PreTest Surgery: Skin: Wounds, Infections, and Burns; Hands; Plastic Surgery

Question 1

How do you determine the appropriate margin for removal of a melanoma?

Answer 1

• < 1 mm deep = 1 cm margin
• 1 - 4 mm deep = 2 cm margin
• > 4 mm deep = 3 cm margin

Question 2

Review the timeline for cell type in wound healing.

Answer 2

• Day 1-2: neutrophils
• Day 3: fibroblasts
• Day 5-7: macrophages

Question 3

How is pyoderma gangrenosum treated?

Answer 3

Systemic corticosteroids and immunosuppressants

Topical isn’t effective enough.

Question 4

Frostbite without necrosis should be treated with ___________.

Answer 4

submersion in water slightly warmer than the body temperature

Question 5

List the four classes of surgery cleanliness.

Answer 5

• I: clean – no entry into GI or respiratory structures
• II: clean/contaminated –GI or respiratory structures entered, but no obvious spillage
• III: contaminated –obvious spillage of respiratory/GI fluids
• IV: dirty –spillage of GI/respiratory contents prior to surgery with significant time

Question 6

Mohs is used to treat which lesions?

Answer 6

BCC and SCC

Question 7

Describe the basic schema to surgical treatment of burns.

Answer 7

• First: perform escharotomy at the first sign of hemodynamic instability. (The charred, leathery scar prevents tissue expansion. As distal tissues try to heal, they will be limited by the eschar. The surgery thus involves cutting through the eschar to release the pressure.)
• Second: excise deep partial and full-thickness burns on day 3-7
• Last: replace damaged skin with autografts

Question 8

List the three agents used to treat burns and the side effects of each.

Answer 8

• Silver nitrate: hyponatremia, hypokalemia, hypocalcemia, and hypochloremia)
• Silver sulfadiazine: neutropenia
• Mafenide: metabolic acidosis

Question 9

The most common cancer to arise on the lip is ___________.

Answer 9

SCC

Question 10

What is tertiary intention?

Answer 10

Repeatedly treating a wound (antibiotics or debridement) before surgically closing it

Question 11

How do you manage oral hairy leukoplakia?

Answer 11

OHL is a premalignant lesion; only about 5% transition to cancer. The best thing to do is have the person maintain good oral hygiene and avoid alcohol/tobacco.

Question 12

Review the definition of these terms:

• Split-thickness graft
• Full-thickness graft
• Composite graft
• Pedicle graft
• Free flap

Answer 12

• Split-thickness graft: just the epidermis
• Full-thickness graft: both epidermis and dermis
• Composite graft: epidermis, dermis, and subcutaneous tissue
• Pedicle graft: taking a flap of skin and moving it to another are while keeping one edge anchored
• Free flap: completely severing the flap of skin and reanastomosing it to another supply

Question 13

Best initial diagnostic for compartment syndrome?

Answer 13

US with Doppler

Question 14

Wounds that occurred more than ________ hours previous to presentation should not be closed unless the patient is hemodynamically unstable. These are likely to be contaminated and will become infected if closed.

Answer 14

6

Question 15

Review the Parkland formula.

Answer 15

4 x body weight in kg x % body burnt

This is the total volume needed in mL. Give half over the first 8 hours and the other half over the next 16.

So say I burned half of my 70 kg body:

4 x 70 x 50 = 14,000 mL

So 7,000 mL / 8 hours = ~900 mL/hr

7,000 mL / 16 hours = ~450 mL/hr

Compare this to my normal calculate MIVF of 110 mL/hr!

Question 16

Mohs surgery is reserved for what type of lesion?

Answer 16

BCC or SCC on areas that you want to aesthetically spare from excision (face, neck, ears)

Question 17

They give you two patients with foot ulcers, both have diabetes. One ulcer is on the toe and the other is on the heel. Which is an ischemic and which is a diabetic ulcer?

Answer 17

The toe is ischemic!

Remember that ischemic ulcers appear distally due to poor perfusion, so tips of toes are commonly affected.