American Society of Regional Anesthesia and Pain Medicine February 2018 - 39

treatment for LAST, and 20 individuals (50%) acknowledged
knowing how and where to find it in the perioperative environment.
All of these deficiencies highlighted the potential challenges in
managing LAST in ASCs.

Figure 1: ASRA checklist located with local anesthetic supplies.

Considering the benefit of using simulation to improve response
to rare events,8 perioperative staff members were taken through a
low-fidelity, low-intensity simulation of diagnosing and caring for a
suspected case of LAST. Special focus was given to the significance of
lipid emulsion as the mainstay of treatment as well as standardization
of the process for securing the lipid emulsion at the bedside and
the process for initiating patient transfer with the potential need
for cardiopulmonary bypass. During the event, we highlighted the
now-standard placement of the ASRA checklist, located with our local
anesthetic supplies (Figure 1). After the simulation, participants were
surveyed again about the treatment of a patient with presumed LAST,
and all individuals (100%) responded with confidence.
In response to the simulation session, an important question was
raised: How much lipid emulsion should we have available to be
adequately prepared to appropriately treat a patient while awaiting
transfer? Following the ASRA checklist recommendations, patients
experiencing LAST should receive a 1.5-mL/kg lean body mass
bolus of lipid emulsion equating to approximately 100 mL of lipid
emulsion for a 70-kg patient. Subsequently, the patient should
receive a 0.25-mL/kg/min infusion dose, which equates to an
approximate rate of 18 mL/min. In addition, the LAST checklist
suggests repeating bolus doses or doubling the infusion rate for
persistent cardiovascular instability. With these recommendations,
it is easy to anticipate the need of more than 1,000 mL of lipid
emulsion while awaiting transfer to a tertiary care center. Even
with two 250-mL bags available, our previous standard, the lipid
emulsion infusion would be sufficient to treat a patient for only
approximately 25 minutes. At the recommended doses, combined
with the frequency with which we care for obese patients (who
have an increase in lean body mass in addition to excess fat9), a
relatively large amount of lipid emulsion must be available at freestanding ASCs, because a patient may be delayed more than 1 hour
before reaching a more equipped medical facility with expanded
pharmaceutical service. We believe that this is true for many ASCs
and could potentially limit the safety of patient care.
LAST is a rare complication of which regional anesthesia providers
are keenly aware, but in today's ever-changing workplace,
successful management of any complication, especially one
as potentially devastating as LAST, requires that support staff
are educated on early recognition and initial management and
that work environments are designed with safety in mind and
adequately supplied to ensure optimal outcomes. As the number of
regional anesthetics continues to rise, particularly in ASCs, we must
strive for excellence in our preparedness, otherwise our practice
and patients face the ultimate adverse consequence.

REFERENCES
1.

Liu SS, Ortolan S, Sandoval MV, et al. Cardiac arrest and seizures due to local
anesthetic systemic toxicity after peripheral nerve blocks: should we still fear
the reaper? Reg Anesth Pain Med 2016;41:5-21.

Barrington MJ, Kluger R. Ultrasound guidance reduces the risk of local
anesthetic systemic toxicity following peripheral nerve blockade. Reg Anesth
Pain Med 2013;38:289-297.

Di Gregorio G, Neal JM, Rosenquist RW, Weinberg GL. Clinical presentation of
local anesthetic systemic toxicity: a review of published cases, 1979 to 2009.
Reg Anesth Pain Med 2010;35:181-187.

Vasques F, Behr AU, Weinberg GL, Ori C, Di Gregorio G. A review of
local anesthetic systemic toxicity cases since publication of the ASRA
recommendations: to whom it may concern. Reg Anesth Pain Med
2015;40:698-705.

Neal JM, Weinberg GL, Bernards CM, et al. ASRA practice advisory on local
anesthetic systemic toxicity. Reg Anesth Pain Med 2010;35:152-161.

Collins J. Awareness of local anaesthetic toxicity issues among hospital staff.
Anaesthesia 2010;65:960-961.

Goldfarb CA, Bansal A, Brophy, RH. Ambulatory surgical centers: a review of
complications and adverse events. J Am Acad Orthop Surg 2017;25:12-22.

Neal JM, Hsiung RL, Mulroy MF, Halpern BB, Dragnich AD, Slee AE. ASRA
checklist improves trainee performance during a simulated episode of local
anesthetic systemic toxicity. Reg Anesth Pain Med 2012;37:8-15.

Forbes GB, Welle SL. Lean body mass in obesity. Int J Obes 1983;7(2):99-107.

American Society of Regional Anesthesia and Pain Medicine
2018

Table of Contents for the Digital Edition of American Society of Regional Anesthesia and Pain Medicine February 2018