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Flashcards in Endocrine Emergencies 2 Deck (42):
1

Adrenal Medulla

1. Controlled by?

2. When stimulated it secretes?

2 Adrenal Cortex

1. Three zones: What are they?

2. What do they secrete?

Adrenal Medulla

1. Controlled by nervous system

2. When stimulated secretes epinephrine and norepinephrine into adrenal veins

Adrenal Cortex

1. Glomerulosa: mineralocorticoids… aldosterone

2. Fasciculata: glucocorticoids… cortisol

3. Reticularis: sex hormones

2

Adrenocorticotropic Hormone ACTH

What does it do?

Primarily what?

Remember, -tropin or -tropic means to stimulate.

Therefore, adrenocorticotropic means “to stimulate the adrenal cortex”

Function: Stimulates synthesis and secretion of adrenocortical hormones (cortisol, androgens, and aldosterone)

ACTH primarily stimulates cortisol

3

Describe the normal ACTH physiology

 

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4

What does cortisol stimulate? 4

1) Gluconeogenesis

2) Protein mobilization

3) Fat mobilization

4) Stabilizes lysosomes

 

5

Adrenal Insufficiency vs Crisis

1. Adrenal Insufficiency is what?

2. What kind of disease is this?

3. Adrenal Crisis is what?

4. What kind of condition is this?

Adrenal Insufficiency

1. Failure of adrenal glands to produce essential BASAL secretion of steroids

2. Insidious wasting disease

Adrenal Crisis

3. Failure to RESPOND to the increased demands caused by stress or SUDDEN INABILITY to secrete essential steroids

4. Life-threatening condition

6

Nova’s likely diagnosis:

Adrenal insufficiency, of which there are two forms:?

1. Primary adrenal insufficiency (Addison’s disease)

 

2. Secondary adrenal insufficiency

 

7

Adrenal insufficiency?

1. Primary adrenal insufficiency (Addison’s disease) results from?

2. Secondary adrenal insufficiency results from?

Primary adrenal insufficiency (Addison’s disease)

1. Results from destruction or dysfunction of the adrenal cortex

Secondary adrenal insufficiency

2. Results from inadequate stimulation of adrenal cortex by ACTH (***By far the most common cause is chronic administration of exogenous steroids!)

8

Describe how the adrenal pathway changes in primary adrenal insufficiency?

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9

What would happen to the adrenal pathway with exogenous administration of corticosteriods?

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10

Decreased blood pressure?

Decreased cortisol:

1. Cortisol up-regulates alpha1-adrenergic receptors on vascular smooth muscle (what does stimulation of the alpha1 receptors do again?) so a decreased amount would…? 3

Decreased aldosterone:

2. Aldosterone increases Na reabsorption by renal cells, leading to increases in extracellular fluid volume and blood volume, venous return, cardiac output, and arterial pressure.  Therefore a decrease in aldosterone would…? 2

1.

-Cause vasodilation and

-decrease in peripheral vascular resistance

-and decreased BP

2.

-More NA+ to be excreted in the urine and also more water excretion.  

-decreased blood pressure

11

Adrenal Insuffieciency

Pulse rate increase?

Compensatory mechanisms as a result of:  4

1. Decreased volume

2. With decreased volume we have decreased arterial pressure

3. ➔ baroreceptor reflex

4. ➔ increased sympathetic outflow and therefore an increase in heart rate

12

Decreased blood glucose?

Decreased cortisol:

One action of cortisol is to increase blood glucose concentration by promoting gluconeogenesis and decreasing glucose uptake by the tissues and therefore a decrease in cortisol would…?

Decrease blood glucose levels

13

Hyperkalemia?

Decreased aldosterone:

In addition to stimulating Na reabsorption, aldosterone stimulates K secretion by the renal principal cells and therefore a decrease in aldosterone would…?

inhibit K secretion

14

Late Distal Tubule/Collecting Duct Area

1. The principal cells reabsorb what? 2 And secrete what?

2. Aldosterone exerts its effects by increasing the function of the what?

 

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15

Hyponatremia?

Decreased aldosterone

Aldosterone increases Na reabsorption by renal principal cells.  Therefore, with decreased aldosterone we would have…?

Increased Na and water excretion

16

In contrast to indolent and progressive course of chronic adrenal insufficiency, ***adrenal crisis presents as a life-threatening emergency in which the primary manifestation is what??

hypotension

17

1. When you have a patient that presents with what always consider an adrenal crisis if there is not an immediately apparent  cause?

 

2. ***The hypotension in adrenal crisis typically is

resistant to what? 2

 

3. If the missing _______ is not replaced, death will ensue!

 

1. severe hypotension

2. catecholamine and IV fluid administration!

3. cortisol

18

Adrenal Crisis 

Where is it seen? 4

1. In a previously undiagnosed patient with primary adrenal insufficiency who has been subjected to serious infection or other acute, major stress.

2. In a patient with known primary adrenal insufficiency who does not take more glucocorticoid during an acute infection (can occur during acute viral infections such as influenza) or other major illness, or has persistent vomiting caused by viral gastroenteritis or other gastrointestinal disorders.

3. After bilateral adrenal infarction or bilateral adrenal hemorrhage.

4. Rarely in patients with secondary adrenal insufficiency, can be seen in patients withdrawn abruptly from suppressive doses of corticosteroids

19

Adrenal Crisis

1. Presentation? 2

2. Dx? 4

3. Tx? 2

1. Presentation

-Marked hypotension

-Abdominal and flank pain

2. Diagnosis

-Clinically oriented for abrupt withdrawal from exogenous steroids

-For primary adrenal insufficiency, a short cosyntropin test

(Cosyntropin [ACTH analogue] injected,

-plasma cortisol levels measured in 60 minutes,

-primary adrenal insufficiency excluded if poststimulation level > 550 nmol/L)

3. Treatment

-If adrenal crisis suspected or diagnosed, IV glucocorticoids

-D5NS may be required to correct hypovolemia and hypoglycemia

20

Pheochromocytoma

1. What is it?

2. The tumor releases what?

3. which causes? 5

4. reversible?

5. Where is the tumor located the majority of the time?

1. A tumor derived from neural crest cells of the sympathetic nervous system that is responsible for about 0.1-2% of all cases of hypertension.

2.  The tumor releases catecholamines

3. Which cause episodic (this way most of the time) or sustained signs and symptoms, such as

-palpitations,

-sweating,

-headaches,

-fainting spells, and

-hypertensive emergencies.

4. A surgically correctable form of HTN!

5. Majority of the time tumor located in adrenal medulla

21

Catecholamines have two major effects, each mediated by a Beta1 receptor. What are they?

1. Increased heart rate

2. Increased contractility (or force of contraction)

22

Symptoms can be described by the effects that epinephrine and norepinephrine have on the various organ systems:

Catecholamines have two major effects, each mediated by a Beta1 receptor: How does this affect the blood vessels? 2

1. Vasoconstriction of cutaneous blood vessels via Alpha1 receptor

2. Vasodilation of skeletal muscle blood vessels via Beta2 receptor

23

Describe the 90% rule in pheochromocytoma

4

90% tumor (or 10% tumor):

1. 90% of the time they arise from the adrenal medulla (with the other 10% they can arise anywhere but the majority occur in the mediastinum or abdomen)

2. 90% of the time adrenal pheochromocytoma will be unilateral (otherwise it is bilateral and is likely a genetic syndrome)

3. 90% of the time it is not malignant

4. 90% of the time it occurs in adults

24

Keys with pheochromocytoma:

1. History is exceptionally important! Symptoms? 4

2. Diagnosis is made by? 2

3. Once diagnosis is made: Hunt for the source how?

1. Pt usually has episodes of

-hypertension,

-headache,

-palpitation, and

-sweating

2. Demonstrating

-elevated urinary excretion of catecholamines or their metabolites (metanephrines and vanillylmandelic acid)

-DURING a period of hypertension

3.  CT of abdomen with focus on adrenal glands

25

You order a 24 hour urine measurement of what?

The test is positive, a finding that provides nearly conclusive evidence of a pheochromocytoma

A CT scan confirms a 3cm mass on Helen’s right adrenal gland… she needs an adrenalectomy

vanillylmandelic acid (VMA)

26

Surgeons dislike performing surgery on someone with unstable blood pressure… and there is a natural inclination for the body to have a sympathetic response when surgery is performed leaving a patient with a pheochromocytoma to have a high morbidity and mortality unless blood pressure is controlled prior to surgery

1. Current recommendation is to initiate what before surgery?

2. Why do we do this?

3. Then start what 3-4 days after?

4. WHy?

1. initiate alpha blockade first to

2.

-reduce afterload and

-total peripheral resistance…

3. then to start a beta blocker about 3-4 days thereafter

4. to reduce the effects of the increased amount of catecholamines in the bloodstream

27

1. Primary hypothyroidism usually has what kind of onset?

2. Typical labs include? 2

3. Emergency?

1. Primary hypothyroidism usually has insidious onset

2. Typical laboratory findings include

-low T4 and

-high TSH

3. Usually no urgency when suspecting primary hypothyroidism

28

Describe the hypothyroidism feedback system

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29

Myxedema Coma

1. Occurs in individuals with waht?

2. How serious is this?

3. Correct diagnosis requires what?

4. Initiation of treatment is what?

5. Affected patients commonly in what population?

1. long-standing preexisting hypothyroidism presents with life-threatening decompensation

2. **Rare, potentially life-threatening

3. high degree of suspicion

4. empirical decision

5. geriatric

30

Myxedema Coma

Presentation

Severe decline in metabolic function? 8

1. Alteration in mental status

2. Hypothermia

3. Bradycardia

4. Hypotension

5. Hypoventilation (increased CO2 retention)

6. Cardiovascular collapse

7. Decreased drug clearance

8. Usually patient has history of primary hypothyroidism or previous thyroid surgery

31

What precipitates Myxedema coma? 4

1. Medication noncompliance

2. Cold exposure

3. Severe infection

4. Addition of new medications

32

Myxedema Coma

1. Laboratory findings may reveal? 9

2. EKG may demonstrate what? 3

1.

-Anemia,

-hyponatremia,

-hypoglycemia,

-elevated transaminases,

-elevated CPK,

-elevated lactate dehydrogenase,

-hypercholesterolemia,

-decreased PO2,

-increased PCO2

 

2. EKG may demonstrate

-sinus bradycardia,

-prolongation of QT interval, and

-low voltage with flattening or inversion of T waves

33

Myxedema coma tx? 5

Treatment

1. Stabilization (patient may require intubation and mechanical ventilation for airway protection and correction of hypoventilation, hypercapnia, and hypoxia)

2. Correction of hypothermia with cautious use of gentle passive external rewarming

3. IV levothyroxine initial bolus followed by reduced daily dose until orals tolerated

4. Routine administration of glucocorticoid recommended

5. Gentle fluid restriction to correct dilutional hyponatremia

34

1. Classic symptoms in patients with hyperthryoidism include? 6

2. If symptoms are mild, you have time for outpatient evaluation.  High clinical suspicion may warrant what?

1. Classic symptoms in patients with hyperthryoidism include:

-Heat intolerance,

-palpitations,

-weight loss,

-sweating,

-tremor, nervousness,

-weakness, and fatigue

2. If symptoms are mild, you have time for outpatient evaluation.  High clinical suspicion may warrant empiric symptomatic therapy (e.g. beta-blockers)

35

How is thyroid storm different than hyperthyroidism:

Usually precipitated in a previously unrecognized or poorly treated hyperthyroidism patient by? 9

1. Infection,

2. trauma,

3. DKA,

4. MI,

5. CVA,

6. Thromboembolic disease,

7. surgery,

8. withdrawal of thyroid meds,

9. iodine administration

Rare, but a medical emergency

Treatment initiated empirically

36

How is thyroid storm different than hyperthyroidism:

Symptoms that may be seen in thyroid storm NOT necessarily seen with hyperthyroidism? 4

1. Fever

2. Arrhythmia

3. Congestive heart failure

4. CNS dysfunction: Agitation, confusion, delirium, stupor, coma, seizure

37

Thyroid Storm tx?

4

1. Stabilization, airway protection, oxygenation, IV fluids, and monitoring

2. Beta-blockers for severe adrenergic symptoms

3. Antithyroid agents such as PTU or Methimazole

4. Administration of iodine to decrease preformed thyroid hormone

38

Some Important Points

Thyrotoxicosis is not the same thing as thyroid storm

1. The term thyrotoxicosis is used to refer to what?

2. How will the hyroid levels change?

1. accelerated thyroid state

2. Most studies have not demonstrated differences in thyroid hormone levels in patients with symptomatic, uncomplicated hyperthyroidism, and thyroid storm

39

1. What is the single most important initial step in the treatment of DKA?

2. Don’t let a normal what in the patient with DKA fool you!?

 

3. Remember the big three for therapy with DKA includes what? 3

 

4. Those at greatest risk for HHS is what?

1. ***Rapid fluid administration

2. K (or hyperkalemic)  They likely have profound total-body potassium deficits

3. 

-volume repletion (the fundamental one),

-insulin therapy, and

-potassium replacement (with this one the key is frequent monitoring and replacement initiation once K is in normal range!)

4. poorly controlled diabetic elderly patients without free access to water

40

1. The most common cause of acute adrenal insufficiency is what?

2. Remember, only with what will you have hyperpigmentation as a result of increased ACTH?

3. In contrast to indolent and progressive course of chronic adrenal insufficiency, ***adrenal crisis presents what?

4. ***The hypotension in adrenal crisis typically is resistant to what? What do you have to do?

1. sudden withdrawal of exogenous steroids

2. Addison’s disease (antibodies directed against the adrenals)

3. as a life-threatening emergency in which the primary manifestation is hypotension

4. catecholamine and IV fluid administration!  If the missing cortisol is not replaced, death will ensue!

41

1. Presence of unexplained hyponatremia and hyperkalemia in setting of hypotension unresponsive to catecholamine and fluid administration is strong evidence of what?


2. One of the best opportunities to diagnose a pheochromocytoma is in the ED. Why?

 

1. adrenal crisis

2. as the person has likely come in because he/she is in the middle of an attack

42

1. If absolutely everything is slowed down in the patient with long-standing hypothyroidism, then consider what?

 

2. Think of thyroid storm as what? 3

Tx should not be delayed due to waiting for laboratory results

1. myxedema

2. 

-hyperthyroid symptoms

-plus fever and

-CNS disturbances