Wound Healing

Question 1

Wound classification

Answer 1

Clean- surgical wounds without entering viscus
Clean-contaminated- viscus entered, but under controlled situation
Contaminated- gross contamination, no obvious infection ,most traumatic wounds.
Dirty- Obvious infection

Question 2

Primary Wound Closure

Answer 2

First intention healing. Apposition of wound edges. Most surgical wounds.

Question 3

Delayed Primary Wound

Answer 3

Closure 3-5 days after wounding. Before granulation formation. Mildly contaminated wounds with minimal trauma. Need some cleansing, debridement, and open wound management before closure.

Question 4

Secondary wound closure

Answer 4

Closure >3-5 days after. Granulation tissue formed. Indications for severely contaminated, traumatized wounds.

Question 5

Second Intention

Answer 5

Wound heals by contraction and epithelialization. Problems- excessive wound contamination, failure to completely re-epithelialize. Over proliferation of granulation tissue.

Question 6

Phases of wound healing

Answer 6

Inflammation, Proliferation, maturation.

Question 7

Phase 1

Answer 7

Inflammatory phase- hemostasis, early and late inflammation

Question 8

Phase 1- early inflammation

Answer 8

24-48 hours
Vasodilation, increased endothelial cell permeability, Leukocyte extravasation. Heat, redness, swell, pain, loss of function.
Vasodilation- occurs within minutes. Increased blood flow and local delivery of soluble mediators and inflammatory cells.
Cell permeability- stimulated by hypoxia, endothelial injury, cytokines
Leukocyte extravasation- margination, rolling, stable adhesion, migration
Neutrophils

Question 9

Phase 1- late inflammation

Answer 9

48-72 hours
Macrophages.
Pro to anti-inflammatory

Question 10

Phase 2- Proliferation

Answer 10

Phase 2: Angiogenesis and fibroplasia= granulation tissue. Contraction and epithelialization
Angiogenesis- Stimualted by cytokines. Invading microvascular within 4-6 days.
Fibroplasia- Mesenchymal cells to fibroblasts. 2-5 days. Synthesize collagen (dependent on oxygen and provides tensile strength)
Fibroplasia+ angiogenesis= granulation. Begins 6-7 days. Occurs within ECM.
Contraction- fibroblasts anchored-> myofibroblasts. 6-14 days. Orientate along lines of tension and attack to ECM. Apoptosis after 4-5 weeks
Epithelialization- keratinocytes and epithelial cells. Migrate across wound and contact inhibition. Wound closure

Question 11

Phase 3: maturation

Answer 11

Collagen reorganization. Scar formation- never 100%

Question 12

Impaired Wound Healing

Answer 12

Local factors- wound perfusion, tissue viability, fluid accumulation, infection, tension. Motion, pressure
Systemic- impaired immune function, cancer

Question 13

Impaired Wound- Wound Perfusion

Answer 13

Shock, hypotension, hypovolemia. Severe trauma. Oxygen vital for wound healing and resistance to infection. Promote perfusion by fluid rehydration, prevent hypothermia, hyperbaric oxygen

Question 14

Wound healing- tissue viability

Answer 14

Significant loss of soft tissue. Devitalized or necrotic tissue and foreign debris, prolongs the inflammatory phase, appropriate debridement

Question 15

Wound healing- fluid accumulation

Answer 15

Hematoma or seroma. Pressure inside wound. Enlarged dead space. Ideal media for bacterial proliferation.

Question 16

Wound healing- motion and tension

Answer 16

Disrupt and prolong healing. Avoid with appropriate bandages, partial or complete wound closure, or negative pressure.

Question 17

Wound healing- immune disorder

Answer 17

Attenuated inflammatory response, impaired chemotaxis, and inefficient bacterial killing
Endocrine disorders- Cushing, DM, FIV
Nutrition

Question 18

Debridement

Answer 18

Surgical, mechanical (dressings), biologic (maggots), or enzymatic (collagenase impregnated dressings)

Question 19

Adherent dressings

Answer 19

Dry to dry or wet to dry. Mechanical debridement. Change frequently.

Question 20

Hyperosmotic dressings- Hypertonic saline

Answer 20

use during inflammatory phase, early proliferation, at any stage if wound infected.
20% hypertonicity- antimicrobial, facilitates autolytic debridement.

Question 21

Hyperosmotic dressings- Honey

Answer 21

Use during inflammation or early proliferation. Antibacterial. Enhances autolytic debridement. Reduce edema and inflammation. Enhance granulation tissue and epithelialization. Good with burns.

Question 22

Hyperosmotic dressings- Sugar

Answer 22

Use during inflammatory and early proliferation phase. Hyperosmotic to decrease edema. Cheap. Not to sue with healthy granulation tissue and epithelial tissue

Question 23

Debridement- enzymatic agents

Answer 23

Use during inflammatory and early proliferation. Superficial debridement of poor granulation tissue in chronic wounds. Collagenase.

Question 24

Debridement- maggots

Answer 24

Inflammatory or early inflammation. Secrete digestive enzymes to dissolve necrotic tissue. Can destroy healthy epithelium

Question 25

Antimicrobial dressings- Triple antibiotic ointment

Answer 25

Inflammatory phase. Reduces microbial burden. Keeps surface moist to enhance epithelialization

Question 26

Antimicrobial dressings- silver sulfadiazine

Answer 26

Inflammatory, early proliferation, infected wound at any stage. Consistent antimicrobial activity. 3 day and 7 day formulation. Does not debride

Question 27

Antimicrobial dressings- hydrogel

Answer 27

Inflammatory and proliferation stages. Provides moisture with minimal exudate (promotes epithelialization)

Question 28

Vacuum assisted closure

Answer 28

Improves wound perfusion, reduces edema, stimulate granulation tissue, remove exudate. Do not use in infected wounds