 1200 ml.h, increasing to 2400 ml.h after 15 min. Volumetric infusion devices in our hospital wards are only capable of delivering rates of up to 999 ml.h. The syringe pumps in our intensive care unit can only deliver up to 200 ml.h, while those in theatres can deliver up to 1200 ml.h. We contacted representatives of infusion device suppliers in the United Kingdom. Of the five manufacturers we contacted, the maximum volumetric device infusion rate we found was 1200 ml.h, enough to resuscitate only a 40-kg patient at the higher infusion rate. One syringe pump could achieve 1800 ml.h but would require eight syringe changes to reach the volume required for an 80-kg patient. In addition, in the heat of a cardiac arrest situation we should bear in mind that large volume infusions are rarely set up at precise rates via syringe pumps or infusion devices. Instead, these volumes are often allowed to run-in through a wide-bore open giving set. An alternative would be to have a single protocol for all adults which could be used independent of weight. As there are varying recommendations on the initial bolus dose, an exact dose and infusion rate based on the patient’s weight may not be required. Whereas the AAGBI guidelines state 1.5 ml.kg, Weinberg [2] recommended a dose of 1 ml.kg and a recent case reported a successful outcome using an initial bolus of 3 ml.kg [3]. With wide variation in recommendations for the bolus dose and practical difficulty adhering to precise infusion rates, we would suggest a simpler protocol for all adults. Time 0: Bolus 100 ml Intralipid 20%. Infuse remainder of 500-ml bag (400 ml) over approximately 20 min. 5 min: Bolus 100 ml (from 2nd bag of Intralipid ). 10 min: Bolus 100 ml (from 2nd bag of Intralipid ). Once the first 500-ml bag has finished, infuse remaining 300 ml of the second bag over approximately 10 min. This protocol may be altered for the extremities of weight, but would still provide a simple model for Intralipid use in adult resuscitation.