wound healing Flashcards
superficial wounds: skin tears
confined to layers of epidermis and dermis
will heal by re-epithelialization
wounds extending past the dermis heal by:
scar formation
3 types of wound healing:
primary intention
secondary intention
tertiary intention
primary intention:
wounds that have been surgically closed or approximated with sutures or staples
secondary intention:
wounds that have been left open and allowed to heal through scar tissue formation
tertiary intention:
delayed primary closure
occurs when wound is intentionally left open for a period of time and then closed surgically at a later date
often necessary in cases where there is a wound infection that needs to be treated before surgical closure
wounds that fall into category of healing by secondary intention:
pressure
venous
arterial
diabetic
neuropathic
trajectory of wound healing:
process of how wounds extending beyond the dermis heal once there is tissue damage
visualized as:
1) hemostasis
2) inflammation
3) proliferation
4) remodeling
4 phases are over-lapping = each phase must be completed in order for the wound to close
wound healing relies on:
sequential cascade of cellular and biomechanical events
if trajectory is interrupted at any point, the wound will not close
hemostasis:
body’s immediate response to any type of tissue injury
vasoconstriction occurs and platelets aggregate in injured area to initiate blood coagulation
result = formation of fibrin clot = seals of injured vessels so blood loss is controlled
calcium and vitamin K = important in clot formation
after clot forms = it contracts = starts to pull wound edges in
failure to clot: factors
medications (anti-coagulants)
recent lab reports (low platelet counts)
inflammatory:
occurs once bleeding is controlled
can last up to 4 days
focus = establish a clean wound bed
neutrophils, macrophages, and lymphocytes enter wound bed and begin phagocytosis of bacteria and damaged tissue
increased erythema, induration, heat, and pain
things that delay/impair inflammatory process:
steroid medication
diabetes mellitus
HIV
chemotherapy
necrotic tissue in wound bed
foreign bodies (sutures/staples)
wound infection
advanced age
repeated pressure or trauma
impaired immune reponses =
mask traditional signs of infection and inflammation
until these factors are treated or removed, they will continue to delay healing
proliferation:
growth of granulation tissue filling in the wound cavity
neoangiogenesis = development of new capillaries
once wound has started filling in = edges begin to contract = wound begins to epithelialize
new epithelial cells branch from edges of wound by joining with small islands of epithelialized tissue in wound bed until it resurfaced the entire wound
starts 4th day of tissue damage and lasts up to 21 days
poor nutrition:
can prolong proliferation phase of healing
growth of new granulation tissue and blood vessels is delayed
wounds healed without optimal nutrition = weak = likely to break down again
remodelling/maturation:
last and longest phase of wound healing
starts after wound closure - lasts up to 2 years
additional collagen is laid down in the wound and reorganized to increase tensile strength
edges of wound contract/draw together = decreasing size of defect
restructuring and realigning of tissue = increase its tensile strength
changes color of scar from dusty red to pale pink or white
closed vs healed
when epithelialization is completed the wound is considered closed rather than healed
closed wound is still weak and vulnerable to re-injury
even when remodeling is completed and wound is considered healed - scar tissue is only about 80% as strong as original skin
healed wound is always at higher risk of injury
timeline for trajectory of wound healing:
hemostasis: immediate
inflammation: 0-4
proliferation: 4-21
remodeling: 21- 2 years
A venous ulcer has been present for four weeks. Mrs.Applewood has had vascular testing to indicate there is enough arterial blood supply to support wound healing. She eats well, is active, and does not smoke.
This wound is in the ____ phase of wound healing as there is presence of necrotic tissue
inflammatory
A venous ulcer has been present for four weeks. Mrs.Applewood has had vascular testing to indicate there is enough arterial blood supply to support wound healing. She eats well, is active, and does not smoke.
It is healing by:
secondary intention
A venous ulcer has been present for four weeks. Mrs.Applewood has had vascular testing to indicate there is enough arterial blood supply to support wound healing. She eats well, is active, and does not smoke.
Increased pain and erythema are signs of wound infection. Will the wound progress to the next phase of wound healing while there is infection present?
No
A stage 4 pressure ulcer (went to bone) over a coccyx. Without conservative wound management, it took 10 weeks to close to this present state.
This wound is completely closed and is in the ___ phase of wound healing trajectory.
remodeling/maturation
A stage 4 pressure ulcer (went to bone) over a coccyx. Without conservative wound management, it took 10 weeks to close to this present state.
True or false: We still protect this area after is has closed over with epithelial tissue as extra collagen is deposited in the affected area during this phase.
True
collagen deposition helps increase tensile strength of tissue, however the resulting scar will never be as strong as the undamaged skin prior to injury
area = at higher risk of re-injury
A stage 4 pressure ulcer (went to bone) over a coccyx. Without conservative wound management, it took 10 weeks to close to this present state.
True or false: In this final phase, vascularity of the tissue is decreased and there is contracture of the scar.
True
decreased vascularity leads to a color change in the scar from dusky red to pale pink or white
contraction decreases the overall size of the scar
When the wound was open and needed dressing changes, part of the care plan was to ensure the patient did not lie on his back for any great period of time and instead alternated lying side to side. Though the wound has now closed over, the health care team decides to keep this plan in place. They slowly increase the time spent on his back but closely monitor it for any new areas of tissue damage.
A few days later, you notice tissue damage has occurred to this same area. The wound presents with yellow necrotic tissue, erythema and increased pain. This wound is now in the ___ phase.
inflammatory
