Succinylcholine

Question 1

What is the brand/trade name for succinylcholine?

Answer 1

• Anectine

_{Anesthesia Guidebook - Episode 17: Anesthesia Top Drawer Run Down - Part 1
Nagelhout (7th ed.), pp. 158 - Table 12.4, 169 - Table 12.10
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 2

BONUS

Structurally, succinylcholine is composed of two ___________ molecules joined together

Answer 2

• Acetylcholine

All neuromuscular blockers are structurally related to acetylcholine

_{Nagelhout (7th ed.), p. 156
Stoelting’s Pharmacology (5th ed.), pp. 323, 325
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 3

What is the pharmacologic category/class of succinylcholine?

Answer 3

• Depolarizing neuromuscular blocking agent

_{Nagelhout (7th ed.), p. 156
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 4

What is the mechanism of action of succinylcholine?

Answer 4

• Initial activation of nicotinic acetylcholine receptors at neuromuscular junction, followed by desensitization/antagonism

_{Anesthesia Guidebook - Episode 17: Anesthesia Top Drawer Run Down - Part 1
Nagelhout (7th ed.), p. 156
Stoelting’s Pharmacology (5th ed.), p. 325
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 5

What is the ED₉₅ dose of succinylcholine?

Answer 5

• 0.3 mg/kg

Dose that causes, on average, 95% supression of twitch height

_{Stoelting’s Pharmacology (5th ed.), p. 325
Nagelhout (7th ed.), p. 156}

Question 6

What is the typical dosing range of succinylcholine to rapidly achieve good intubating conditions?

Adult & Peds

Answer 6

• 1-1.5 mg/kg IV

Different texts list ranges as wide as 0.5-2 mg/kg, with larger doses more conducive to RSI

Intubating doses of NMBA are usually 2-3x the ED₉₅

_{Anesthesia Guidebook - Episode 17: Anesthesia Top Drawer Run Down - Part 1
Nagelhout (7th ed.), pp. 156-157, 158 - Table 12.4, 169 - Table 12.10
Stoelting’s Pharmacology (5th ed.), p. 325
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 7

What is the onset of action for succinylcholine?

Answer 7

• 30-60 seconds, or less

_{Anesthesia Guidebook - Episode 17: Anesthesia Top Drawer Run Down - Part 1
Nagelhout (7th ed.), pp. 156-157, 158 - Table 12.4, 169 - Table 12.10
Stoelting’s Pharmacology (5th ed.), p. 325
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 8

What is the duration of action for succinylcholine?

Answer 8

• 5-15 minutes — ultrashort acting

Twitch recovery at ~5 mins, 90-95% twitch recovery in ~8 mins

_{Anesthesia Guidebook - Episode 17: Anesthesia Top Drawer Run Down - Part 1
Nagelhout (7th ed.), pp. 157, 158 - Table 12.4, 169 - Table 12.10
Stoelting’s Pharmacology (5th ed.), p. 325
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 9

What organ(s) are responsible for succinylcholine’s clearance (metabolism/elimination)?

Answer 9

• Metabolism: Plasma cholinesterase
• Elimination: Kidneys

Half life: ~2-4 mins

_{Anesthesia Guidebook - Episode 17: Anesthesia Top Drawer Run Down - Part 1
Nagelhout (7th ed.), pp. 157, 169 - Table 12.10
Stoelting’s Pharmacology (5th ed.), p. 325}

Question 10

What are the potential cardiovascular effects of succinylcholine?

Answer 10

Bradycardia → asystole - mimics acetylcholine at cardiac muscarinic receptors

• More likely in children or after a repeat dose

Tachycardia - mimics acetylcholine at sympathetic ganglia

• More common in adults

_{Apex Unit 5: Pharmacology 2; Neuromuscular Blockers; Lesson 6. Succinylcholine Side Effects
Nagelhout (7th ed.), p. 158
Stoelting’s Pharmacology (5th ed.), p. 327
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 11

True or False:

Succinylcholine indirectly increases intracranial pressure (ICP)

Answer 11

• True — the clinical implications of this are still up for debate

Induction agents and/or pretreatment with nondepolarizer minimize this

_{Apex Unit 5: Pharmacology 2; Neuromuscular Blockers; Lesson 6. Succinylcholine Side Effects
Nagelhout (7th ed.), p. 157
Stoelting’s Pharmacology (5th ed.), p. 327
UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 12

An intubating dose of succinylcholine increases serum potassium levels by __________ for up to __________ minutes

Answer 12

• 0.5-1.0 mEq/L
• 10-15

_{Apex Unit 5: Pharmacology 2; Neuromuscular Blockers; Lesson 6. Succinylcholine Side Effects
Nagelhout (7th ed.), pp. 158, 161-163
Stoelting’s Pharmacology (5th ed.), p. 327}

Question 13

Succinylcholine has been associated with severe __________ in patients with burns or conditions associated with upregulation of extrajunctional acetylcholine receptors

Answer 13

• hyperkalemia

_{Nagelhout (7th ed.), pp. 161-163
Stoelting’s Pharmacology (5th ed.), p. 327}

Question 14

What is the concentration (mg/mL) of succinylcholine vials?

Answer 14

• 20 mg/mL

Vials are often 10 mL

_{UpToDate - Succinylcholine (suxamethonium): Drug Information}

Question 15

laryngospasm dose

Question 16

MH triggering agent

Question 17

IM dose