Exam 1 - Thyroid and Shock

Question 1

Why is it hard to diagnose a thyroid hormone disorder?

Answer 1

Thyroid hormones are very lipid soluble, staying inside plasma protiens; making it hard to quantify the free level of hormone.

Question 2

What may be the only symptom of hyperthyroidism?

Answer 2

Increased HR at rest

Question 3

What does PTH control?

Answer 3

Blood calcium levels

Question 4

Why major concern is there for thyroid surgeries or invasive airways (cricothyrotomy)?

Answer 4

The thyroid gland is highly vascular and can lead to major blood loss

Question 5

The nerves that innervate the voice box are branched from the ____ ?

Answer 5

Vagus nerve

Question 6

What are 1 and 2 below?

Answer 6

1. Right recurrent laryngeal nerve or right inferior laryngeal nerve
2. Left recurrent laryngeal nerve or left inferior laryngeal nerve

Question 7

What happens if we lose one laryngeal nerve?
Both laryngeal nerves?

Answer 7

1. raspiness of voice
2. complete loss of voice

Question 8

What does the T stand for in T3/T4?

Answer 8

Tyrosine

Question 9

What does the 3 and 4 stand for in T3/T4?

Answer 9

The number of iodide groups attached to the tyrosine

Question 10

The thyroid gland produces ____ % T3 and ____ % T4?

Answer 10

7%, 93%

Question 11

What is another name for T4?

Answer 11

Thyroid hormone or thyroxine

Question 12

What is another name for T3?

Answer 12

Thyroid hormone and 3,5,3 - Triiodothyronine

Question 13

How are the molecules of T3 and T4 produced?

Answer 13

Tyrosine + iodine → Monoiodotyrosine (T1)
Tyrosine + 2 iodine → Diiodotyrosine (T2)
T1 + T2 → T3
T2 + T2 → T4

Question 14

How are the structures of T1/T2 different from T3/T4?

Answer 14

T3 and T4 have two benzene rings

Question 15

How much iodine do we need in our diet for normal thyroid hormone production?

Answer 15

50 mg/year

Question 16

Where is TSH produced and release from?
What is another name for TSH?

Answer 16

• The anterior pituatary gland (adenohypophysis)
• Thyrotropin

Question 17

What compound and organ controls TSH release?

Answer 17

TRH (Thyrotropin Releasing Hormone) by the hypothalamus

Question 18

What 3 things carry thyroid hormone around the body?
Where are these produced?

Answer 18

1. TBG - thyroxine binding globulin
2. Thyroxine binding pre-albumin
3. Albumin
   All are made by the liver

Question 19

Which thyroid hormone has the primary effect on the cells?

Answer 19

T3

Question 20

Thyroid hormone binds to the ____ in the ____ of cells.
This causes ____, which activates synthesis of new proteins.

Answer 20

thyroid hormone receptor, nucleus, gene transcription

Question 21

What intracellular process create an increased metabolism after thyroid hormone activation? (there are a lot.)

Answer 21

↑ Mitochondria
↑ N/K/ATPase
↑ O2 consumption
↑ Glucose absorption
↑ Gluconeogenesis
↑ Glycogenolysis
↑ Lipolysis
↑ Protein synthesis
↑ BMR

Question 22

What are CV effects from increased metabolism?

Answer 22

↑ CO (from reduced SVR)
↑ Tissue blood flow
↑ HR
↑ Respiration (to meet cellular O2 demands)

Question 23

What population are highly dependent on normal thyroid hormone levels?

Answer 23

Children - thyroid hormone is necessary for proper growth and development

Question 24

What positive side effect occurs from hyperthyroidism?

Answer 24

Blood cholesterol levels are low from increased cellular use

Question 25

How long does it take for thyroid hormone to have an effect? Peak effect?

Answer 25

- 6-8 hrs - 10 days

Question 26

What blood lab values would be seen in a patient with a pituatary tumor?

Answer 26

↑ TSH, ↑ Thyroxine, ↓ TRH

Question 27

What blood lab values would be seen in a patient with a thyroid tumor?

Answer 27

↑ Thyroxine, ↓ TRH, ↓ TSH

Question 28

What blood lab values would be seen in a patient with a hypothalamic tumor?

Answer 28

↑ TRH, ↑ TSH, ↑ Thyroxine

Question 29

This enzyme converts T4 to T3 inside the cell?

Answer 29

Iodinase

Question 30

What is Grave's disease?

Answer 30

Autoimmune-mediated hyperthyroidism caused by antibodies that activate TSH receptors, increasing thyroid hormone release

Question 31

What eye condition is caused by high levels of thyroid hormone?

Answer 31

Exopthalmos

Question 32

This disease creates antibodies that destroy the thyroid gland?

Answer 32

Hashimoto's Thyroiditis

Question 33

What are the sequale of low iodine intake?

Answer 33

↑TSH and TRH in an attempt to stimulate thyroid hormone production - causing a goiter But no thyroid hormone can be produced without iodine (no exopthamos)

Question 34

What treatment is common for thyroid cancer?

Answer 34

I-131 - radioactive iodine

Question 35

What counterintuitive effect may high levels of iodine have?

Answer 35

May actually decrease thyroid hormone release - can be used to treat hyperthyroidsim acutely

Question 36

What drug can cause hypothyroid effects?

Answer 36

Amiodarone - packaged with a high level of iodine; stunting the thyroid gland

Question 37

What concern do we have for older patients with hypothyroidism?

Answer 37

Less metabolism = less cholesterol use = athlerosclerosis

Question 38

What do we do in anesthesia that can cause neurogenic shock?

Answer 38

General anesthesia and high spinal - takes SNS control of CV system offline

Question 39

What causes the deleterious effects seen in anaphylactic shock?

Answer 39

Histamine - causes widespread vasodilation

Question 40

Sepsis is usually caused by gram ____ bacteria.

Answer 40

Positive

Question 41

At what percentage of blood loss are both CO and arterial pressure maintained?

Answer 41

10 %

Question 42

What happens to our arterial blood pressure and CO at 20 % blood loss? Why is this bad for us in anesthesia?

Answer 42

- Arterial pressure remains normal from vasoconstriction by the SNS Increased SVR reduces CO - Most of the time we are not directly measuring CO, so we may see a normal BP and not realize CO may be dropping

Question 43

A drop in MAP of ____ % of normal from volume loss is survivable. But a MAP less than ____ % of normal is not.

Answer 43

- 50 - < 45

Question 44

What compensations are made by the body with large volume losses?

Answer 44

- ↑ SNS - ↑ volume retention - Fluid shift from plasma and cells into CV system - Shift of blood storage pools into CV system

Question 45

What is progessive and non-progessive shock?

Answer 45

Non-progessive: survivable with body compensations Progressive: not survivable despite body compensations

Question 46

Where can the body recruit more blood from during shock?

Answer 46

Spleen, pulmonary circulation, and GI system

Question 47

Explain the renal physiology happening in this diagram:

Answer 47

The heart is severely failing causing a reduced CO and BP. The kidneys only monitor BP and because its low, it begins to retain volume in an attempt to reach a normal BP. It continues to do this even when it is harmful, causing and overstretched heart and even further reducing CO (point D-F).

Question 48

How can we prevent the kidneys from causing harm from too much fluid retention?

Answer 48

Diuretics - allows body to maintain adequate (not perfect) blood pressure, without overloading the heart