Mashman: MH

Question 1

What can occur with abnormal handling of intracellular calcium in skeletal muscle?

Answer 1

malignant hyperthermia

Question 2

What are the triggering agents of malignant hyperthermia?

Answer 2

succinylcholine

volatile agents (except nitrous oxide!)

very rarely, extreme exercise and environment

Question 3

What receptors are affected in MH? (2)

Answer 3

ryanodine (RYR 1) receptor

DHP (dihydropyridine) receptor

Question 4

What will you acutely observe with MH?

Answer 4

HYPERKALEMIA

Increase in K will be dramatic.

Note: in patient you will observe dark veins and it is NOT due to cyanosis!

Question 5

What clinical sign will you observe in MH patient? (4)

Answer 5

increased CO2 production!

masseter muscle rigidity

rhabdomyolysis (muscle breakdown)

increased temperature much later

Question 6

MH may occur at any point during anesthesia or in emergence. True or false?

Answer 6

true.

Question 7

What enzyme is strongly associated with MH susceptibility (80%)?

Answer 7

serum CPK

(creatine phosphokinase)

Question 8

What are the early indications of MH? (6)

Answer 8

• increased CO2 production
• increased HR and dysrhythmias
• Resp/Met acidosis
• venous desaturation
• Electrolyte abnormality
• MMR

Question 9

What changes will be observed in EKG with MH? (2)

Answer 9

peaked t-waves

wide QRS

Question 10

Diseases definitely associated with MH: (4)

Answer 10

Central Core Disease
King-Denborough Syndrome
Hypokalemic periodic paralysis
Multiminicore Disease

Question 11

Diseases possibly associated with MH: (3)

Answer 11

exertional heat stroke

exercise induced rhabdomyolysis

Duchenne muscular dystrophy

Question 12

Children less than 9 years of age, who experience a sudden cardiac arrest after succinylcholine, in the absence of hypoxemia, should be treated for acute hyperkalemia first. True or false?

Answer 12

true

Question 13

What do you do if you have a patient having indications of MH? (5)

Answer 13

• Have a response plan in place
• STOP all volatile agents
• Call for help
• HYPERVENTILATE WITH 100% O2 > 10L/min
• Give dantrolene

Question 14

Acute Phase Therapy for patient with MH:

What should you be doing after giving dantrolene?

Answer 14

• Treat arrythmias
• Treat hyperthermia, endpoint is 38ºC
• Frequent blood gases
• Serum CK
• Keep urine output > 2cc/kg/hr
• Consider analgesia and amnesia

Question 15

How do prepare for a patient with MH with respect to the anesthesia machine? (4)

Answer 15

• New fresh gas outlet hose and circle system tubing
• remove vaporizers
• flush system with >10L/min O2 for 10 minutes, flush for 20 minutes if fresh gas outlet hose cannot be replaced
• MH cart is in or near OR

Question 16

Worse outcome of MH is associated with patients with: (2)

Answer 16

muscular build

presence of DIC (disseminated intravascular coagulation) problem like pregnant women or sepsis

Question 17

Lessons of MH: (4)

Answer 17

• Education of MH awareness and early detection
• Dantrolene and MH cart availability
• A response plan that is known to work
• Transfer of care plan in place