Wound Healing. W1
What are the factors affecting wound healing?
-General -Local -Systemic -Clinician
What are they key events occurring during the proliferation phase of wound healing?
1. Angiogenesis: formation of new blood vessels 2. Granulation tissue: Fribroblast lay down extracellular matrix (eventually replaced by scar tissue) 3. Wound Contraction- myofribroblast pull wound margins together 4. Epithellization-keratinocytes and epidermal appendages multiply and migrate accross wound bed
What happens during the cellular response of the inflammation phase?
1. Margination: Increased leakiness of vessel walls pushing PMNs to the sides of vessels walls PMNs: 1st to arrive to the site of injury (12-24 hrs)-degrade debris 2. macrophages arrive: kill pathogens, direct repair process 3. Mast cells: produce histamines and secrete enzymes to accelerate riddance of damage cells
What are some general factors affecting the wound healing?
1. Mechanism of Onset. Etiology 2. Time since onset - Acute vs Chronic 3. Location- consider blood supply, bony prominences, typical skin thickness. Thin skin heals quicker 4. Wound Dimensions- Circular is slower than square (slower than rectangular) or rectangle is slower than linear 5. Temperature (37-38 degrees C is best) 6. Wound Hydration 7. Necrotic tissue 8. Infection
What are the key cells involved in the cellular response during the inflammatory phase?
1. Platelets 2. PMNs 3. Macrophages 4. Mast cells
What does the vascular response consist of during the inflammation phase?
1. Transudate leaks out of vessels: local edema 2. Local blood vessels reflexively constrict 3. Platelets aggregate and are activated. A plug is formed closing the lymphatic channels and creating more edema and releasing chemical mediators for wound healing. 4. W/in 30 mins of vasocontriction, vasodilation occurs: localized redness, warmth, edema
What are some inappropriate wound care factors caused by clinicians?
Prolonged or inappropriate use of antiseptics • Wrong dressing selection (macerates or dries out) • Failure to detect/treat infection • Inappropriate irrigation, debridement, compression, etc. • Poor wound exploration • Poor temperature management
What are the phases of wound healing?
1. inflammatory phase 2. proliferative phase 3. maturation/remodeling phase
arrange from fastest to slowest the healing of wounds according to their shape
1. linear 2. rectangular 3. Square 4. Circular
What are the cardinal signs of the vascular response of the inflammation phase?
1.Edema 2. Redness 3. Warmth 4. Pain 5. Decreased function
Smoking cessation is an important component of wound healing, what is the percentage of tissue oxidation increase after just 46 hours of not smoking?
10% higher
What are the systemic factors related to aging affecting the wound healing?
Age: normal physiologic changes • Slowed immune response • Decreased collagen synthesis • Epidermal and dermal atrophy (thinner skin) • Less sweat and oil glands (dryer skin) • Decreased pain perception • Decreased inflammatory response • More co-morbidities • More susceptible to infection • More medications
What are the systemic factors related to nutrition affecting the wound healing?
Amount of carbs consumed, needed for energy Amount of proteins consumed, needed for cellular repair/regeneration
What are the key cells involved in the proliferation phase?
Angioblast Fibroblast Myofibroblast Keratinocytes
What happens during the maturation phase of healing?
Granulation tissue must be strengthen and reorganized Rapid collagen synthesis Up to 2 years following the wound closure. Greatest change in 1st 6 to 12 months 80% of full tissue strength Unable to sweat-loss of sweat glands less sensitive to touch and temperature
What are the cell types to arrive first at an injury site?
PMNS
Tpe of precautions for Cdiff and MRSA
contact
Type of precautions for influenza and whooping cough
droplets
What are some local factors affecting the wound healing
• Circulation: Macro and Micro Sympathetic nervous system responses to: cold, fear, and pain • Sensation Decreased knowledge of pain Additional trauma to area • Mechanical Stress Friction, shear, weight bearing, pressure,
What are the systemic factors related to comobidities affecting the wound healing?
• Those affecting O2 perfusion: PVD, anemia, COPD, heart conditions • Immunocompromised: HIV/AIDS, diabetes • Activity limitations
Type of precautions for TB and chicken pox
airborne
TRUE OR FALSE. It is appropriate to apply an enzymatic debrider such as Santyl into an infected wound.
TRUE
What happens during the inflammation phase, what's the main goal?
Vascular response and cellular response To control bleeding, fight infectious agents.
How are some ways that clinicians can appropriately care for wounds?
Appropriate Wound Care • Initial use of antiseptics to kill everything • Maintenance care when wound healing is not priority. may have bigger things going on. • Use of iodine to encourage/maintain non-viable tissue desiccation
What are some behaviors that can affect wound healing?
Smoking: decreases tissue perfusion and oxygenation There is a decrease of 30% of O2 concentration after smoking ETOH: Increases the risk of injury due to malnutrition and impair judgement
What are the systemic factors related to medications affecting the wound healing?
Steroids Chemtherapy NSAIDS