W1 Wound Healing

Question 1

Process of Haemostasis

Answer 1

1. Vasoconstriction
2. Platelet response
3. Biochemical response

Question 2

Aspects of vasoconstriction in haemostasis

Answer 2

• receptors on endothelium affected by serotonin and chatecholamines to vasoconstrict

Question 3

Aspects of platelet response in haemostats

Answer 3

• Damage to endothelium exposes collagen
• Platelets stick to collagen and each other
• Platelets release serotonin and prostaglandins for more vasoconstriction
• Platelets also release phospholipids and adenosine diphosphate (ADP) to attract more
• Clot made from fibrin, fibronectin, vitronectin, von Willebrand factor and thrombospondin
• Platelets attract inflammatory cells for healing by releasing cytokines, hormones and chemokines

Question 4

Aspects of biochemical response in haemostasis

Answer 4

Clot formed and destroyed through:

• intrinsic clotting pathway
• extrinsic clotting pathway
• clot retraction
• fibrinolysis

Question 5

Process of tissue repair and regeneration

Answer 5

1. Inflammation
2. Reconstruction
3. Maturation or remodelling

Question 6

Aspects of Inflammation

Answer 6

• 0-4 days

Early phase:

• capillaries contract and thrombose
• ischaemia causes histamine release for vasodilation of surrounding tissue
• influx of erythrocytes, leukocytes and plasma proteins to wound
• classic inflammatory symptoms

Late phase:

• inflammatory cells migrate to wound
• neutrophils phagocytose and kill bacteria
• monocytes bind to ECM and become tissue macrophages to: phagocytose bacteria, dead tissue and dead neutrophils