Hyperthyroidism

Question 1

A 38-year-old lady going for surgery. Pre-op bloods showed. High T3, high T4, low TSH
Q1. Diagnosis?

Answer 1

Hyperthyroidism

Question 2

Q2. What are the causes of hyperthyroidism?

Answer 2

Most probably is idiopathic,
It could be due to goiter, inflammation like Hashimoto’s in early stages, adenoma of thyroid, viral infection, central due to hypersecreations form pituitary gland

Question 3

Q3. Talk about Thyroid hormone metabolism

Answer 3

Thyroid Hormone Metabolism

• Deiodination of T4 and T3: Thyroxine (T4) and triiodothyronine (T3) undergo deiodination in the liver, kidneys, and many other tissues. These deiodination reactions serve to:
  
  • Catabolize the hormones: Breaking down thyroid hormones for elimination.
  • Provide a local supply of T3: T3 is the primary mediator of the physiological effects of thyroid hormones.
• Source of Circulating T3: Only about 13% of circulating T3 is directly secreted by the thyroid gland. The remaining 87% is produced by the peripheral conversion (deiodination) of T4 to T3.

Question 4

Q4. What are the stages of thyroid hormone production?

Answer 4

lodide ions enter the thyroid follicular cell by active pumping
. lodide is converted to iodine by TOP
. lodine combines with tyrosine forming: monoiodotyrosine (MIT) and diiodotyrosine (DIT)
. MIT + DIT = T3 (tri iodotyrosine)
. DIT + DIT = T4 (tetra iodotyrosine)

Question 5

Q5. What are the functions of thyroxine (T4)?

Answer 5

Heart –> chronotropic and inotropic
Adipose tissue – > catabolic (lipolysis)
Muscles – > catabolic (ms break down)
Bone – > developmental
CNS – > developmental
Gut – > metabolic
Lipoprotein – > metabolic

Question 6

Q6. What are the possible complications if patient went to surgery without
correction?

Answer 6

Thyroid storm
MI

Question 7

Q7. What are the anaesthetic considerations?

Answer 7

Thyroid storm.
AF
HIGH RISK KF OF MI

Question 8

Q9. What are the clinical picture of thyroid crisis (storm)?

Answer 8

Dehydration
Hyper pyrexia
AF
Restlessness
Hyperglycemia
Confusion
Could lead to Mi
x

Question 9

Given this ECG :-

Q8. Diagnosis?

Answer 9

ABSENT P WAVE AND IRREGULAR PUSLE SO AF

Question 10

Q10. Management?

Answer 10

CCRISP
O2 - IV fluids - cooling and ice packs – diuretics for cardiac failure – Digoxin in uncontrolled AF – Sedation – IV hydrocortisone
Definitive – > Carbimazole / Lugol’s iodine / propranolol IV 1-2 MG
OR ORAL 40 MG 6HRLY
May give ACEI

Question 11

Q11. What is Lugol’s Iodine? How does it act? How does the radioactive iodine act?

Answer 11

Aqueous iodine in form of potassium iodide and iodine in water
- Inhibit thyroid hormones synthesis and conversion. / Decrease vascularity and inhibit iodine binding.
Cannot use for long term
- radioactive iodine – destroy thyroid tissue and leading to decrease thyroid hormones

Question 12

Q12. Where to manage patient?

Answer 12

ITU