Healing By Primary Intention Flashcards Preview

Healing By Intention > Healing By Primary Intention > Flashcards

Flashcards in Healing By Primary Intention Deck (6)
Loading flashcards...
1

What occurs during seconds - minutes of injury?

Haemostatsis.

Severed arteries contract -> Narrow space fills with clotted blood -> Dehydration of surface clot and scab forms, acting as a natural dressing.

2

What happens within minutes to hours of injury?

Inflammation - Triggered automatically without waiting for bacteria.

Neutrophils appear at margins to ward off bacteria.

If a wound is kept sterile, the leukocyte count is not high enough to to be considered pus.

3

What happens before 48 hours after injury?

Migration of Cells.

Macrophages appear and scavenge dead neutrophils -> Secrete cytokines to attract cells like fibroblasts and endothelial cells -> Basal epidermal cells meet in middle underneath scab

4

What happens three days after injury?

Regeneration.

Macrophages replace neutrophils -> Granulation tissue (fibroblasts and new capillaries) invade space -> Epithelial cells proliferate, thickening epidermal layer -> Epidermal cells undermine scab so it falls off -> Angiogenesis progresses

5

What happens 7-10 days after injury?

Early scarring.

Wound is filled with fibres which form a fibrous mass -> epidermis keratinises but skin appendages don't form -> White cell infiltrate, oedema and increased vascularity disappear.

6

What happens 1 month - 2 years after injury?

Scar maturation.

Scar has many collagen fibres, few cells and few elastic fibres so little recoil -> As capillaries disappear, old scars appear white.