NRE Step 1: Surgery Made Simple – Pass with Precision

Surgery Basics

Burns: These are skin injuries.
- 1st degree: Only the top layer of skin is hurt.
- 2nd degree: Top layer and the layer under it are hurt, causing blisters.
- 3rd degree: All skin layers and the fat layer underneath are hurt, causing a scar.
- A type of germ called Pseudomonas Aeruginosa can infect burns.
- Fluid replacement: Giving fluids back to the body is important for burns.
- Parkland formula: This is a way to figure out how much fluid to give. You multiply 4 by the person’s weight (in kilograms) and by the size of the burn. Half of this fluid is given in the first 8 hours, and the other half in the next 16 hours.
- Rule of Nines: This is a way to estimate the size of a burn.
  - Head = 9%
  - Each arm = 9%
  - Chest and tummy (front) = 18% (9% for chest, 9% for tummy)
  - Back = 18% (9% for upper back, 9% for lower back)
  - Each leg = 18% (9% for front, 9% for back)
  - Groin area = 1%

Shock

Shock is when your body doesn’t get enough blood flow.
Hypovolemic shock: This happens when your body loses too much fluid.
- Causes include: not drinking enough, diarrhea, burns, or bleeding a lot.
- First sign: Heart beats very fast.
- Skin feels cool.
- Treatment: Blood transfusions (giving blood).
Obstructive shock: This happens when something blocks blood flow.
- Example: Fluid around the heart (cardiac tamponade).
Cardiogenic shock: This happens when your heart can’t pump blood well.
- Causes include: heart attack, weak heart muscle, or faulty heart valves.
Distributive shock: This happens when blood vessels get too wide.
- Skin feels warm.
- Anaphylactic shock: A very bad allergic reaction.
  - Caused by a strong reaction to something, making body parts swell.
  - Treated with adrenaline.
- Septic shock: Caused by a very bad infection.
  - Blood vessels get wide, skin is warm, and there’s a high fever.
  - Treated with antibiotics.

Spinal Cord Injury

This can cause a problem with how the body balances itself, leading to blood vessels getting too wide.
Treatment: Fix the cause of the injury.

Wound Healing

Scar: The new tissue that grows after an injury.
- Hypertrophic scar: A scar that is raised above the skin but stays within the original wound area.
- Keloid: A scar that grows above the skin and goes beyond the original wound area.
How wounds heal:
- Primary intention: The wound edges are brought together (like with stitches).
- Secondary intention: The wound is left open to heal on its own, forming new tissue. This can leave a scar.
Delayed healing: Wounds can take longer to heal if they get infected many times.

Hernias

A hernia is when an organ pushes through a weak spot in a muscle.
Indirect hernia:
- More common in young people.
- The organ comes out through a deep opening and then a top opening.
- You usually can’t see a bulge.
Direct hernia:
- More common in older people.
- The organ pushes through a specific layer of muscle.
- You usually can see a bulge.
Epigastric artery hernia: This hernia happens in a specific spot near an artery.

Scrotal Swelling

Testicular torsion:
- Causes a lot of pain.
- Prehn’s sign is negative (pain does not get better when the testicle is lifted).
Epididymitis:
- Causes pain.
- Prehn’s sign is positive (pain gets better when the testicle is lifted).
Scrotal hernia: Swelling in the scrotum.
Hydrocele: Fluid around the testicle.
Varicocele: Swollen veins in the scrotum, often on the left side, feeling like a “bag of worms.”
- Treatment: Surgery.
Checking scrotal swelling:
- If the doctor can’t feel above the swelling, it might be a hernia.
- Transillumination test:
  - If light shines through (positive), it’s a hydrocele.
  - If light doesn’t shine through (negative), it’s a hernia.

Glasgow Coma Scale (GCS)

Eyes:
- Open when told: 4
- Open to sounds: 3
- Open to pain: 2
- No opening: 1
Words:
- Talks normally: 4
- Wrong words: 3
- Sounds only: 2
- No sound: 1
Movement:
- Moves when told: 6
- Moves to find pain: 5
- Moves away from pain: 4
- Bends strangely: 3
- Stiffens strangely: 2
- No movement: 1

Head Injuries

Epidural Hematoma: Blood on top of the brain’s cover.
- Often from the MMA (a blood vessel).
- Person might feel fine then get worse.
- Looks like a round shape.
Subdural Hematoma: Blood under the brain’s cover.
- From small veins.
- Looks like a curved shape.
Medicine: CCB Nimodipine

Neck Lumps

How long it’s been there
Types of Lumps:
- Swollen lymph node (Lymphadenitis): Happens when there’s an infection.
- Dermoid cyst: A lump you’re born with, usually in the middle or upper part of the neck.
  - Treated with surgery.
- Sebaceous cyst: A lump with pus, keratin, and sebum.
- Lipoma: A fatty lump.
  - Can be painful.
  - Can be related to Hashimoto thyroiditis.
Alarming Signs: Bad signs.
Thyroglossal duct cyst: A lump in the middle of the neck that moves when you stick out your tongue.
Ectopic thyroid: Thyroid tissue in the wrong place, like under the tongue.
Thyroid Cancer:
- Papillary CA: Most common type (70-80%).
  - Can be caused by radiation as a child.
  - Spreads through lymph system.
  - Good outlook.
- Follicular CA:
  - Happens around ages 40-60.
  - Spreads through blood.
  - Good outlook if found early, bad if found late.
- Medullary CA:
  - Has a special marker called Calcitonin.
  - Can cause muscle spasms.
- Anaplastic CA:
  - Very bad outlook.
  - Rare.
  - Usually in people over 60.

Thyroid Scan

Thyroid Surgery Problems

Breast Lumps

Location: Often in the upper, outer part of the breast.
Risk Factors:
- Older age.
- Family history (BRCA1, BRCA2 genes).
- Lots of estrogen exposure.
- Drinking alcohol.
Alarming Signs:
- Breasts look different from each other.
- Fluid coming from the breast.
- A new lump.
- Skin looks dimpled.
Types of Breast Lumps/Issues:
- Fibroadenoma:
  - Common in young women (15-35 years old).
  - Soft, not painful, can move around.
  - Not cancer.
  - Can be found with ultrasound.
- Phyllodes tumor:
  - Lump with a “leaf-like” shape.
- Mastitis: Breast discharge, fever, chills.
- Abscess: A pocket of pus.
- Paget disease: Affects the nipple.
- Fat necrosis: Breast tissue dies after an injury.
Invasive ductal CA: A type of breast cancer.

Gynecomastia:

Enlargement of breast tissue in males.
Can be caused by:
- Liver problems.
- Klinefelter syndrome.
- Testicular tumor.
- Certain medicines (like cimetidine).