Wound care exam 1
how often is the outer layer of the skin replaced?
every 28 days
skin physiology
protective barrier from micro-organisms, conservation of fluid, protein and
electrolyte loss, regulation of body temperature, secretory ability (sweat and
serum), vitamin D production, sensation, appearance and self-image, wound
healing and epithelial cell regeneration
2 layers of the skin
epidermis and dermis
epidermis
avascular layer (paper cut that doesn't bleed= epidermal), varies in thickness
in different body areas (thicker in greater pressure areas such as palms and
heels)
dermis
vascular layer
2 areas:
-papillary: upper layer that connects epidermis to dermis, ridges gives us
fingerprints
-reticular: between papillary and subcutaneous tissue, small blood vessels
here supply blood to hair follicles and sweat glands
supports epidermis through tensile strength (collagen) and elasticity (elastin)
sebaceous glands
secretes sebum (oil) from hair follicle through hair shaft to keep skin moist,
sebum is acidic (antibacterial)
,sudoriferous glands
produces sweat for cooling and eliminates waste products
transdermal medications
drug applied directly to the skin so it can be absorbed through the dermal
layers and into subcutaneous tissue for peripheral circulation. provides slow,
controlled release and drug stays at a constant level in blood for prolonged
period of time
types: patch, implants placed under the skin, creams
benefit is drug avoids degradation in the GI tract or liver so effective delivery
system for drugs with a short half-life, but must also be able to penetrate the
skin
medication is applied to clean, dry, hairless skin with no rash or irritation and
with good circulation. avoid areas with high friction (ex: waistline)
contusion
a region of injured skin in which blood capillaries have ruptured
ecchymosis
blueish discoloration resulting from bleeding in the subcutaneous tissue (seen
on patients on steroids)
purpura
also called blood spots or skin hemorrhages. occurs when small blood vessels
burst, causing blood to pool under the skin
abrasion
injury in which the top layer of skin has been removed due to motion against a
rough surface
laceration
,a deep cut or tear in the skin
primary intention wound closure
surgical incision or acute injury that is closed via sutures, staples, glue or skin
grafts
primarily heals by reepithelialization
negative outcome would be a wound that later re-opens (dehisence), often
from infection
secondary intention
wounds that are left open to heal
tertiary intention
surgical incision left open a few days (3-7) and then closed with sutures, often
seen when there is a higher risk for infection
superficial wounds
ex: first degree burn (sun burn), loss of the epidermis
partial thickness wound
ex: abrasions, skin tears, 2nd degree burns
closes by re-epithelialization
re-epithelialization
epithelial cells resurface to protect itself from invasion of microorganisms
cells travel in a sheet to resurface, moist environment speeds up resurfacing
project, goal is wound closure
full thickness wound
loss of all layers of the epidermis, dermis, and subcutaneous tissue
closes by contraction and scar tissue formation-> scar tissue has less
elasticity and tensile strength than original tissue
, phases of healing
inflammatory-> proliferative-> maturation
# of days spent in each phase varies based on several factors: age, size of
wound,, co-morbidities, continued trauma,, nutrition blood flow medications,
stress and infection
inflammatory phase of wound healing
starts moment of injury and lasts 3-10 days
chronic inflammation can cause wound to get stuck in this phase (associated
with necrotic tissue, hematoma or infection)
goal: hemostasis and produce clean wound
coagulation cascade
first step of inflammatory phase
immediate clotting and vasoconstriction to decrease blood loss, platelets
arrive and form a fibrin clot, platelets signal growth factors, histamine causes
vasodilation and delivery of leukocytes, increased vascular permeability also
delivers leukocytes
patients taking anticoagulation drugs will have problems with this phase
white blood cells
neutrophils arrive first and kill debris and remove dead tissue-> pus
(purulence) is a lot of dead neutrophils that have phagocytized debris
macrophages arrive later and are key in the transition from inflammatory to
proliferative phase: secrete collagenase which debrides dead tissue, initiate
angiogenesis and granulation (scar tissue) formation
proliferative phase of healing
begins 3 days post injury and continues for at least 3 weeks. goals: fill-in and
close wound
processes involved: angiogenesis, collagen synthesis, and contraction
macrophages and neutrophils continue to work to control infection
how often is the outer layer of the skin replaced?
every 28 days
skin physiology
protective barrier from micro-organisms, conservation of fluid, protein and
electrolyte loss, regulation of body temperature, secretory ability (sweat and
serum), vitamin D production, sensation, appearance and self-image, wound
healing and epithelial cell regeneration
2 layers of the skin
epidermis and dermis
epidermis
avascular layer (paper cut that doesn't bleed= epidermal), varies in thickness
in different body areas (thicker in greater pressure areas such as palms and
heels)
dermis
vascular layer
2 areas:
-papillary: upper layer that connects epidermis to dermis, ridges gives us
fingerprints
-reticular: between papillary and subcutaneous tissue, small blood vessels
here supply blood to hair follicles and sweat glands
supports epidermis through tensile strength (collagen) and elasticity (elastin)
sebaceous glands
secretes sebum (oil) from hair follicle through hair shaft to keep skin moist,
sebum is acidic (antibacterial)
,sudoriferous glands
produces sweat for cooling and eliminates waste products
transdermal medications
drug applied directly to the skin so it can be absorbed through the dermal
layers and into subcutaneous tissue for peripheral circulation. provides slow,
controlled release and drug stays at a constant level in blood for prolonged
period of time
types: patch, implants placed under the skin, creams
benefit is drug avoids degradation in the GI tract or liver so effective delivery
system for drugs with a short half-life, but must also be able to penetrate the
skin
medication is applied to clean, dry, hairless skin with no rash or irritation and
with good circulation. avoid areas with high friction (ex: waistline)
contusion
a region of injured skin in which blood capillaries have ruptured
ecchymosis
blueish discoloration resulting from bleeding in the subcutaneous tissue (seen
on patients on steroids)
purpura
also called blood spots or skin hemorrhages. occurs when small blood vessels
burst, causing blood to pool under the skin
abrasion
injury in which the top layer of skin has been removed due to motion against a
rough surface
laceration
,a deep cut or tear in the skin
primary intention wound closure
surgical incision or acute injury that is closed via sutures, staples, glue or skin
grafts
primarily heals by reepithelialization
negative outcome would be a wound that later re-opens (dehisence), often
from infection
secondary intention
wounds that are left open to heal
tertiary intention
surgical incision left open a few days (3-7) and then closed with sutures, often
seen when there is a higher risk for infection
superficial wounds
ex: first degree burn (sun burn), loss of the epidermis
partial thickness wound
ex: abrasions, skin tears, 2nd degree burns
closes by re-epithelialization
re-epithelialization
epithelial cells resurface to protect itself from invasion of microorganisms
cells travel in a sheet to resurface, moist environment speeds up resurfacing
project, goal is wound closure
full thickness wound
loss of all layers of the epidermis, dermis, and subcutaneous tissue
closes by contraction and scar tissue formation-> scar tissue has less
elasticity and tensile strength than original tissue
, phases of healing
inflammatory-> proliferative-> maturation
# of days spent in each phase varies based on several factors: age, size of
wound,, co-morbidities, continued trauma,, nutrition blood flow medications,
stress and infection
inflammatory phase of wound healing
starts moment of injury and lasts 3-10 days
chronic inflammation can cause wound to get stuck in this phase (associated
with necrotic tissue, hematoma or infection)
goal: hemostasis and produce clean wound
coagulation cascade
first step of inflammatory phase
immediate clotting and vasoconstriction to decrease blood loss, platelets
arrive and form a fibrin clot, platelets signal growth factors, histamine causes
vasodilation and delivery of leukocytes, increased vascular permeability also
delivers leukocytes
patients taking anticoagulation drugs will have problems with this phase
white blood cells
neutrophils arrive first and kill debris and remove dead tissue-> pus
(purulence) is a lot of dead neutrophils that have phagocytized debris
macrophages arrive later and are key in the transition from inflammatory to
proliferative phase: secrete collagenase which debrides dead tissue, initiate
angiogenesis and granulation (scar tissue) formation
proliferative phase of healing
begins 3 days post injury and continues for at least 3 weeks. goals: fill-in and
close wound
processes involved: angiogenesis, collagen synthesis, and contraction
macrophages and neutrophils continue to work to control infection
