Wounds

Question 1

Wound definition

Answer 1

Defect or damage in skin caused by chemicals, physical forces, thermal causes or disease

Question 2

2 broad classifications

Answer 2

Wound without tissue loss: eg surgery

Wound with tissue loss: eg trauma or burn wounds

Question 3

Incisions

Answer 3

Regular wound

Caused by a clean sharp edged object

Question 4

Laceration

Answer 4

Rough and irregular wound

Caused by crushing or ripping

Question 5

Abrasion (graze)

Answer 5

Superficial wound where top layers of skin are lost

Caused by sliding on a rough surface

Question 6

Puncture

Answer 6

Caused by sharp pointed object punching skin

Chance of anaerobic bacteria infection

Question 7

Penetration wounds

Answer 7

Caused by entering the body

Question 8

Avulsion

Answer 8

When the integrity of any tissue in the body is compromised

Where something is basically torn off

Question 9

Contusions

Answer 9

A bruise

Caused by blunt force trauma

Question 10

Haematoma

Answer 10

Caused by damage to blood vessel

Blood then accumulates under the skin

Question 11

3 phases of healing

Answer 11

1) Inflammatory
2) Proliferative
3) Remodelling

Question 12

Inflammatory phase

Answer 12

Bleeding first to remove toxins

Vasoconstriction begins to stop bleeding

Coagulation initiated by platelets forming fibrin network

Phagocytes engulf dead cells in the wound

Question 13

Proliferative phase

Answer 13

Granulation tissue builds up in wound space due to fibroblasts and macrophages providing growth factors. (Occurs 2-3 days after wound occurs)

This stimulates fibroplasia and angiogenesis (new blood vessels)

Fibroplasia causes a bed of collagen to fill defect, pulling wound edges together

Question 14

Remodelling phase

Answer 14

3 weeks after wound occurs

Fibroblasts spur on greater collagen formation which forms a helical structure with inter and intra X links

The tissue will not regain the properties of uninjured tissue

Question 15

What pericytes?

Answer 15

Pericytes can differentiate into myofibroblasts

Vascular pericytes can enter the wound bed and can assume a more contractile and matrix depositing phenotype

Question 16

Petroleum impregnated dressing

Answer 16

For clean, healthy and shallow wounds
Use at early stages of wound repair

Use non adhering dressings for exuding wounds such as burns

Question 17

Hydrogel dressings

Answer 17

Hydrogel sheets- for shallow wounds
Can maintain moisture balance while absorbing exudates

Hydrogel gels- for cavities, good for debriding and dislodging

They donate moisture
Promotes collagenase activity, granulation, epithelisation and contraction

Question 18

Hypercolloid dressings

Answer 18

For early to mid repair wounds
Reduces pain and promotes angiogenesis

Used where granulation is necessary
For minimal to moderate exudation

Promotes moist wound healing and granulation

Question 19

Foam dressings

Answer 19

Non adherent

Absorbs large amounts of exudates

For deep wounds with mild to moderate exudates

Best used after granulation to encourage epithelisation and contraction

Question 20

Alginate dressings

Answer 20

Made brown algae

Good gel/film forming properties

Calcium alginate promotes clotting cascade (10x faster compared to petroleum dressings)

For burns, shearing/avulsion, cavity wounds

Best for moderate to highly exuding wounds

Question 21

Film dressings

Answer 21

Semi permeable allowing fluid to evaporate whilst still keeping wound moist

Comfortable and resistant to wear/tear

Prevents bacterial colonisation but does not absorb exudate

Question 22

Natural polymers

Answer 22

Usually protein or polysaccharide in nature

Bio-compatible, degradable and hydrophilic

Does however vary batch to batch and can degrade way too fast

Question 23

Collagen dressings

Answer 23

The protein is made of three peptide chains with triple helical domains

Promotes healing via attachment and migration

Dry collagen physically absorbs blood and traps them which adheres them to the wound site giving mechanical strength

Question 24

Chitosan dressings

Answer 24

Made by acetylating chitin

Active in slightly acidic media and releases beta 1-4 linked-D-glucosamine (used for hemorrhage control)

Promotes fibroblasts, collagen deposition and platelet/RBC mobilisation as well as vasoconstriction

Good film forming properties