Sympathetic Nervous System

Question 1

Peripheral collection of nerve cell bodies

Answer 1

Ganglion

Question 2

Number of paired sympathetic ganglia

Answer 2

22

Question 3

SNS preganglionic pathway to sympathetic chain

Answer 3

Myelinated B fibers exit spinal cord via ventral nerve roots > white communicating rami > sympathetic chain

Question 4

Preganglionic sympathetic axons (C fibers) that traverse uninterrupted through the sympathetic trunk form____

Answer 4

Splanchnic nerves

Question 5

Collection of plexuses that surrounds the abdominal aorta

Answer 5

Abdominal prevertebral plexus

Question 6

Abdominal prevertebral plexuses

Answer 6

Celiac plexus
Aortic plexus
Superior hypogastric plexus
Inferior hypogastric plexus (pelvic)

Question 7

Location of cell bodies of preganglionic sympathetic fibers

Answer 7

Interomediolateral horn of the spinal cord (Rexed’s lamina 7)

Question 8

Inferior cervical ganglion + T1 ganglion

Answer 8

Stellate (cervicothoracic) ganglion

Question 9

SNS innervation of the stellate ganglion

Answer 9

Ipsilateral head, neck, and upper extremity

Question 10

Indications for blocking stellate ganglion

Answer 10

Treatment of:
Upper extremity sympathetic dystrophy
Complex regional pain syndrome
Increase blood flow to the upper extremity
Provide relief from intractable post-MI pain

Question 11

Horner’s syndrome symptoms

Answer 11

Ipsilateral ptosis, miosis, anhidrosis, flushed skin, nasal congestion, and enopthalmos

Question 12

Alternate name for adrenal glands

Answer 12

Surarenal glands

Question 13

Two divisions of adrenal glands

Answer 13

Medulla
Cortex

Question 14

Adrenal medulla function

Answer 14

Secretes catecholamines

Question 15

Adrenal cortex function

Answer 15

Secretes glucocorticoids, mineralcorticoids, and androgens

Question 16

Autonomic innervation of adrenal glands

Answer 16

Preganglionic sympathetic nerves T5-T9

No postganglionic nerves

Question 17

Mechanism of adrenal stimulation

Answer 17

Preganglionic fibers release ACh onto chromaffin cells > NnACh receptor stimulaiton > chromaffin cells release epinephrine and norepinephrine directly into circulation

Question 18

Rate/ ratio of catecholamine release from adrenal medulla at rest

Answer 18

Epi: 0.2mcg/ kg/ min (80%)
NE: 0.05mcg/ kg/ min (20%)

Question 19

Catecholamine- secreting tumor usually arising from the adrenal gland or extra chromaffin tissue

Answer 19

Pheochromocytoma

Question 20

Pheochromocytoma triad of symptoms

Answer 20

Headache
Diaphoresis
Tachycardia

Question 21

Pheochromocytoma diagnostic

Answer 21

Elevated level of VMA

Question 22

Pheochromocytoma preoperative treatment

Answer 22

Alpha blockade THEN beta blockade

Question 23

Non-selective alpha blockers

Answer 23

Phenoxybenzamine
Phentolamine

Question 24

Alpha-1 selective blockers

Answer 24

Doxazosin
Prazosin

Question 25

What happens if beta is blocked before alpha in the presence of pheochromocytoma?

Answer 25

Heart failure

Question 26

Anesthetic considerations for pheochromocytoma removal surgery prior to tumor ligation

Answer 26

Treat hypertension Treat tachycardia Monitor serum glucose throughout (anticipate hyperglycemia)

Question 27

Intraoperative/ preoperative treatments for htn in patients undergoing pheochromocytoma removal surgery

Answer 27

Sodium nitroprusside nitroglycerine Clevidipine Nicardipine Deepening anesthetic

Question 28

Intraoperative/ preoperative treatments for tachycardia in patients undergoing pheochromocytoma removal surgery

Answer 28

Short-acting beta blockers like esmolol (caution with cardiomyopathy)

Question 29

Intraoperative/ preoperative considerations following removal of a pheochromocytoma

Answer 29

Hypotension = tx with phenylephrine, NE, vasopressin, or IVF Consider steroid supplementation if both adrenal glands were removed or manipulated during surgery

Question 30

Drugs to avoid in pheochromocytoma removal surgery

Answer 30

Histamine- releasing drugs (succinylcholine, atracurium, mivacurium, morphine) Indirect-acting sympathomimetic agents SNS activators: desflurane, ketamine, pancuronium, naloxone

Question 31

SNS activation effects on serum glucose and potassium

Answer 31

Stimulates hepatocytes to release more glucose and potassium

Question 32

SNS activation effects on insulin

Answer 32

Stimulates pancreatic beta cells to increase insulin output

Question 33

Two phases to K+ response to SNS stimulation

Answer 33

Initial rise (short-lived) Longer term effect is decreased K+

Question 34

Why does K+ decrease with SNS stimulation

Answer 34

Adrenal medulla secretes catecholamines > epi binds to beta-2 receptors on skeletal muscle and erythrocytes = Na+/K+ pump activation = decrease in K+ concentration

Question 35

Factors that impact serum K+ concentration

Answer 35

Beta-2 agonism (Epi, albuterol) Methylxanthines (Theophylline) Nicotinic type-M agonism (succinylcholine) Destruction of cell membranes (rhabdomyolysis) Activating H+/K+ exchanger (acidosis) Hyperventilation (alkalosis) Activating the Na+/ K+ exchanger (Epi, insulin)