5. Burns and Wounds Flashcards
What are burns?
traumatic injuries to the skin or other tissues by thermal cause or other exposures
T/F: burns are an isolated, nonrecurring insult
true
What causes a burn?
heat
electrical discharge
friction
chemicals
radiation
A heat injury can be related to:
contact temperature
duration of contact
thickness of skin
A heat injury involves what area(s) of the skin
epidermis and part of the dermis
Most heat injuries are caused by?
flames
hot liquids
hot solid objects
steam
electrical discharge is
electric energy transferred into heat
How does electricity pass through the body
it passes through poorly conducting body tissues
what disrupts membrane potential and function (injury to the cell membrane) in electrical discharge injuries?
electroporation
What dictates the severity of an electrical discharge injury
pathway of current
resistance to the current flow through tissues
strength and duration of current flow
what leads to a friction injury
mechanical disruption of tissues
heat generated by friction
the severity of chemical injury is determined by
duration of exposure
nature of agent
what are acid burns?
coagulation necrosis of tissue
what are alkaline burns?
liquification necrosis
What can ionizing radiation trigger?
merkel cell carcinoma
Merkel cell carcinoma is another name for what?
sunburn
therapeutic radiation is dependent on what factors?
dose
time of exposure
type of particles
what type of burns can radiation cause?
deep internal burns
first degree burn
superficial; epidermal burn that only involves the epidermal layer of skin
second degree burn
partial thickness - involves the epidermis and portions of the dermis
how are second degree burns characterized?
superficial or deep
third degree burns
full thickness - extends through and destroy all layers of the dermis and often injure the underlying subcutaneous tissue.
fourth degree
deep burn injury - extends into underlying soft tissue and can involve muscle and or bone
the classification by depth(new) did what?
extends into subcutaneous soft tissue
involves vessels, nerves, muscles, bones, and joints
what is the healing time for superficial /first degree burns
3-6 days
what is the healing time for superficial partial thickness /second degree burns
7-21 days
what is the healing time for deep partial thickness /third degree burns
> 21 days; surgical treatment
what is the healing time for full thickness /fourth degree burns
rare unless surgically treated
what is the healing time for deeper injury /fourth degree burns
never; unless surgically treated
what is the appearance of deep partial thick depth burns?
blisters; blanching with pressure may be sluggish
what is the assessment of burns
can progress and convert into deeper wounds over several days
thin skin sustains deeper burn injuries that may be initially apparent
what are some areas that may sustain deeper burn injuries
volar surfaces of the forearms
medial thighs
perineum
ears
how are burns assessed?
at percentage of total body surface area affected
are superficial burns are not accounted for in percentage?
no
oral burns
hot liquids or foods
inhalation of hot vapors or liquids
holding flammable /corrosive objects in the mouth
minor burns on the lips
oral commissure
oral mucosa
what are examples of oral burns from hot liquids or solids
tea, cheese, potatoes, noodles, spicy foods, coffee
what is treatment for minor burns on lips
vasline
topical antibiotic ointment
what should be avoided for burns to the oral mucosa
pH changes in the mouth
what development should we look for in burns to the oral mucosa?
microstomia
what are the basic steps of burn management
removal of clothing, debris
cooling
cleansing
dressing
pain management
tetanus prophylaxis
close follow up
what is the difference between acute vs chronic wounds: time
acute = short
chronic = not healed @ 6 weeks
what is the difference between acute vs chronic wounds: neutrophil, elastase, MMP levels
acute = low
chronic = high (bacterial infection)
classification of wounds
open vs closed
what are the characteristics of open vs closed
penetrating vs non penetrating
mechanism
what is the appearance of an open wound
deep layers and tissues are exposed
what is the appearance of a closed wound
superficial layer of the body remains intact
what are the types of wounds based on
mode of entry
abrasion
grazing injury
scrapping off the superficial layer
incision
caused by a sharp-edged structure
margin is straight
laceration
caused by blunt object
margin is irregular
stab/puncture/penetration
caused by sharp, pointed object-directed perpendicular to skin
margin of the wound has split ends (fish tail)
amputation
caused by force opposite direction
how many stages of open wounds are there
4
stage 1 open wound
burn
superficial
skin is intact
stage 2 open wound
open wound
superficial laceration/puncture
epidermis with dermis
stage 3 open wound
open wound/deep
full thickness
all layers involved (inc. subcutaneous layer)
stage 4 open wound
open wound; deep lacerations
burn; full thickness
all layers down to muscle, bone, and tendon
Phases of normal wound healing
coagulation
inflammatory
proliferative/granulation tissue formation
remodeling
remodeling phase
fibroblast proliferation
matrix formation
apoptosis of fibrobastic cells
formation for acellular scar tissue
what is needed for fibroblast proliferation
VEGF
What is produces in matrix formation during the remodeling phase
collagen III, fibrin, fibronectin, hyaluronic acid
when does the proliferative phase occur
2-3 days after injury
what induces and maintains cellular proliferation
inflammatory cells (leukocytes, neutrophils, macrophages)
what is produced in the proliferative phase needed for the remodeling phase
VEGF, FGF-2, PDGF
what does PDGF trigger
formation of granulation tissue
intial epethialization
angiogenic induction - endo progenitor cells
when does the inflammatory phase occur
hours after injury
PGDF, TGF A1, TGF A2 attract leukocytes, neutrophils, and macrophages
