Endocrine

Question 1

Effects of hyperglycemia

Answer 1

Impaired immune response leading to inc risk of infection, impaired wound healing, dehydration, electrolyte disturbances (hyperK)

Question 2

Should an MG patient continue their pyridostigmine the morning of surgery?

Answer 2

No clear answer but continuing could help avoid resp difficulties prior to surgery.

The disadvantage however is possibility of prolonged NMB with Sux and developing cholinergic crisis.

Question 3

How would you evaluate a patient’s Carcinoid?

Answer 3

Functional vs. non-functional
- flushing, diarrhea, bronchospasm, BP swings or palpitations, murmurs

Dx = Urinary 5-HIAA

Question 4

What are your anesthetic concerns for a patient with Carcinoid?

Answer 4

1. Cardiac concerns - right sided heart lesions, heart failure
2. Pulmonary concerns - bronchospasm, dyspnea, etc
3. Avoid triggering a crisis
   - avoid meperidine, morphine, sux, atracurium, mivacurium (histamine)
   - avoid fasciculations from sux or vigorous abdominal scrubbing
   - avoid exogenous catecholamines - epi, levo, stress, anxiety, pain, hypotension, hypothermia, laryngoscopy
   - things high in serotonin/histamine - coffee, cheese, etOH,

Question 5

How would you evaluate a pheochromocytoma patient’s readiness for surgery?

Answer 5

Volume status - CBC for hemoconcentration
BP trends
SOB or chest pain
EKG - LVH, t-wave and ECHO esp w/ dec energy level (catecholamine induced cardiomyopathy)
Started and alpha 10-14 days–> beta blockers

Roizen criteria

• supine BP <160/90
• orthostatic hypotension <80/45
• EKG w/o ST, T wave changes
• no more than 1 PVC every 5 minutes

Question 6

How is a Pheo diagnosed?

Answer 6

Plasma metanephrines

Urinary catecholamines
Urinary VMA

Question 7

What drugs would you avoid in a Pheo?

Answer 7

1. Drugs that stimulate tumor cells
   - Sux from fasiculations
   - Morphine and atracurium from histamine
2. Drugs that inc sympathetic activity
   - atropine, ketamine, ephedrine
3. Drugs that sensitize myocardium to catecholamines
   - halothane, droperidol, metoclopramide, ephedrine —-> HTN

Question 8

Tx BG 356

Answer 8

? Developed DKA - any N/V, abdominal pain
10U insulin
NS fluid replacement
Urinary and serum ketones
ABG
Anion gap
Insulin gtt to dec by 75-100 per hour (avoid cerebral edema)
Add 5% dextrose at bg250
Replace potassium, mag

Even a short delay to resolve acidosis, hypovolemia and hypokalemia reduce the risk of cardiac arrthymia and hypotension

Question 9

Flow volume loop for large thyroid mass

Answer 9

Fixed obstruction - flattening of both inspiratory and expiratory limbs

Question 10

How would you optimize hyperthyroid patient for surgery?

Answer 10

Consult endocrine
Continue PTU - inhibits peripheral conversion T4->T3
Administer beta blockade (normal HR)
Glucocorticoids (dec conversion of T4)
Hydration
Normal electrolytes

Question 11

How would you differentiate between MH, thyroid storm and NMS?

Answer 11

All manifest with tachycardia, hyperthermia and AMS

MH and NMS - metabolic acidosis, profound hypercarbia, muscle rigidity
NMS usually slower development than MH
NMS flaccid paralysis with ND-NMBS
Tx immediately with dantrolene

Question 12

How would you treat thyroid storm?

Answer 12

Acetaminophen 
Active cooling
Beta blockers
Fluids
Correct electrolytes
PTU
Hydrocortisone

Question 13

Hormones produced by pituitary

Answer 13

ACTH
Prolactin
GH
TSH
FSH
LH

ADH
Oxytocin

Question 14

What are the mechanisms of bromocriptine and octreotide

Answer 14

Bromo - D2 agonist inhibits secretion of GH and prolactin

Octreotide - somatostatin analogue that dec release of GH

Question 15

Systemic manifestations of RA

Answer 15

Pericardial thickening, effusion
Valve fibrosis, ischemia, diastolic dysfunction, nodules cause dysrhythmias

Pleural effusions, pulm fibrosis
neuropathies
liver and kidney dysfunctions
Dry eyes and mouth

Question 16

Pathophysiology of myasthenia gravis

Answer 16

Antibodies or destruction of post-synaptic Ach receptors —> weakness, easy fatiguability

Ptosis, dysarthria, dysphagia, resp insufficiency, aspiration

Tx = anticholinesterase (pyridostigmine)

Question 17

Should you use sux with myasthenia gravis?

Answer 17

Can use Sux when indicated
Typically RESISTANT to sux

If on anticholinesaterase therapy, duration may be prolonged (dec plasma cholinesterase activity)

Not on therapy/undiagnosed –> profound sensitivity of ND-NMBDs

Question 18

MG patient - After getting neostigmine, resp effort improves but 45 min later complains of weakness and dyspnea. What is the cause?

Answer 18

Myasthenic crisis vs. cholinergic crisis

Give 10mg edrophonium —> improved strength, mydriasis = myasthenic

Question 19

What is Carcinoid syndrome and why doesn’t it manifest with all carcinoid tumors?

Answer 19

Complex of signs and symptoms that result when vasoactive substances are released from carcinoid tumors –> flushing, bronchoconstriction, diarrhea, right sided heart disease

Most are GI –> portal circulation and removed by liver. Syndrome develops when bypass portal system (mets to liver or outside GI tract

Question 20

How would you optimize a patient with carcinoid for surgery? Induce?

Answer 20

Diarrhea –> fluid resuscitation
Ocreotide –> dec release of vasoactive substances
Anxiolytic –> dec stress-induced release
H1, H2, steroids –> dec systemic effects of substances

Slow controlled, deep induction to avoid tumor release of vasoactive substances

Question 21

What are the signs and symptoms of thyrotoxicosis?

Answer 21

Tachycardia
Inc CO
Dec SVR, PVR
Anxiety, agitation, tremors
Weakness, sweating, heat intolerance, weight loss
Dec TSH, Inc free T3, T4

Question 22

Cholinergic crisis vs. Anticholinergic crisis

Answer 22

Cholinergic

• DUMBELS
• Organophosphates
• Tx = 2-4mg Atropine, pralidoxime

Anticholinergic

• Hot, Blind, Mad, Dry
• Atropine
• Tx = Physostigmine

Question 23

Atropine dose

Answer 23

Adults

• 0.5 - 1mg q2-3min
• Max 3mg

Peds

• 0.02mg/kg
• Min 0.1mg –> max 0.5mg
• Max 3mg total

Question 24

Flumazenil dose

Answer 24

0.2 q 15s
1mg q2min

Max 5mg

Question 25

How would you assess if a myasthenia patient is optimized for surgery?

Answer 25

I would asses for severity of her symptoms - ocular only --> respiratory, laryngeal muscles by talking , swallowing Any issues with previous anesthetics, prolonged intubations Any episodes of myasthenia crisis Stability of symptoms over past year Assess B/L motor strength in extremities and look for pharyngeal muscle involvement

Question 26

How would you induce a MG patient? Would you use NMBs? If so, which ones? How would you dose? Would you use a twitch monitor?

Answer 26

Assuming a reassuring airway I would - apply monitors - Pre O2 - slow controlled induction with short acting agents - remi, prop, lidocaine I would avoid NMBs if possible because they are highly sensitive to ND-NMBDs. I would use very small dose and titrate or SUX 1.5-2mg/kg due to resistance to sux I would use a twitch monitor recognizing that may not be reliable. Weakness is uneven and may exhibit fade baseline

Question 27

What is myasthenic crisis and what are the precipitating factors?

Answer 27

Severe bulbar or respiratory symptoms from progression of disease or other factors. - infection - surgery - stress - hypothermia - acidosis - hypoK - hypoMag - aminoglycosides - flouroquinlones - clindamycin - BBs - CCBs - NMBDs - Anticholinergics

Question 28

Post-op from Pheo resection patients BG is 35. What would you do?

Answer 28

Recheck quickly to confirm Start D5 infusion Verify hemodynamically and neurologically stable Surge of insulin sensitivity following low serum catecholamine levels

Question 29

How would you address hypothyroidism pre-operatively?

Answer 29

Ideally delay until euthyroid ``` Inc aspiration risk Inc sensitivity to opioids Hypoglycemia Hypotension Adrenal insufficiency Delayed emergence ```

Question 30

MG patient with fever pre-op, is this a concern? Would you give anti-pyretics?

Answer 30

Yes, this could be indicative of a myasthenia crisis or an infection like PNA or C.diff (common in MG). Therefore I would order blood, sputum or stool cultures based on any other symptoms or perform a Tension test to rule out myasthenia crisis. I would give anti-pyretics because fever can induce a MG crisis. I would verify any antibiotics are not know to cause MG crisis before administering.