Skin

Question 1

3 Layers of the skin

Answer 1

Epidermis

Dermis

Hypodermis / Subcutaneous

Question 2

Function of the epidermis

Answer 2

The outer layer ofskin

Provides a waterproof barrier

Provides structure

Replaces itself approximately once every month

Question 3

Colour of the skin is affected by what 3 factors

Answer 3

Melanin
Levels of oxygenation of haemoglobin
Levels of bile pigments

Question 4

Components of the dermis

Answer 4

Blood vessels
Lymph vessels
Sensory nerve endings
Sweat glands
Hairs, arrector pili muscles & 
	  Sebaceous glands.

Question 5

Function of the hypodermis / subcutaneous

Answer 5

The deepest and thickest layer

Also known as the subcutaneous layer
Mainly for fat storage

Question 6

Functions of the skin

Answer 6

Protection
Regulation of body temperature
Formation of vitamin D
Cutaneous Sensation
Absorption
Excretion.

Question 7

Definition of primary wound healing

Answer 7

The damaged tissue edges are close
Includes surgical incisions
Three stage healing process:

Question 8

3 stages of primary would healing

Answer 8

Inflammation:
This happens within the first few hours
The area becomes inflamed creating a clot

Proliferation:
Epithelial cells cover the wound through the clot
The epidermis grows and meets until full thickness
Granulation tissue restores blood supply to the wound

Maturation:
Granulation tissue is replaced by fibrous scar tissue

Question 9

Definition of secondary wound healing

Answer 9

A large wound involving considerable tissue loss

Wound edges are not and cannot be brought near each other

Question 10

Three stages of secondary wound healing

Answer 10

Inflammation:
On the surface of healthy tissue
Slough removes pathogens and dead tissue

Proliferation:
Starts as granulation tissue on ‘wound bed’
Good blood supply and lots of phagocytes
Epithelial cells at the edges grow towards the centre

Maturation:
Scar tissue replaces granulation tissue to full thickness
Scar tissue is shiny with no sweat glans, hair follicles or sebaceous glands.

Question 11

Complications in wound healing

Answer 11

Infection:
Happens when bacterial, virus or fungi get into the wound
Pus consists of dead white blood cells, dead local cells, cell debris and some inflammatory cells
Osteomyelitis is an infection of the bone and is a very serious infection that can be caused by an open wound

Wound necrosis / death
Due to poor wound blood supply and prolonged infection

Oedema:
Fluid retention around wounds that can obstruct the healing process

Dermatitis:
Skin condition that reduces wound healing tissue proliferation.