Wound Healing

What vasoactive substance produces vasoconstriction and vasodilation during tissue coagulation?

• Prokinin

• Histamine

• Bradykinin

• Serotonin

Answer explanation

Serotonin is released by platelets in blood to help heal wounds. It also causes the tiniest blood vessels, arterioles, to narrow, which slows blood flow and helps clots to form.

According to Bailey's model, rearrange phases of tissue repair.

• Inflammatory

• Fibroplasia

• Coagulation

• Remodelling

Answer explanation

Wound healing is classically divided into 4 stages: (A) coagulation, (B) inflammation, (C) fibroplasia, and (D) remodeling. Each stage is characterized by key molecular and cellular events and is coordinated by a host of secreted factors that are recognized and released by the cells of the wounding response.

During fibroplasia phase, it will take ​ (a)   hours for migration of fibroblasts take place into the wound.

• 48-72
• 12-24
• 24-48
• 72-96

Answer explanation

Fibroblasts begin entering the wound site two to five days after wounding as the inflammatory phase is ending, and their numbers peak at one to two weeks post-wounding.

Collagen serve as​ (a)   .

• strength and support
• cell adhesion
• locomotion
• expansion and contraction

Answer explanation

Collagen is protein molecules made up of amino acids. It provides structural support to the extracellular space of connective tissues.

Maximum strength of a scar versus the unwounded skin is ​ (a)   .

• 80%
• 60%
• 25%
• 90%

Answer explanation

A healed wound only reaches approximately 80% of the tensile strength of unwounded skin.

Reorder the rate level of contraction from most to least.

• STSG

• Flap

• FTSG

Answer explanation

A split-thickness graft (STSG) is composed of epidermis and a variable amount of dermis, a full-thickness graft (FTSG) includes all the layers of the skin.

Intact dermis have ​ (a)   of type I collagen and ​ (b)   of type III collagen.

• 80%
• 20%
• 50%
• 60%
• 40%

Answer explanation

In the skin, collagen type I constitutes 80–85% of the dermal ECM, while collagen type III constitutes about 11-20%.

What collagen synthesis is needed during the process ?

• Vitamin C

• Supplements

• Proteins

• All of it

Answer explanation

Vitamin C is the essential cofactor for the two enzymes required for collagen synthesis: prolyl hydroxylase (to stabilize the collagen molecule) and lysyl hydroxylase (to give structural strength cross-linking)

The optimal time to operate on irradiated tissue is between ​ (a)   and ​ (b)   .

• 3 weeks
• 3 months
• 6 weeks
• 4 weeks
• 6 months

Answer explanation

Surgical procedures performed on previously irradiated tissue are associated with an increased morbidity in terms of delayed wound healing and breakdowns. The timing of these procedures has been ideally kept as three weeks to three months after the completion of radiation.

Which Vitamin if given to a patient who is receiving prolonged prednisone treatment for rheumatoid arthritis has the potential to attenuate the prednisone's negative effects on wound healing?

(a)  

Answer explanation

Vitamin A has the ability to reverse the inhibitory effects of chronic corticosteroids on cutaneous and fascial wound healing.