The reason: If your center uses MH triggering agents — the volatile
general anesthetics halothane, enflurane, isoflurane, desflurane and
sevoflurane, and the muscle relaxant succinylcholine — you need
enough dantrolene to provide an initial loading dose of 2.5mg/kg
(250 mg if the patient weighs 100 kg). However, the initial 2.5mg/kg
dose would not be sufficient to treat larger patients (100-plus kg),
who require 1,000 mg to 2,000 mg of dantrolene to deliver the
10mg/kg to 20 mg/kg dose needed for stabilization. Answer "c" is
acceptable for outpatient centers close to an affiliated tertiary care
medical center with more dantrolene immediately available. But
most standalone facilities, especially those in remote locations,
should have immediate access to 2,000 mg
of dantrolene.
2. Which cooled IV fluid should be available on your MH cart?
a. normal saline solution
b. half-normal saline solution
c. Ringer's lactate
d. dextrose 5% in water
Answer: a
The reason: Cooled saline should be available for immediate infusion
in age/size appropriate quantities for management of a patient's rapid-
ly rising body temperature. IV volume expansion is also critical in the
management of MH, so that a solute diuresis will maintain urine flow
and reduce the risk of myoglobinuric renal failure following muscle
damage. That's why MHAUS does not recommend the use of fluids
such as half-normal saline, dextrose 5% in water and dextrose 5% half
or quarter in normal saline to help cool a patient, because they are
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