Wound Management Exam 1
How often does the skin regenerate?
Outer layer is replaced every 28 days
Skin Physiology
Vitamin D production
Sensation
Appearance and self-image
Wound healing and epithelial cell regeneration
Protective barrier
Conservation of fluid, protein, & electrolyte loss
Regulation of body temperature
Secretory ability
Two layers of the skin
Epidermis
Dermis
Anatomy of the Epidermis
Avascular layer
Varies in thickness in different body areas
◦Thicker in greater pressure areas
Five layers of the Epidermis
1. Stratum Corneum (waterproof; constantly being shed)
2. Stratum Lucidium (soles of feet and palms)
3. Stratum Granulosum (flattened cells)
4. Stratum Spinosum (active growing layer)
5. Stratum Basale (mitotic growth; makes melanin)
Anatomy of the Dermis
Papillary
2 Glands of the skin
Sebaceous glands
Transdermal medication
,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.
Contusion
A region of injured skin in which blood capillaries have ruptured
Ecchymosis
Bluish discoloration resulting from bleeding in the subcutaneous tissue
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 of 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 (dehiscence), often from
infection
Secondary intention of wound closure
◦Wounds that are left open to heal
Tertiary intention of wound closure
◦Surgical incision left open a few days then closed with sutures
◦Often seen when there is a higher risk for infection
Example of superficial wound
1st degree burn; Loss of the epidermis
Partial-Thickness Wounds
Examples: abrasions; skin tears, 2nd degree burns
How do Partial-Thickness Wounds close?
Closes by re-epithelialization
◦Epithelial cells resurface to protect itself from invasion of microorganisms
Full-Thickness Wounds
Loss of all layers of the epidermis, dermis, and subcutaneous tissue
How does Full-Thickness Wounds close
Closes by contraction and scar tissue formation
◦Scar tissue has less elasticity and tensile strength than original tissue
Phases of healing
Inflammatory Phase
Proliferative Phase
Remodeling Phase
,-Number of days a wound spends in each phase varies based on several factors,
such as age, size of wound, co-morbidities, continued trauma, nutrition, blood flow,
medications, stress, and infection
When is the Inflammatory Phase?
Starts moment of injury and lasts 3 - 10 days
What can cause a wound to get stuck in the Inflammatory Phase?
Chronic inflammation associated with necrotic tissue, hematoma, or infection
Goal and first step of the Inflammatory Phase?
Goal: Hemostasis and produce clean wound
First Step: Coagulation Cascade
Coagulation Cascade
Immediate clotting and vasoconstriction to decrease blood loss
What happens during Coagulation Cascade
Platelets arrive and form a fibrin clot
Platelets signal growth factors
Histamine causes vasodilation and delivery of leukocytes
Increased vascular permeability also delivers leukocytes
What pts. might have problems in the inflammatory phase?
Patients that are taking anticoagulation drugs will have problems with this phase
What arrives first to an injury?
Neutrophils
What is pus?
◦Pus is a lot of dead neutrophils that have phagocytized debris
What arrives to wounds later?
Macrophages arrive later and are key in the transition from inflammatory to
proliferative phase
What do macrophages secrete? What does this initiate?
◦Secrete collagenase which debrides dead tissue
◦Initiate angiogenesis and granulation (scar tissue) formation
When does the proliferative phase occur?
Begins 3 days post injury and continues for at least 3 weeks
Goals of proliferative phase
fill-in and close wound
Processes involved in the Proliferative phase
angiogenesis, collagen synthesis, and contraction
What do macrophases and neurtrophils do during the proliferative phase?
Macrophages and neutrophils continue to work to control infection
Angiogenesis
Granulation buds begin pink then become beefy red with increased blood vessels
, Cross-Linking of Collagen
3 weeks after wounding, tensile strength is only 15%. New scar won't tolerate
mobilization.
Why is cross linking of collagen important to PTs
Very important to know for PTs who want to start scar tissue mobilization along
incision line to get scar tissue to lay down in an orderly-fashion, versus random,
haphazard fashion.
How does contraction help wound healing?
Contraction changes wound shape and decreases open area
Primary intention or partial thickness heal very little by contraction but full-thickness
heal a lot (up to 40%) by contraction
What can excessive contractions lead to?
contractures
◦Don't want contractures around hand, neck or face - surgeons usually graft in these
areas
When does the remodeling phase occur?
Can begin as early as Day 9 and can last up to 2 years
In deep wounds, what happens to skin appendages?
In deep wounds, skin appendages are rarely repaired. Instead scar tissue forms in
its place.
What happens during the remodeling phase?
-Highly vascular tissue is replaced with less vascular tissue (tissue changes from red
to pink to white)
-Tissue is gaining strength
At day 21, tissue only has _______ tensile strength
15%
Goal of remodeling phase
increase tensile strength of scar tissue
◦By end of phase, tensile strength is at it's strongest - 80%
What delicate equilibrium do we have to pay attention to in the remodeling phase?
Delicate equilibrium between wound reopening or hypertrophy/keloid scars
Hypertrophic scar
◦Raised scar that stays within the boundaries of the original wound
How often does the skin regenerate?
Outer layer is replaced every 28 days
Skin Physiology
Vitamin D production
Sensation
Appearance and self-image
Wound healing and epithelial cell regeneration
Protective barrier
Conservation of fluid, protein, & electrolyte loss
Regulation of body temperature
Secretory ability
Two layers of the skin
Epidermis
Dermis
Anatomy of the Epidermis
Avascular layer
Varies in thickness in different body areas
◦Thicker in greater pressure areas
Five layers of the Epidermis
1. Stratum Corneum (waterproof; constantly being shed)
2. Stratum Lucidium (soles of feet and palms)
3. Stratum Granulosum (flattened cells)
4. Stratum Spinosum (active growing layer)
5. Stratum Basale (mitotic growth; makes melanin)
Anatomy of the Dermis
Papillary
2 Glands of the skin
Sebaceous glands
Transdermal medication
,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.
Contusion
A region of injured skin in which blood capillaries have ruptured
Ecchymosis
Bluish discoloration resulting from bleeding in the subcutaneous tissue
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 of 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 (dehiscence), often from
infection
Secondary intention of wound closure
◦Wounds that are left open to heal
Tertiary intention of wound closure
◦Surgical incision left open a few days then closed with sutures
◦Often seen when there is a higher risk for infection
Example of superficial wound
1st degree burn; Loss of the epidermis
Partial-Thickness Wounds
Examples: abrasions; skin tears, 2nd degree burns
How do Partial-Thickness Wounds close?
Closes by re-epithelialization
◦Epithelial cells resurface to protect itself from invasion of microorganisms
Full-Thickness Wounds
Loss of all layers of the epidermis, dermis, and subcutaneous tissue
How does Full-Thickness Wounds close
Closes by contraction and scar tissue formation
◦Scar tissue has less elasticity and tensile strength than original tissue
Phases of healing
Inflammatory Phase
Proliferative Phase
Remodeling Phase
,-Number of days a wound spends in each phase varies based on several factors,
such as age, size of wound, co-morbidities, continued trauma, nutrition, blood flow,
medications, stress, and infection
When is the Inflammatory Phase?
Starts moment of injury and lasts 3 - 10 days
What can cause a wound to get stuck in the Inflammatory Phase?
Chronic inflammation associated with necrotic tissue, hematoma, or infection
Goal and first step of the Inflammatory Phase?
Goal: Hemostasis and produce clean wound
First Step: Coagulation Cascade
Coagulation Cascade
Immediate clotting and vasoconstriction to decrease blood loss
What happens during Coagulation Cascade
Platelets arrive and form a fibrin clot
Platelets signal growth factors
Histamine causes vasodilation and delivery of leukocytes
Increased vascular permeability also delivers leukocytes
What pts. might have problems in the inflammatory phase?
Patients that are taking anticoagulation drugs will have problems with this phase
What arrives first to an injury?
Neutrophils
What is pus?
◦Pus is a lot of dead neutrophils that have phagocytized debris
What arrives to wounds later?
Macrophages arrive later and are key in the transition from inflammatory to
proliferative phase
What do macrophages secrete? What does this initiate?
◦Secrete collagenase which debrides dead tissue
◦Initiate angiogenesis and granulation (scar tissue) formation
When does the proliferative phase occur?
Begins 3 days post injury and continues for at least 3 weeks
Goals of proliferative phase
fill-in and close wound
Processes involved in the Proliferative phase
angiogenesis, collagen synthesis, and contraction
What do macrophases and neurtrophils do during the proliferative phase?
Macrophages and neutrophils continue to work to control infection
Angiogenesis
Granulation buds begin pink then become beefy red with increased blood vessels
, Cross-Linking of Collagen
3 weeks after wounding, tensile strength is only 15%. New scar won't tolerate
mobilization.
Why is cross linking of collagen important to PTs
Very important to know for PTs who want to start scar tissue mobilization along
incision line to get scar tissue to lay down in an orderly-fashion, versus random,
haphazard fashion.
How does contraction help wound healing?
Contraction changes wound shape and decreases open area
Primary intention or partial thickness heal very little by contraction but full-thickness
heal a lot (up to 40%) by contraction
What can excessive contractions lead to?
contractures
◦Don't want contractures around hand, neck or face - surgeons usually graft in these
areas
When does the remodeling phase occur?
Can begin as early as Day 9 and can last up to 2 years
In deep wounds, what happens to skin appendages?
In deep wounds, skin appendages are rarely repaired. Instead scar tissue forms in
its place.
What happens during the remodeling phase?
-Highly vascular tissue is replaced with less vascular tissue (tissue changes from red
to pink to white)
-Tissue is gaining strength
At day 21, tissue only has _______ tensile strength
15%
Goal of remodeling phase
increase tensile strength of scar tissue
◦By end of phase, tensile strength is at it's strongest - 80%
What delicate equilibrium do we have to pay attention to in the remodeling phase?
Delicate equilibrium between wound reopening or hypertrophy/keloid scars
Hypertrophic scar
◦Raised scar that stays within the boundaries of the original wound
