Lecture 7 – Endocrine Disorders

Endocrine System – Focus on Thyroid & Adrenal Glands

Thyroid Gland

  • Function: Regulates metabolism.

Hyperthyroidism

  • Definition: “Hypermetabolism,” where the metabolism is elevated.
  • Signs and Symptoms:
    • Weight loss
    • High heart rate (tachycardia) and blood pressure (hypertension)
    • Irritability
    • Heat intolerance, cold tolerance
    • Exophthalmos: Bulging eyes
  • Also Known As: Graves’ disease (“running yourself into the grave”).

Treatments for Hyperthyroidism

  1. Radioactive Iodine:
    • Patient should be isolated for 24 hours (limit visitors).
    • Handle urine carefully (flush 3 times); if spilled, call the hazmat team (urine is the primary radioactive risk).
  2. PTU (Propylthiouracil):
    • Lowers thyroid activity (“Puts Thyroid Under”).
    • Immunosuppressant: Monitor WBC count closely.
  3. Thyroidectomy (surgical removal):
    • Total Thyroidectomy:
      • Requires lifelong hormone replacement.
      • Risk of hypocalcemia (due to possible removal of parathyroid glands) → watch for Trousseau’s sign and Chvostek’s sign.
    • Subtotal Thyroidectomy:
      • Does not require lifelong hormone replacement.
      • Risk of Thyroid Storm post-op.

Thyroid Storm (Crisis)

  • Definition: A life-threatening condition that occurs with untreated or undertreated hyperthyroidism.
  • Signs and Symptoms:
    1. Very high fever (≥105°F).
    2. Extremely high blood pressure (e.g., 210/180).
    3. Severe tachycardia (heart rate of 180-200).
    4. Psychotic delirium (medical emergency, can lead to brain damage).
  • Treatment:
    • Focus on cooling and oxygenation.
    • First: Apply ice packs.
    • Best: Use a cooling blanket.
    • Oxygen at 10L via mask.
    • Avoid Tylenol, as it won’t be effective.
    • In sequence: oxygen → ice packs → cooling blanket.
    • Never leave the patient unattended.

Post-Operative Risks for Thyroidectomy

  1. First 12 hours:
    • Focus on airway and hemorrhage.
  2. 12-48 hours:
    • Total Thyroidectomy: Watch for tetany (due to low calcium) as this can obstruct the airway.
    • Subtotal Thyroidectomy: Watch for thyroid storm.
  3. After 48 hours (up to 72 hours):
    • Risk of infection (but never prioritize infection as a risk in the first 72 hours post-op).

Hypothyroidism

  • Definition: “Hypometabolism,” where the metabolism is decreased.
  • Signs and Symptoms:
    • Weight gain
    • Cold intolerance, heat tolerance
    • Low heart rate and blood pressure
    • Myxedema: Severe hypothyroidism.

Treatment for Hypothyroidism

  • Medication: Administer thyroid hormone replacement (Synthroid/Levothyroxine).
  • Caution:
    • Avoid sedating these patients; it can lead to coma.
    • Pre-op consideration: Always question an order for sedatives like Ambien at bedtime.
    • Ensure patients continue taking their thyroid medication, even if NPO (do not hold thyroid meds unless explicitly ordered).

ADRENOCORTEX Diseases (Start with A & C)

  • Examples include Cushing’s, Conn’s, and Addison’s diseases.

Addison’s Disease

  • Definition: Undersecretion of the adrenal cortex.
  • Signs and Symptoms:
    • Hyperpigmentation (tanned appearance).
    • Inability to adapt to stress: These patients cannot increase blood glucose or blood pressure during stress, leading to dangerously low levels.
    • Risk: Even minor stress (e.g., a dentist visit or fender bender) can lead to shock and death due to low blood pressure and glucose.
    • Rare Condition: For every 600 Cushing’s patients, there is 1 Addison’s patient. (Example: JFK had Addison’s disease, and the stress of his injury contributed to his death.)
  • Treatment: Glucocorticoids (steroids) such as prednisone, dexamethasone, and hydrocortisone.
    • Memory Tip: In Addison’s disease, you need to “ADD a SONE” (steroids ending in “-sone”).

Cushing’s Disease

  • Definition: Oversecretion of the adrenal cortex (“Cushy = More!”).
  • Signs and Symptoms:
    • Physical Appearance:
      • Moon face (puffy, round face).
      • Hirsutism (excessive facial hair).
      • Truncal obesity (large abdomen with thin arms and legs due to muscle wasting).
      • Buffalo hump (fat deposit on the upper back).
      • Gynecomastia (breast development in men).
      • Striae (stretch marks) and easy bruising.
    • Fluid and Electrolyte Imbalance:
      • Retains sodium and water, losing potassium.
    • Emotional Symptoms: Irritability and mood swings.
    • Immunosuppression: Prone to infections.
    • Hyperglycemia: High blood glucose levels.
    • Memory Tip: Think of “Cushman”—the classic presentation of Cushing’s.
  • Treatment: Adrenalectomy (removal of the adrenal glands).
    • Note: Bilateral adrenalectomy can lead to Addison’s disease, requiring lifelong steroids, potentially leading to a “Cushman” appearance again due to steroid use.

Laminectomy (Neuro)

  • Definition: A surgical procedure that removes the lamina (the back part of the vertebra) to relieve pressure on the spinal cord or nerves. This is also known as decompression surgery.

Why is a Laminectomy Done?

  • Purpose: To relieve nerve root compression.
  • Signs of Nerve Root Compression (The 3 P’s):
    • Pain
    • Paresthesia (numbness and tingling)
    • Paresis (muscle weakness)

Key Consideration: Location

  • The location of the laminectomy is crucial in neuro questions.
  • Common Locations:
    1. Cervical (neck)
    2. Thoracic (upper back)
    3. Lumbar (lower back)

Pre-Op Assessment Based on Location:

  • Cervical (neck): Assess airway and function of arms/hands.
  • Thoracic (upper back): Assess cough reflex and bowel function.
  • Lumbar (lower back): Assess bladder function (e.g., when they last voided) and leg function.

Post-Op Care (Spinal Surgery)

  1. Log roll the patient (maintain spinal alignment).
  2. Don’t dangle the patient’s legs.
  3. Avoid sitting for longer than 30 minutes.
  4. Patients can walk, stand, and lie down without restriction.

Potential Complications Based on Location:

  • Cervical: Risk for pneumonia.
  • Thoracic: Risk for pneumonia and paralytic ileus.
  • Lumbar: Risk for urinary retention and leg issues.

Discharge Teaching

Temporary Restrictions (for 6 weeks):

  1. Do not sit for more than 30 minutes.
  2. Lie flat and log roll when moving.
  3. No driving.
  4. No lifting more than 5 pounds (equivalent to a gallon of milk).

Permanent Restrictions:

  1. Never lift objects by bending at the waist.
  2. Cervical laminectomy patients: Do not lift anything over the head.
  3. Avoid activities involving jerking (e.g., horseback riding, roller coasters).

Additional Terminology:

  • Anterior Thoracic Laminectomy: Access through the chest to the spine.
  • Laminectomy with Fusion: Involves a bone graft from the iliac crest (hip) with two incisions—one on the hip and one on the spine.
    • Hip incision: More pain, bleeding, and drainage.
    • Both incisions: Equal risk of infection.
    • Spinal incision: Highest risk of graft rejection.

Key Reminder:

  • The most important thing in any neuro question is the location of the laminectomy.

Posted

in

by

angelicasale08

Tags: