Wound Healing Flashcards
Describe the body’s defense in would healing.
- Stop the blood loss.
- Clean up pathogens.
- Seal wound against infection.
- Regenerate natural epidermal covering.
- Repair deeper tissue damage.
What are the main phases of healing?
- Inflammation
- Proliferation
- Remodeling
What happens during the inflammation phase?
- hemostasis
- phagocytosis
- edema
Up to 7 Days
What happens during the proliferation phase?
- Epithelization
- Neovascularization
- Collagen synthesis
- Contraction
Up to 20 Days
What happens during remodeling?
- Tensile strength
- Collagen remodeling
Up to 2 Years
How soon does hemostasis begin?
0 to 2 hours, as soon as the incision is made.
Hemostasis occurs ______.
Within seconds, by vasoconstriction. Platelets aggregate to form a clot.
How soon does phagocytosis happen?
0-4 days. Wound is red and swollen.
How soon does Edema occur?
0-6 days
What does the wound look like when phagocytosis occurs?
Wound is red and swollen.
Phagocytosis occurs when…
Phagocytosis occurs when neutrophils and macrophages appear to digest and dispose of pathogens and debris.
What happens during edema?
Capillary walls become permeable to plasma. Plasma leaks into wound, causing edema.
Proliferation phase starts _____ and continues until ____.
Proliferation starts the second day after incision and continues until 22nd day.
What are the events in proliferation?
Epithelialization
Neovascularization
Collagen Synthesis
Contraction
When does epithelialization occur?
1 to 4 days
What happens during epithelialization?
Fibroblasts migrate toward the wound site. Keratinocytes begin the formation of a scab sealing of the wound.
When does neovascularization occur?
2-7 days
The time period when most wound disruptions occur?
Neovascularization.
When does collagen synthesis happen?
2 to 22 days.
What is contraction?
Contraction is caused by fibroblasts transforming into myofibroblasts. Myofibroblasts help strengthen the wound and close any remaining defects.
What are the elements in the remodeling phase?
collagen remodeling
tensile strength gain
The remodeling phase starts ____ days after incision and may continue for ____
The remodeling phase starts 21 days after the incision and may continue for 2 years.
What is tensile strength gain?
Scar tissue remodels.
What are the three ways in which wounds heal?
- Primary union or first intention
- Granulation or second intention.
- Delayed primary closure or third intention.
What are examples primary or first intention?
surgical incision, simple laceration; minimal tissue damage; no postop complications
What are examples of granulation or second intention?
infected wounds, drains, trauma, tissue loss; significant tissue loss and may require tissue grafting. Wound is left open and allowed to heal from inner to outer surface.
What are examples of delayed primary closure or third intention?
compartment syndrome, burns, debriedement, wound disruption, excessive trauma; wound is kept open, gauze packing
What are characteristics of class I, clean wounds?
- no inflammation
- no breaks in sterile technique.
- No hollow, viscous entered.
- Respiratory alimentary, genital, or infected urinary tracts are not entered.
What are characteristics of class II, clean contaminated wounds?
- nontraumatic wounds
- no inflammation
- no breaks
- hollow viscous entered
- Respiratory, alimentary, genital, or urinary tracts are entered under controlled conditions.
What are characteristics of class III, contaminated wounds?
- open, fresh, accidental wounds
- major break in technique occured
- entrance into genitourinary or biliary tracts with infection.
What are characteristics of dirty or infected wounds?
- old wounds with retained devitalized tissue.
- Perforated vicera
- Chronic, infected wounds
Pre-op factors affecting wound healing?
Inadequate nutrition physical conditions medication/age pre-op skin prep pre-op stress existing infections
Intra-op wound factors?
length of surgery location of the wound complications foreign bodies in the wound Elimination of dead space in the wound Unplanned periop hypothermia
how do steroids affect wound healing?
decreases inflammatory response
How do anti-coag meds affect wound healing?
Affects hemostasis
How do chemo meds affect wound healing?
decreases protein synthesis
How does radiation affect wound healing?
decreases blood supply and increases scarring
Factors affecting wound healing, controlled by the surgical team
hypothermia
stress and immobilization on the wound
closure material
aseptic technique
What nutritional component assists in collagen production and capillary formation?
Vitamin C
How does stress affect wound healing?
Stress elevates glucocorticoid levels which inhibit wound repair and weakens tissue under repair.
Always clean open wounds with
Sterile water
What are the four methods of hemostasis?
- Passive
- Active
- Flowables
- Fibrin Sealants
What are the four types of passive hemostatic agents?
- Cellulose
- Collagens
- Gelatins
- Polysaccharide spheres
(surgicel, surgifoam)
What do passive hemostatic agents do?
Applied at the bleeding site and provides a barrier to stop blood flow.
What do active hemostatic agents do? What’s an example of it?
These contain thrombin and enhance the clotting cascade. (THROMBIN).
What do flowable agents do? What’s an example of it?
Combination of active and passive. Mechanically obstructs blood flow. Converts fibrinogen into fibrin at the bleeding site.
Does not contain fibrinogen, and requires direct contact with blood to work.
(FLOSEAL)
What are fibrin sealants and what’s an example of it?
Promotes blood clotting by increasing fibrinogen and thrombin at the bleeding site. (TISSEEL).
What are the intraop wound factors?
- Length of surgery
- Location of wound
- Complications
- Foreign bodies
- Dead space
