Plastic Surgery Flashcards
Description of burn severity
1) depth
depth usually difficult to determine initially and easier to determine after 24 hours
depth based on layers of skin involved in the burn, from superficial to deep
2) percentage of total body surface area
burns need to be described in terms of % total body surface area (TBSA), which is estimated by rule of 9’s for any patient >9 years
head, chest, abdomen, upper back, lower back, left arm, right arm, anterior left leg, posterior left leg, anterior right leg and posterior right leg each approximately have 9% TBSA
genital area approximately have 1% TBSA
for patchy burns, % TBSA estimated using palm method where palm without fingers = 0.5% TBSA and palm with fingers = 1% TBSA
Lund-Browder chart is more accurate and often used in children <9 years
Superficial burns: Involved tissue Appearance Sensation Healing time Common cause
Involved tissue - epidermis
Appearance - Dry, red, Blanches with pressure
Sensation - Painful
Healing time - 3-6 days
Common cause - UV exposure, very short flash
Superficial partial thickness burns: Involved tissue Appearance Sensation Healing time Common cause
Involved tissue - epidermis and part of dermis
Appearance - Blisters, moist, red, weeping, blanches with pressure
Sensation - Painful to temperature and air
Healing time - 7-20 days
Common cause - Scald (spill or splash), short flash
Deep partial thickness burns: Involved tissue Appearance Sensation Healing time Common cause
Involved tissue - epidermis and part of dermis
Appearance - blisters that are easily unroofed, wet or waxy, dry, variable colour, does not blanch with pressure
Sensation - perceptive of pressure only
Healing time - >21 days, scarring
Common cause - scald (spill), flame, oil, grease
Full thickness burns: Involved tissue Appearance Sensation Healing time Common cause
Involved tissue - epidermis and all of dermis
Appearance - waxy white to leathery gray to charred and black, dry and inelastic, no blanching with pressure
Sensation - deep pressure only
Healing time - never heals if >2% TBSA, which would require skin grafting to replace dermal integrity
Common cause - scald (immersion), flame, steam, oil, grease, chemical, electrical
Fourth degree burns: Involved tissue Appearance Sensation Healing time Common cause
Involved tissue - skin and underlying tissue (fascia/muscle)
Appearance - underlying tissue visible
Sensation - deep pressure only
Healing time - never heals, requiring skin grafting to replace dermal integrity
Common cause - scald (immersion), flame, steam, oil, grease, chemical, electrical
ABA burn severity grading system
American Burn Association grading system classified into minor, moderate or major burn based on depth and % TBSA
minor burn =
<15% TBSA in adults
<10% in children and older adults
<2% TBSA full thickness burn
moderate burn =
15-25% TBSA with <10% full thickness burn
10-20% TBSA partial thickness burn in children under 10 and adults over 40 with <10% full thickness burn
major burn =
25%+ TBSA
20%+ TBSA in children <10 and adults >40 years
10%+ full thickness burn or involving eyes/ear/face / hands / feet / perineum that are likely to result in cosmetic of functional impairment or high voltage electrical burn or major trauma or inhalation injury or poor risk patients with burn injury
Primary management of burns
1) Stabilize
2) Assessment of Burn - depth and % TBSA
3) Airway Management if Inhalation Injury
airway management mainly address A) inhalation injury and B) CO poisoning
A) inhalation injury
inhalation injury cause progressive upper airway edema, eventually closing up airway, which is leading cause of death in burn patients
inhalation injury also cause pulmonary injury, causing pulmonary edema and insufficiency by 2-3 days
B) CO poisoning
bronchodilator (Albuterol) if bronchospasm
steroids not indicated in burn patients
4) Fluid Resuscitation
2 large IV bores for IV crystalloids
fluid resuscitation need to be accurate, because inadequate fluid resuscitation increases risk of mortality while over-resuscitation can cause pulmonary edema / acute respiratory distress, pneumonia, multi-organ failure, compartment syndromes
estimation of initial fluid requirement based on Parkland formula
extra fluid administration for the following cases: burn >80% TBSA, 4th degree burns, associated traumatic injury, electrical burn, inhalation injury, delayed resuscitation, pediatric burn
target hourly urine output should be maintained at 0.5mL/kg per hour for adults and 1mL/kg per hour for children
blood transfusion should be avoided when possible
indication for blood transfusion = hemoglobin <80g/L in patient without acute coronary syndrome (ACS) or <100g/L in patient with ACS
5) Immediate Burn Care & Cooling
any hot or burned clothing, jewelry and debris should be immediately removed
burned area should be cooled immediately using cool water or saline soaked gauze (12C) for 15-30 minutes
monitor core body temperature continuously, because cooling of burns >10% TBSA can cause hypothermia which can be treated with warmed IV fluids to maintain temperature >35C
6) Pain Management
IV morphine for pain
Clinical presentation, physical exam, investigations, diagnosis and management for significant smoke inhalation injury
1) history
burn in a closed space
2) symptoms
hoarseness, persistent cough, stridor or wheezing
3) inspection
conjunctivitis
nares with inflammation or singed hair
carbonaceous sputum or burnt matter in mouth or nose
blistering or edema of oropharynx
deep facial or circumferential neck burns
4) general physical exam
depressed mental status including evidence of drug or alcohol use
respiratory distress, tachypnea
5) investigations
hypoxia or hypercapnia
elevated carbon monoxide (CO) or cyanide level
investigations for inhalation injury and respiratory distress include
vitals: oxygen saturation
arterial blood gas, serial peak expiratory flow rates (PEFR) if obtainable
chest X-ray
capnography, which can monitor end-tidal CO2 (EtCO2)
blood labs: serum lactate; serum cyanide level, blood carboxyhemoglobin (HbCO) level for moderate or severe burns
ECG to assess cardiac function
6) Diagnosis
inhalation injury can be diagnosed on direct bronchoscopy, and cannot be diagnosed based on chest X-ray or arterial blood gas
7) Management
patients with signs of smoke inhalation injury should be given supplemental oxygen and intubated early and prophylactically even without respiratory distress
Signs of CO poisoning
signs of CO poisoning: headache, confusion, coma, arrhythmias
Diagnosis of CO poisoning
CO poisoning diagnosed based on high HbCO
Management of CO poisoning
reversed with hyperbaric oxygen treatment
Cyanide poisoning diagnosis
cyanide poisoning diagnosed based on high blood cyanide level or high serum lactate plus low / decreasing EtCO2
Cyanide poisoning treatment
reversed with hydroxocobalamin
Parkland formula
Calculation for fluid resuscitation for burns
4mL/kg for each % TBSA burned over course of 24 hours where 1/2 is delivered in first 8 hours and other
1/2 is delivered in the subsequent 16 hours
e.g. 70kg patient with 10% TBSA burn = 4mL/kg x 70kg x 10 (for % TBSA) = 2800mL over 24 hours, so 1400mL over first 8 hours (i.e. 175mL/hr for first 8 hours) and 1400mL over subsequent 16 hours (i.e. 87.5mL/hr for subsequent 16 hours)
Hour 24-30 – 0.35-0.5 cc plasma/kg/%TBSA
Hour >30 – D5W at rate to maintain normal serum sodium
Secondary burn management
1) Further Investigations
2) Prevention of Infection
tetanus prophylaxis with 0.5cc tetanus toxoid for any burn deeper than superficial or >10% TBSA
tetanus immunoglobin if prior immunization is absent, unclear or out dated >10 years ago
topical antibiotics (Silver Sulfadiazine SSD) applied to all non-superficial burns
Bacitracin for skin near eyes & mouth, sulphonamide hypersensitivity, pregnant mothers, newborns and nursing mothers
3) Wound Management (Minor to Severe Burns)
if not already done, remove clothing / jewelry / debris and cool wound with saline-soaked gauze (12C)
a) pain management
minor burn can be treated with acetaminophen and NSAID in combination with opioids if required
superficial burn can be treated with non-perfumed moisturizing cream (Vaseline, Nivea) applied to wound with aloe for pain control and keeping skin moist
b) burn wounds cleaned and irrigated
embedded foreign body removed by irrigation
wound washed with mild soap and tap water
c) debridement
sloughed or necrotic skin including ruptured blisters are debrided
d) wound dressing
all partial and full thickness burns should have dressings
e) escharotomy
f) skin grafting
g) rehabilitation
prevention of wound contracture with pressure dressing, joint splints and early physiotherapy
4) NG Tube
thermal burn shock may cause mesenteric vasoconstriction causing gastric distension, ulceration and aspiration
for patients with moderate or severe burns >20% TBSA, nasogastric (NG) tube
What is an eschar, eschartotomy and indications for escharotomy
eschar = stiff and unyielding dermis with deep dermal and full thickness burns
escharotomy = incision of eschar with coagulation electrocautery or scalpel
eschar may limit respiratory function (such as eschar in neck and chest), which require emergency escharotomy
circumferential eschar may cause compartment syndrome or distal ischemia, thus require decompressive escharotomy
Indication for skin grafting in burn
indication for skin graft = full thickness and 4th degree burns that is bigger than size of quarter
Wound dressing for burn process
before wound dressing, the burn should be cleaned thoroughly, debrided and topical antibiotics should be applied
topical antibiotics to prevent infection and sepsis by common skin organisms (Gram positive day 1-3 including staphylococcus aureus; gram negative day 3-5 including
pseudomonas, proteus, klebsiella; Candida)
basic dressing = 1st layer of fine non-adherent mesh gauze (Telfa, Adaptic) placed over burn, 2nd layer of fluffed dry gauze and 3rd layer of elastic gauze roll (Kerlix)
dressing in successive strips held in place using tubular net bandage or gauze wraps
individually wrap and separate with fluffed gauze all toes and fingers to prevent adherence and maceration
dressing change can range from twice daily to weekly
once epithelialization occurs, non-perfumed moisturizing cream (Vaseline, Nivea) applied to wound
Complications of burn
hypermetabolism: nutrition should meet increased metabolic rate with adequate calories, vitamin C, vitamin A, Ca, Zn, Fe
immune suppression: increased risk of sepsis so must monitor for signs of sepsis and treat aggressively with antibiotic therapy if present
GI bleed: NG tube feeding or NPO with TPN; may add antacid and anti-histamine blocker to prevent GI bleed
renal failure: renal failure usually due to pre-renal or myobloginuria, which can be prevented with adequate fluid resuscitation
pulmonary insufficiency (due to inhalation injury, pneumonia, cardiac decompensation, sepsis): treated with intubation and mechanical ventilation
wound contracture and hypertrophic scaring: prevented with timely wound closure, splinting, pressure garments and physiotherapy
vascular permeability and edema
altered hemodynamics (decreased CO, increased SVR)
Burn indication for admission to hospital
moderate to major burns according to ABA grading system
involvement of face, neck, hands, feet, genitalia, perineum, major joints
suspected inhalation injury
circumferential partial or full thickness burn
immune compromised patients or poor expected recovery (diabetics, elderly)
chemical burn
high voltage injury with abnormal ECG
Transfer to burn centre indications
major burn based on ABA grading system should be transferred to a burn center
> 10% TBSA partial thickness burn
> 5% TBSA full thickness burn
burn involving face, neck, hands, feet, genitalia, perineum or major joints
pre-existing medical condition that can complicate management, prolong recovery or adversely affect outcome
special requirement (social, emotional or long term rehabilitative needs)
children who require qualified pediatric personnel and equipment
Stages of wound healing
“In Every Fresh Cut” = Inflammation, Epithelization, Fibroplasia, Contraction
1) Inflammatory Reactive Phase (day 1-6)
inflammation limits damage and prevent further injury
debris and organisms cleared by inflammatory response, mainly neutrophils in day 1-2 and macrophages in day 2-4
hemostasis achieved by vasoconstriction and platelet plug
2) Proliferative Regenerative Phase (day 4 to week 3)
macrophage secrete growth factors that recruit and activate fibroblasts
fibroblasts initiate reparative process of re-epithelialisation, matrix synthesis (mainly type 3 collagen synthesis) and angiogenesis
reparative process increase tensile strength of wound by day 4-5
3) Remodelling Maturation Phase (week 3 to 1 year)
increasing collagen organization and stronger cross links, resulting in wound contraction, scarring, then remodelling of scarring
type 1 collagen replaces type 3 until 4 to 1 ratio is achieved
peak tensile strength at 60 days, which is 80% of pre-injury strength
Primary closure indication, contraindication and mechanism
indication: recent (<6 hours) and clean cut wounds such as surgical wounds or acute traumatic wounds where wound edges can be brought together by external mechanism
contraindication: bite wounds, crush injury, infection, long time lapse since injury (>6 hours), retained foreign body
mechanism: wound edges brought together by stitches, staples or adhesive tape within hours of wound creation
Secondary closure indication, mechanism
indication: wound that cannot be cleaned or wound too large that skin cannot be brought together (e.g. ulcer)
mechanism: wound healed spontaneously by body without any external mechanism means
spontaneous healing at rate of 0.75 mm/day from wound margins in concentric pattern
require wound care and have inferior cosmetic result
Tertiary closure (aka delayed primary closure) indication, mechanism
indication: chronic or contaminated wounds where wound edges can be brought together by external mechanism; severe crush injury with significant tissue devitalization
mechanism: wound left open (often healing interrupted with packing), cleaned and observed, where it may be closed 4-5 days later (when granulation / epithelization occurred)
prolonged inflammatory phase to decrease bacterial count and lessen chance of infection after closure
require wound care
Wound contamination definition
contamination = presence of non-replicating micro-organism within wound
Wound colonization definition
presence of replicating microorganism within wound
Wound infection definition
> 105 micro-organism (or small amount of virulent organism) in wound without intact epithelium
Acute management of contaminated wounds <24h
evaluate for injury to underlying structure (blood vessel, nerve, tendon, bone)
control active bleeding
cleanse and irrigate open wound with physiologic solution (NS or RL)
surgical debridement with blade and irrigation to remove foreign material, devitalized tissue, old blood
Systemic antibiotics and tetanus toxoid, immunoglobin and immunization where applicable
post exposure treatment of hepatitis B / C or HIV if indicated
re-evaluate wound at 24-48 hours for signs of deep infection (erythema, swelling, warmth, pain, purulence), where infected wound need to have sutures removed and opened
Indication for systemic antibiotics in contaminated wounds
Clinically infected wound (wound redness, swelling, pain, purulence; fever; leukocytosis)
wound >8 hours
severely contaminated wound
immune compromised patient
wound involving deeper structure
Tetanus prone wound characteristics
> 6h since injury
> 1cm depth of injury
Crush, burn, gunshot, frostbite, puncture thorugh clothing, farming injury mechanism of injury
Devitalized tissue present
Contamination present
Retained foreign body present
Tetanus immunization recommendations
1) Uncertain or <3 doses of immunization :
A) Clean, minor wound
Tdap yes, Tig No
B) All other wounds
Tdap yes, Tig yes
3 doses received in immunization series
A) Clean, minor wounds
Tdap no, but yes if >10 years since last booster
Tig No
B) All other wounds
Tdap No, but yes if >5 years since last booster
Tig no, but yes if immunocompromised
Long term management of contaminated wounds >24h
irrigation and debridement
topical antimicrobial
systemic antibiotics if clinical signs of infection (wound redness, swelling, pain, purulence; fever; leukocytosis)
when bacterial count <10^5, closure usually by secondary intention, but may be by tertiary intention, skin graft or flap
Indications for wound care
wound care only in 2nd or 3rd intention wound healing
in general, wound care indicated for any chronic non-healing wounds including surgical wounds and traumatic wounds
diabetic wounds/ diabetic foot ulcer
venous leg ulcers
pressure ulcer
complex soft tissue wounds
infected wounds
What is wound care
wound care encompasses all management to facilitate healing of wound, which can be any combination of the following
medical care: antibiotics, controlling of blood sugar
wound debridement: irrigation, surgical
topical therapy: antiseptics, antimicrobial agents
wound dressings
wound packing
wound closure
Aspects of wound care
A) Medical management
systemic antibiotic therapy for clinically infected wound with any of the following
local signs: cellulitis, lymphagitic streaking, purulence, malodor, wet gangrene, osteomyelitis
systemic signs: fever, chills, leukocytosis, nausea, hypotension, hyperglycemia, confusion, blood glucose control, especially for diabetic patients
B) Debridement
C) Topical Therapy
antimicrobial cadexomer iodine (Iodosorb)
D) Wound Dressing
wound dressing should eliminate dead space, control exudate, prevent bacterial overgrowth, ensure proper fluid balance
primary goal of dressing = maintain moisture in wound environment
E) Wound Packing
wound packing usually indicated for large soft tissue defects (area of dead space between surface of intact healthy skin and wound base)
wound packing with gauze dressing requires frequent dressing changes usually 2-3 times daily such that the gauze does not completely dry out
wound dressing stopped when necrotic tissue have been removed and granulation is occurring
F) Wound Closure / Coverage
wound closure in wound care as tertiary intention (delayed primary closure)
chronic wound should never be closed primarily, and only delayed primary closure in some cases
wounds are closed by delayed primary closure if it demonstrates progressive healing based on granulation tissue and epithelization
negative pressure wound therapy for deep wounds to reduce complexity and depth of defect prior to definitive closure
after sufficient wound care wound can be closed by
closure with suture, staple or tape coverage with skin grafts
Classification of skin graft
1) Species classification
autograft = donor and recipient sites on same individual
allograft (homograft) = donor site from one human to an recipient site on another human
xenograft (heterograft) = donor site from a different species (e.g. pig) to an recipient site on a human
2) Thickness classification
split vs full thickness (some vs all of dermis)
Split thickness vs full thickness skin graft
split thickness skin graft can be used as mesh graft, which can cover a large area
advantage: best for contaminated recipient site, prevent accumulation of fluids (hematoma, serum)
disadvantage: poor cosmoses (alligator hide appearance), significant secondary contracture
Full thickness
advantages: may use on face and fingers
disadvantages: lower rate of survival (thicker, slower vascularization)
Unsuitable and suitable vascularized beds for skin graft
unsuitable bed due to lack of vascularization: bone, tendon, cartilage
suitable vascularized bed: muscle, fat, periosteum
Skin graft will take under the following conditions
vascularized bed
non-contaminated wound with bacteria count <10^5
minimize shearing motion and fluid (including seroma and hematoma) beneath graft, where immobilization by staples, sutures, splinting and appropriate pressure dressing are used to prevent graft movement, hematoma and seroma formation
Causes for skin graft loss
fluid collection: hematoma, seroma
infection
mechanical force: shearing, pressure
Skin flaps definition
tissue transferred from one site to another with its original blood supply, thus not dependent on neovascularization on recipient site
skin flaps may consist of skin, subcutaneous tissue, fascia, muscle, bone and other tissue
Indication for skin flaps
reconstruction to replace tissue loss due to trauma or surgery
provide temporary skin and soft tissue cover through which surgery can be carried out later
improves blood supply to poorly vascularized bed such as bone
Classification for skin flaps
skin flaps can be classified based on blood supply or anatomic location
1) blood supply: random, axial
a) random pattern flaps
random pattern flaps have random vascular supply
limited length to width (2 to 1) ratio to ensure adequate blood supply
b) axial pattern flaps
flap contains a well defined artery and vein
allows greater length to width (6 to 1) ratio
2) anatomic location: local, regional, distant
What can cause skin flap loss
fluid collection: hematoma, seroma
infection
poor flap design
mechanical forces: compression
vascular failure or thrombosis
fat necrosis
Characteristics of basal cell carincoma
nodulo-ulcerative type: papule / plaque / nodule with white translucent shiny scaly (“pearly”) borders usually well defined, which may contain telangiectasia (tiny blood vessel)
lesion may have erosion or ulceration
variant include
pigmented variant: flecks of pigment in translucent lesion, which may mimic melanoma
superficial variant: flat tan to red brown plaque, with scales, pearly border and fine telangiectasia
sclerosing variant: flesh / yellowish coloured shiny papule / plaque with indistinct border
Typical location of basal cell carcinoma
Sun exposed area such as face, neck and back of hands
Etiology of basal cell carcinoma
cancer arising from basal stem cells of epidermis
