test 4 part 2

Question 1

Platelet Review

Answer 1

• Component of blood that aids in coagulation and hemostasis
• Normal platelet count: 150-450 x 103
/µl of blood
• 2 – 3 µm in diameter
• Life span: ~ 7 days
• Derived from megakaryocytes in bone marrow

Question 2

Phases of Wound Healing

Answer 2

• Inflammatory phase
• Proliferation phase
• Maturation phase

Question 3

Inflammatory Phase

Answer 3

• pain and swelling
  • Starts at time of injury and last 4 – 6 days
  • Hemostasis
  • Release of pro-inflammatory cytokines
  • Macrophages, neutrophils, fibroblasts, and damaged endothelial cells
  • Phagocytosis of bacteria by neutrophils
  • Debris removal and growth-factor secretion by macrophages

Question 4

Proliferation Phase

Answer 4

• Starts 3 - 4 days after injury and lasts 2 - 3 weeks
• Granulation tissue fills in the wound (scar)
• Fibroblast lay collagen in wound
• Development of new blood vessels (angiogenesis)
• Epithelial cells migrate from wound margins to cover wound (epithelialization)
• Wound edges begin to contract

Question 5

Maturation Phase

Answer 5

• Starts ~ 21 days after injury and last up to 2 years
• Collagen maturation and stabilization
• Increased tensile strength
• Scar-tissue formation
        • Flexibility over time
- 80% as strong as the original

Question 6

Growth Factors Released From Platelets

Answer 6

• Platelet derived growth factor (PDGF)
• Vascular endothelial growth factor (VEGF)
• Fibroblast growth factor (FGF)
• Transforming growth factor-beta (TGF-β)
• Epithelial growth factor (EGF)

Question 7

Tissue Injury picture

Answer 7

DRAW IT

Question 8

Platelet Derived Growth Factor (PDGF)

Answer 8

• Stimulates granulation tissue formation
• Stimulates epithelialization and angiogenesis
• Promotes collagen deposition
- inflammation phase

Question 9

Vascular Endothelial Growth Factor (VEGF)

Answer 9

• Promotes generation of vascular endothelial cells
• Induces angiogenesis
• Increases vascular permeability
• Stimulates tissue granulation
- Inflammation phase

Question 10

Transforming Growth Factor-Beta (TGF-β)

Answer 10

• Stimulates proliferation and migration of epithelial cells
• Promotes granulation tissue formation
• Promotes matrix formation and remodeling
• Promotes fibroblast proliferation
- affects the transition from inflammation to fibroblast proliferation

Question 11

Fibroblast Growth Factor (FGF)

Answer 11

• Promotes granulation tissue formation
• Promotes matrix deposition and remodeling
• Stimulates angiogenesis
• Promotes fibroblast proliferation
• Promotes wound contraction
- tissue granulation collagen synthesis

Question 12

Epithelial Growth Factor (EGF)

Answer 12

• Stimulates keratinocyte migration and proliferation
• Stimulates fibroblast proliferation
• Stimulates epithelial cell proliferation
• Stimulates granulation tissue formation

Question 13

Platelet Rich Plasma (PRP)

Answer 13

• Concentrated solution of platelets
• Prepared by concentrating platelets from patient’s own whole blood
  * Via a centrifugation process
• Combine with thrombin and calcium => gel

Question 14

Platelet Rich Plasma (PRP) use

Answer 14

• Clinical use of PRP is to harness the platelets and growth factors to optimize conditions for healing
• Contains 3-7 times baseline of platelets and growth factors
  * Directly at site

Question 15

Platelet Rich Plasma (PRP) Benefits

Answer 15

• Accelerates wound healing
• Decreases probability of infection
• Decreases post-op surgical adhesions
• Decreases pain
• Decreases swelling
• Minimizes scaring
• Safe and autologous
• Cost effective

Question 16

PRP Applications

Answer 16

• Chronic and non healing wound care
• Dental surgery
• Orthopedic surgery
• Plastic surgery
• Cardiac surgery

Question 17

Anticoagulant dispensing for 20 ml processing disposable (Harvest Protocol)

Answer 17

• Plasma side of processing disposable: 1 ml

- Blood Draw Syringe: 2 ml

Question 18

Anticoagulant dispensing for 60 ml processing disposable (Harvest Protocol)

Answer 18

• Plasma side of processing disposable: 2 ml

- Blood Draw Syringe: 6 ml

Question 19

Anticoagulant of choice for platelet gels

Answer 19

• anticoagulant citrate dextrose solution (ACD-A)