Inflammation PP

Question 1

Tissue Healing/Inflammation

Answer 1

Vascular Phase
Inflammatory Exudate
Proliferation Phase
Remodelling Phase

Question 2

1. Vascular Phase

Tissue Healing/Inflammation

Answer 2

Bleeding/injury followed by vasoconstriction of blood vessels to decrease loss of blood
Vascular spasm
- direct trauma vessel
- local release of chemicals from injured cells e.g. release of mast cells which contain heparin (prevents coagulation), serotonin (activates the pain signal and increase permeability), histamine (causes vasodilation and increase permeability of blood vessels)
Vascular damage triggers primary homeostasis
- prompts clot formation
- accumulation of inflammatory mediators e.g. histamine, bradykinin
Chemical stimulus to initiate other healing phases

Question 3

2. Inflammatory Phase:

Tissue Healing/Inflammation

Answer 3

Defence cells to damaged area
Protects against infection
Constriction can lead to hypoxia (decrease oxygen in the blood), so vessels dilate to allow more oxygen and chemical mediators (helps to clear toxins and increases blood flow to the area carrying white blood cells)
This leads to increased swelling
Exudate:
Inflammatory mediators change size so the spaces between cells become bigger, leading to more permeable vessels and increased swelling.
- there is a loss of a protein rich fluid (exudate)
- Increased viscosity in the capillaries (reduced blood flow), making it a rich environment for tissue repair
Monocytes from inflammatory exudate become macrophages and engulf and dispose of necrotic/pathogenic material e.g. bacteria = phagocytosis
An end product of phagocytosis is lactic acid which is a stimulant of the next phase
Fibrinogen converted to thick network of fibronectin: a ‘glue’ which traps invading microbes and stops their spread to surrounding tissue, preventing infection
Angiogenesis (or neovascularisation): capillaries begin to form moving towards injury site. New blood vessels supply oxygen and nourishment to the injured tissue
Treatment at this stage can aggravate symptoms

Question 4

3. Proliferation Phase:

Tissue Healing/Inflammation

Answer 4

• 24-48 hours after injury – weeks/months
• Epithelialisation occurs within hours of injury: undamaged epithelial cells begin to reproduce allowing a ridge to form around the edge of the wound
• Once the wound has been cleared by phagocytosis the macrophages direct fibroblasts into the injured area then begin to produce and lay down collagen
• Collagen is laid haphazardly in large random bundles with cross-links, after this it starts to contract and shorten up

Question 5

4. Remodelling Phase

Tissue Healing/Inflammation

Answer 5

• More collagen is laid down which increases the strength of the scar
• Tissue loading leads to fibre realignment (through functional means, may require input for excessive scarring )
• Treatment at this stage: an inadequate stretch may not achieve maximum tissue length