54 chronic wound healing (Hansen)

•Tunneling

-extends in any direction (but one way) from wound surface or edge and results in dead space with potential for abscess formation. One wound can have several tunnels.

Permanent cells

CNS nerves -cannot be replaced

Stable cells

Cells that do not regularly undergo mitosis but are able to if the need arises -bones, glands, muscle

Labile cells

Cells that undergo mitosis regularly and quickly Examples -RBCs -mucus membranes

why does renal failure affect healing?

because the homrone in kidneys for RBC production is affected slowing down healing -H & H are low

Regeneration

top layer of skin

•Undermining

- perpendicular to wound; involves large area; along wound periphery

•Dry gangrene

-arterial -no blood supply -have to be amputated

•Gas gangrene

-clostridium -creates bubbles in tissue

venous

-medial ankle area "gator area" -irregular boarders -lift leg -can use a warp -can feel pulse

Vacuum Assisted Closure-Wound Vac

-used for bad infections -help heal faster

arterial

-usually toes and fingers, heals, smaller or circular -pale -no hair -do not lift leg -no wrap -can't feel pulse -we can't really do much to fix the issue

•Wet gangrene (staph, strep usually)

-venous -more likely to get systemic -venous constriction

What causes a chronic wound?

1. absence of hemostasis (healing is initiated by clot breakdown and release of growth factors) 2. prolonged inflammatory (heavily infected will get stuck here until bacterial load controlled or dead tissue removed). Impaired inflammatory (e.g. steroids) 3. prolonged proliferative phase (bigger wound = more granulation) 4. decreased contraction (rate of contraction is 0.6 to 0.7 mm/d) 5. delayed epithelialization (epidermal appendages missing) 6. prolonged remodeling

▫RBC's

= 120 days

▫Albumin

= 21 days; prealbumin ~4 days

•Necrosis

= cell death (not reversible) ▫Coagulative necrosis-most common ▫Liquefactive necrosis-brain ▫Caseous -looks like clumped cheese; combination of coagulative and liquefactive. Seen in TB. ▫Fat necrosis- death of adipose tissue; opaque chalk-white tissue; seen in pancreas

▫Epithelial cells

= continual

•Apoptosis

= programmed cell death ▫RBC's = 120 days ▫Albumin = 21 days; prealbumin ~4 days ▫Epithelial cells = continual

Factors affecting healing

Intrinsic factors ▫age: decreased inflammatory response; delayed angiogenesis; decreased collagen synthesis and degradation-- wound contraction is slowed so greater risk of dehiscence; slower epithelization; decreased cohesion between epidermal and dermal layers; decreased function of sebaceous glands (dry skin). ▫Chronic diseases Diabetes mellitus—get blood sugar down!!! Renal failure Cardiac ▫Perfusion and oxygenation ▫Immunosuppression ▫Neurologic impairment of skin ▫Nutritional status; obesity ▫Clotting factors •Extrinsic factors ▫Medications ▫Irradiation (severely damages skin and tissue) and chemotherapy ▫Psychological stress (noise, pain, temperature, lack of sleep, other stressors that initiate release of vasoactive substances) ▫Smoking ▫Wound trauma ▫Improper dressings

keloids

Nodules formed in wound healing due to excessive collagen

Necrotic fatty tissue

Seen in fatty tissue (breast, thigh) and pancreas.

•Fistula:

an abnormal passage between two or more body organs or spaces

▫Bone: predictable series of events

Stage I or fracture hematoma stage (=Phase 1) Stage II or fibrocartilage formation (=Phase 2) Stage III or callus formation (=Phase 2) Stage IV or ossification (=Phase 2 and 3) Stage V or consolidation and remodeling (Phase 3)

fistula

abnormal passageway between two organs or between an internal organ and the body surface -Inflammatory tract that connects two hollow organs or a hollow organ with the skin.

Sinus tract:

connects abscess to skin; similar to tunneling but used in relation to abscess

Granulation tissue with little epithelial tissue picture

healing through secondary

peripheral nerve tissue picture

if intact can regenerate

▫Coagulative necrosis-most common found in

in organs like heart and adrenal glands and kidneys

Allograph

is from another human donor.

Xenograph

is from different species (cow, pig, etc).

Apligraph

is from neonate.

Autograph

is from same individual.

•Abscess:

localized, encapsulated collection of pus

Repair

tissue is replaced but doesn't have the same properties as the original tissue did -making a scar so doesnt have sweat glands or hair -structurally its the same p to 80%

Healing of deep structures

•1. Cell types ▫Labile ▫Stable ▫Permanent •Process of healing in different structures ▫Liver: depends if underlying framework is intact Healing following hepatitis A differs from healing following Hepatitis C; alcohol effects on liver

Gangrene

•A complication of necrosis. Seen in extremities due to anoxia; also seen in bowel Necrosis is a type of cell injury where premature death of cell occurs. Gangrene is a life threatening condition which arises when a considerable mass of living healthy tissue dies. Gangrene is one of the clinical manifestations of necrosis. Necrosis pertains to cellular level, whereas gangrene involves the tissues.

Problems in the inflammatory phase (Abnormal healing)

•Abscess •Fistula •Tunneling: unidirectional; does not necessarily end in an abscess •Undermining

other issues when healing

•Dehiscence •Evisceration •Herniation •Contractures/strictures •Adhesions •Aneurysm

Problems in Proliferative stage

•Granuloma (a mass of granulation tissue, typically produced in response to infection, inflammation, or the presence of a foreign substance. •Ulcer •Fibrinous exudate

Problems in the reconstructive and /or remodeling phase

•Hypertropic scarring •keloids •Dehiscence •Evisceration •Herniation •Contractures/strictures •Adhesions •Aneurysm

chronic wounds you will encounter

•Pressure injuries •Leg ulcers ▫Arterial ▫Venous ▫Diabetic foot ulcers

•1. Cell types

▫Labile ▫Stable ▫Permanent

•Process of healing in different structures

▫Liver: depends if underlying framework is intact Healing following hepatitis A differs from healing following Hepatitis C; alcohol effects on liver

•Extrinsic factors affecting healing

▫Medications ▫Irradiation (severely damages skin and tissue) and chemotherapy ▫Psychological stress (noise, pain, temperature, lack of sleep, other stressors that initiate release of vasoactive substances) ▫Smoking ▫Wound trauma ▫Improper dressings

Regeneration examples

▫Muscle ▫Ligaments sprain ▫Tendons strain ▫Peripheral nerves ▫Central nerves ▫Vascular endothelium ▫Heart

Intrinsic factors affecting healing

▫age: decreased inflammatory response; delayed angiogenesis; decreased collagen synthesis and degradation-- wound contraction is slowed so greater risk of dehiscence; slower epithelization; decreased cohesion between epidermal and dermal layers; decreased function of sebaceous glands (dry skin).