Lecture 24 - Cutaneous Wound Healing Flashcards
what are the layers of skin? breifly describe each
*the skin is the first 2 layers (1.5-4 mm thick)
1) Epidermis
- principle protective structure of skin (from infection and protection from other elements - ie waterproofing)
- avascular
- renews itself every 28 days
- composed of epithelial cells
2) Dermis
- composed of loose connective tissue allowing blood vessels and sensory nerve endings to pass through.
- supports and nourishes the epidermis
- nerves, hair follicles, sebaceous glands and sweat glands
3) Subcutaneous Layer
- Constist of an energy reserve (subcutaneous fat)
- Role: thermal protection; shock absorption – protection
- Contains: Pacini corpuscles and other mechanoreceptors
what is Hyperkeratosis?
abnormal thickening (hyperplasia) of the «stratum corneum» found on the epidermis of a person with diabetes
what is Granulation tissue?
tissue formation, red, raspberry-like in appearance, includes small blood vessels and collagen fibers. Granulation tissue acts as a support that allows migration of the epithelial cells in the epidermis and covering of the wound.
what is Maceration?
overabundance of humidity in the tissues (whitened skin)
what is Fibrin?
thin yellowish layer, deposit found on the surface of the wound during the inflammatory phase (globulin, filament-like insoluble, white and elastic, contains deposits as a result of spontaneous blood coagulation, lymph and certain exudates. The filaments form a network that includes knots containing platelet aggregates.)
what is Necrotic tissue/slough/cangrenous?
dead tissue that are yellow, grey, blackish or greenish in appearance.
what is Eschar?
black, hard crust (scar) resulting from necrosis of a cutaneous or mucous covering
what is Erythema?
redness found on skin covering (integument) more or less intense disappearing with pressure.
what is Undermining?
area where the skin thickness is detached from the tissues below.
what is sinus tract?
deep, formed anatomical tunnel
describe partial thickness wounds
Note: there are remaining sebatious glands bc its a partial thickness wound and therefore these islands come and it heals faster - this cannot occur in a full-thickness wound and therefore it takes longer to heal
describe full thickness wound healing
describe the 4 stages of wound healing
Phase I: Hemostasis
- Stopping of bleeding / coagulation
- Accumulation of platelets & fibrin: «fibrin clot»
Phase II: Inflammatory
- Inflammatory response: redness, edema, warmth, pain, ↓ range of motion
- ↑ blood vessel permeability→ plasma leaks into the interstitial space → oedema
• Autogenic debridement: process through which the body uses its own mechanisms to remove dead tissue.
N.B. A humid environnement is required
• Infection control through white blood cells (leukocytes): neutrophil, macrophages, lymphocytes
Phase III : Proliferation (fibroblastic)
• Repair (healing) through enhanced cellular activity.
• Forming of granulation tissue:
– Angiogenesis:newbloodvesselsforemdviaendothelialcells. – Collagen/extra-cellularmatrix:viathefibroblasts
• Closing of the wound by granular tissue contraction (myofibroblasts) and by epithelialisation (mitosis of the epithelial cells)
Phase IV : Remodeling (maturation)
• Collagen fibers organize themselves, increase their elasticity and resistance to traction in order to regain the consistency/ configuration of healthy tissue.
the 4 stages of acute wound healing and cells involved timeline
what classifies a chronic wound?
Chronic wound:
- One that deviates from the expected sequence of repair in terms of time, appearance and response to aggressive and appropriate treatment.
- 4to12weeksand+
what are the 4 types of chronic wounds?
! Pressure ulcers ! Venous ulcers ! Arterial ulcers ! Neuropathic ulcers
descibe the pathophysiology of pressure ulcers
Localized areas of tissue necrosis that tend to develop when soft tissue is compressed between a bony prominence and an external surface for a prolonged pediod of time
describe a stage 1 pressure ulcer
describe a stage 2 pressure ulcer
describe a stage 3 pressure ulcer
describe a stage 4 pressure ulcer
describe pressure sore classification/characteristics
Stage – Unspecified
- Complete tissue loss whereby the bed of the wound is covered by humid, necrotic tissue or eschar.
- Unable to determine the stage of the pressure sore until the necrotic tissue or the eschar is debrided to see the bed of the wound.
what is the pathophysiology of venous ulcers?
- Muscle contraction (calf muscle) pumps blood and enhances venous return.
- Unidirectional valves prevent blood from flowing back.
- Venous hypertension can occur when there is insufficiency of the valves.
cause of venous hypertension
characteristics of venous ulcers
arterial ulcers - pathophysiology
arterial ulcers - predisposing factors
characteristics of arterial ulcers
pathophysiology of neuropathic ulcers
describe sensory neruopathy
describe motor neuropathy
describe autonomic neuropathy
characteristics of neuropathic ulcers
what is the classification of infection for chronic wounds?
what are the signs and symptoms of systemic, topical, and local infections?
describe how to assess a wound
1) measure wound height, width, and depth (include depth of neighbouring spaces and and sinuses)
2) trace the area of the wound (use clock technique)
3) pressure sensativity assessment (Pt at risk of developing a diabetic ulcer if feels < 8/10 points)
4) vascular assessment
- Skin temperature
- Discolouration during incline & capillary refill -Pulses
- Ankle brachial pressure index (ABI)
- Toe pressure (IPOB)
-Doppler ultrasound (vascular)
* slides 61-78
optimal conservative management
describe local wound care
describe “treat the cause” for optimal conservative management
describe patient centred concerns for optimal wound healing
indications for debridement
contra-indications for debridement
• Insufficient blood flow (wound not healing and no potentila to do so):
- Arterial Insufficiency (IPTB<0,5)
- Dry gangrene
- Stable eschar stable on the heels (dry, adherent, intact, completely closed, no redness or liquid fluctuations) acts as a natural protective layer & should not be removed
- Autolytic debridement with an non breathable dressing on an infected wound.
- Presence of metal composites – part of an enzymatic debridement (if removed they inactivate the Collagenese Santyl)
precautions for debridement
Should we debride fibrin?
Fibrin has 3 roles:
– Partially retains fluides
– Protects underlying cells from dessication.
– Provides subtances for coagulation
Optimal dressings to maintain a balanced hydration
• Maintain the bed of the wound humid & the epidermis around the edges dry
Done by controlling amount of exudate via choice of dressings or product.
Need to avoid saturation (too humid) & dessication of the wound & surrounding tissues.
what are sterile techniques - sterile vs clean environment?
Goal:
-prevent infection & contamination of the wound -prevent contamination of the environment
Principles:
- rigourous hand washing before donning gloves & when removing -«Everything that touches the wound must be sterile»
- As soon as a clean and sterile object touches a non-sterile surface, the object is potentially contaminated and becomes non-sterile.
- Be aware of cross-contamination
- Dispose of contaminated material is specific bags.
-Clean & disinfect meticulously any instruments that will be reused according to the institutional policy.
describe reduction weight bearing conservative management
slides 92-99
Preventive=40-70 mmHg
Curative=<32 mmHg
darco vs walking boot
what are the types of compression therapies?
- Pneumatic compression pump (ICP)
- Bandages
- Elastic (high compression)
- Non-elastic (low compression)
• Stockings
what are the physiologic effects of compression? when are they indicated?
• Restoration of venous return
- Reduction of tissue edema
- Improved tissue perfusion
Indication:
“Compression is the mainstay of treatment of venous ulcers”
contra-indications for compression therapies
- Thrombophlebitis (& 2 sem. post)
- Localized infection (osteomyelitis)
- Arterial insufficiency according to ABI (refer: table)
- Pressure hypersensitivity (local)
- Pulmonary embolism/edema
- Congestive heart failure
- DVT (deep vein thrombosis)
describe ICP application and parameters
• Recordpretreatmentlegedema(girth,legvolume)
Application:
- Cover wound in absorptive clean dressing
- Plastic filmas needed to prevent exudate from contaminating the pump sleeve
- Cover leg with cotton sleeve (stockinette)
- Apply pump sleeve
- Place limb in elevated position
- Post treatment:
- Remeasure limb for edema
- Apply compression bandage/stocking
describe compressive bandages
Particularities
- The inelastic bandages are usually better tolerated in the presence of pain.
- In the presence of lymphedema the inelastic dressings are preferable.
describe compressive stockings
describe Level of compression vs ABI
describe Whirlpool water temperatures in wound care:
what is the hydrotherapy Treatment duration for diff wound types?
hydrotherapy indications
hydrotherapy contraindications
- Clean wound
- Severe arterial insufficiency(ABI<0,5),dry gangrene
- Deep venous thrombosis
- Sensory impairment(discriminationhot/cold)
- Severe edema(lymphedema)
- Maceration tissue
- Hemophilia, high INR, increased risk of bleeding
- Medically unstable(febrile,syst.cardio-vasc.)
- Skin cancer
- Pregnancy (1er trimester)
- Severecognitivedeficit/severementalhealthproblem
hydrotherapy precautions
hydrotherapy consideratoins during application
- Do not remove the dressing in the whirlpool bath
- Before the treatment, clean & disinfect the intact skin of the
submerged limb (90 secs contact) & if possible, irrigate the wound (decrease contamination)
- As possible avoid placing two limbs in the same whirlpool bath to avoid contamination between wounds.
- Do not direct the water jet directly on the wound. (This increase transfer of heat and penetration of bacteria)
- Therapist is exposed to contaminants in the water or via droplets. Should be appropriately dressed for infection control: eg: gown, gloves, mask, glasses
- Encourage active movement of the limb during hydrotherapy session ( increase range of motion, decrease edema)
- Rinse the wound for at least 10 secs after the treatment (decontamination)
- Not necessary to use antiseptic agent during the treatment as it can be cytotoxic for fibroblasts.
- Meticulous disinfection of the bath after each treatment.
- Open wound, infected or not: beware of cross-contamination
- Neutro-hydrotherapy: recommended for patients with mld to severe thermoregulation difficulties, eg: children, elderly)
- Mental & physical health status: will determine level of supervision required/risk of fainting/drowning
wound evaluation soapie format and clinical impression
- see required reading doc
