Burns


DEFINITION
Trauma from fire, heat, electricity, chemicals, scalding water, causing from minor to very serious tissue damage.
Immediate treatment
See also Cold Injuries
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INCIDENCE
Incidence
1% of pop burned/ scalded annually.
<50% severe enough to stop activity/ seek medical attention.
Fatality rate 1-4 in 100,000.
"It is the impoverished, addicted, disturbed or foolish who so often become another burn statistic" (ACLS book)

Geography
More common in colder climes.
More severe in some cultures (clothing related).
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AETIOLOGY
Trauma
Fire, heat, electricity, chemicals, scalding water
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BIOLOGICAL BEHAVIOUR
Classification

Depth

Superficial partial (epidermal)
(1st degree)
- heal from bottom up.
- deep hair / gland epithelial cells survive
- minimal scarring.

Deep partial, deep dermal

(2nd degree)
- eg from boiling water.
- also heal from deeper appendages.
- take 3-4wks
- leave scarring.

Full thickness (subcut)

(3rd degree)
- eg fire, hot metal, acids, alkalis, electrical.
- heel from edges, heavy scarring
- require skin grafting.

Deep burns

(prev 4th degree)
- to muscle / bone.

Systemic Consequences

Burns >20% are life-threatening.
Massive shift of fluid to extracellular space; hypovolemic shock - induced inflammatory response and catabolic state

Fluid

Consider Starling's forces
- net filtration increases, interstitial compliance increases and oedema
- lymphatic system overwhelmed (and often damaged);
- ongoing cytokine action on permeability from proteases following apoptosis of damaged areas.
--> widespread homeostatic disruption.

Metabolics

1. Hormone surges; insulin, IGF-1, GH
Changes protein balance; loss of lean mass.
- young children especially vulnerable.
Insulin resistance also occurs; cell-receptors function inadequately; may last months with hyperglycemia.
Lack of androgen production; testosterone may help but have undesired side effects; thus oxandrolone synthetic androgen used.

2. Metabolic acidosis.
Local release of lactate, serum lactate can guide oxygen demand goals, 1 ampule sodium bicarb to resuscitation fluids can help

3. Protein metabolism
- glucocorticoids increase,, insulin decrease
- catabolic state


Complications

Airway

Burns to upper airway from smoke / steam inhalation.
More in confined spaces.

Breathing

Inhalation may also injure lower airway and lung
- even in absence of skin involvement.
Also beware noxious fumes.

Circulation

Capillaries increase in permeability.
--> free egress of fluid, electrolytes & proteins.
- if >30% SA, egress is generalized, including pulmonary capillaries.
- max first 12-18hr, still high at 36hr.
- thereafter slow reabsorption.

Circumferential burns
May obstruct blood flow beneath.
--> compartment syndrome, chest compression.

Infection
Historically a massive problem.
Wide variety of bugs have easy access to blood and sepsis results.
Systemic fungal infections among most serious.

Nutrition
Highly catabolic.
Loss of protein thought burn, healing requirements, fever, infections, anorexia +/- paralytic ileus.
Fat and muscle stores drop.




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MANIFESTATIONS

Symptoms
Local
Pain may be severe if superficial.
Local symptoms by site.

Remember to ask:

Clothing worn
Cooling already applied
Time of burn
- explosions may result in internal injuries or #s.
Temperature
AMPLE

Systemic

Fluid loss.
Catabolism
- Nausea & ileus can persist for days.
Depression.

Complications

As above.

Signs

Airway
Oedamatous lips, tongue, pharynx
Face and/or neck burns
Singeing of eyebrows and nasal vibrissae
Carbon deposits / inflammation in oropharynx
Carbonaceous sputum
Hoarseness
Impaired mentation or confirement in a burning environment
Stridor.
Breathing
Circulation

Assess area

- do not include areas of erythema or 1st degree burns
Rule of 9s
Head, arms = 9 each
Front, back, legs = 18 each
Groin = 1.
Palms
For scattered burns
patient's palm = 1% of body.
Children
Proportionately larger heads.
image

Assess depth
Superficial
Erythema, pain, no blisters
Partial
Red, mottled, oedematous, blister.
May have a weeping wet appearance.
Painfully hypersensitive.
Deeper partial
Swell, blister
Not so sensitive to touch, but still to pinprick.
Full thickness
Dry, leathery or charred, or denuded.
May be translucent, mottled or waxy white.
- surface may be red but non-blanching.
Insensitive to pain.

Note site
?nerves close eg behind elbow, head of fibula.
?Circumferential burns

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INVESTIGATIONS

Bloods

FBC
Us+Es
- get early & burns unit will want to know.
G+H/X-match
Pregnancy test for all females
ABG

Smoke inhalation

Blood gases.
Carboxyhaemoglobin.

Imaging
CXR
Others as indicated.

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MANAGEMENT
Stop, drop and roll.
First Aid
Transfer Criteria
Inhalational Burns
Electrical Burns
Chemical Burns

First Aid

Ensure safety.
Remove victim / remove heat.
- remove burning clothing / chemicals (and rinse pt) after airway secure.

ABCs

Airway

- the subglottic airway is relatively protected by larynx.
- the supraglottic airway is extremely susceptible to obstruction
Clear airway.
Suspect C-spine injury.
Suspect inhalational burn if:
- face and/or neck burns
- singeing of eyebrows and nasal vibrissae
- carbon deposits / inflammation in oropharynx
- carbonaceous sputum
- hoarseness
- impaired mentation or confirement in a burning environment
- explosion with burns to head and torso
- carboxyhaemoglobin >10%
Remember
Frequently inhalational burn signs take hours or longer to appear.
Treat inhalational burn with:
- early transfer to a burns unit
- if stridor, oedema intubate immediately (airway oedema may later preclude intubation meaning surgical airway reqd).
- if circumferential neck burns, intubate immediately

Breathing

Compromised by: thermal injury, inhalation, CO poisoning.
100% humidified O2 via mask for all major burns.
Check rate, and inspiration depth.
- suspect problem if RR>20.
- full thickness thoracic burns may need escharotomy.
ABG and baseline carboxyhaemoglobin.
Carboxyhaemoglobin
- often CO is produced in fires.
- displaces O2 and shifts dissociation curve to left.
- diagnose primarily from history.
 - <20% --> usually symptom free
- 20-30% --> headache, nausea
- 30-40% --> confusion
- 40-60% --> coma
- >60% --> death.
- may be pink but apnoeic and hypoxic.
Treating CO inhalation:
100% O2
- CO dissociation t1/2 is 4h at room air, 40mins at 100% O2.

Circulation
Examine vitals, cap refill.
- as per shock evaluation
In children >10% or adults >15-20%, need formal fluid resuscitation (below)
Insert catheter
- aim for >0.5ml/kg/hr adults
- 1ml/kg/hr in kids<30kg (minimum 20ml)

Fluid Resuscitation
Insert large bore cannulae,
- do not be deterred from veins under burnt skin if few options.
Parkland Formula for formal resusciation:
- 2-4 ml Hartmann's per kg per 1% BSA burn in first 24hrs.
- half in 8 hours from burn, rest over next 16 hours.
- start with 4ml/kg/% in deep burns
- reassess frequently
For children, as above and add maintenance of:
- 4% glucose 1/5th normal saline
- 0-10kg: 4 mL/kg
- 10-20 kg: 40 mL/h + 2 ml/kg/h
- >20kg: 60 mL/h + 1mL/kg/h
Beware Na+ depletion from burn, esp in kids
- monitor electrolytes q4-6hrly for large burns
- also monitor ECG
Titrate to urine output of 30-50 ml/hr of 0.5 ml/kg/h
- beware glycosuria in diabetics
- invasive ICU fluid monitoring in severe cases.

Hypertonic saline?
Historic. Increased mortality; do not use

Colloid / Albumin?
Unhelpful until membrane semipermability begins to recover; ie at least >12h after burns
Albumin is small compared to pore siz, no advantages in outcome.

Ongoing fluid management
Maintenance fluids at 1.5 mL/%/kg/h after 24h
Toegether with enteral feeding (below)

Vasopressors
First choices are norepinephrine and dopamine titrated to MAP of 65 or higher.
Surgeons will prefer to avoid catecholamines due to reduce blood supply to major would beds.

Problems
Consider over-resuscitation, under-resuscitation and ABCs
Abdo compartment syndrome; ocular pressure

Cooling
As quickly as possible
- consider if <3hrs.
- if >3hrs just irrigate/wash the area.
Do NOT apply cold water to a pt with extensive burns.
Ideally 8-25oC, continuously running.
- wet towels need rapid changing.
- do not use ice - vasoconstricts.
No longer than 20m
- risk of hypothermia.
- esp because skin regulates temp, undressed and evaporating fluid.
- more so for children, elderly.
After cooling wrap in clean dry towels
- or better cling film (not circumferential)
- keep victim warm, ideally ambient 30oC.

Disability
As per secondary survey

Exposure
Remove clothing & jewellery.

Secondary survey
1. Assess depth/ severity
2. Assess for associated injury as per secondary survey
3. Weigh the pt.
4. Assess distal circulation, use Doppler if required.
--> escharotomy (below) if reqd

Analgesia / Sedatives
- if anxious / restless attend to possible ABC cause first.
- analgesics, narcotics, sedatives in small, frequent doses by IV route only.
- avoid IM/SC as unpredictable uptake.

NG tube

- if serious burn >20%
- or if nausea, vomiting, abdo distension.
- essential prior to transfer.

Dressings

Principles

Meticulous assessment, cleaning.
Dictated by burn.
- partial thickness burns are painful to air currents.
If transfer <3hrs, dry towels or most dressings
- cling film limits evaporation, painless, transparent
- do not wrap it circumferentially.
- moist dressings good for small burns
- dry towels for large burns - prevents excessive heat dissipation in
- avoid SSD as can alter appearance for burns team.
If transfer >3hrs:
- simple paranet and gauze dressings.
Ensure burnt hands spinted in neutral position.

Infection control
Give tetanus / determine +ve status.
SSD shown useful, but has disadvantages.
Some places use large dose broad spectrums, but probably not judicious.
- reserve antibiotics for treatment of infection.

Escharotomy
Rarely required in first 6 hours
Consult a surgeon first.
Indicated in limb / circulatory embarassment.
- limb ischaemia is often insidious.
Only reqd on chest if full thickness, circumferential.
- children have increased risk.
Cut eschar and no more - into subcut fat and as far as unburned skin.
- get advice from burns unit first.
- be aware of anatomy underneath.
Faschiotomy is seldom required unless associated skeletal, crush, high voltage injury.

Admit
If 2nd or worse degree
- over 10% or more if <10 or >50 yrs
- else if over 20% BSA.
- 5% BSA if 3rd degree, any age.
If face, hands or feet, perineum or genitalia, major joints affected.
If electrical, inhalation, chemical, circumferential.
If significant concomitant disease, social special cases e.g. suspicion of abuse.

Nutrition
Ensure adequate protein and calories.
Remember large burns also induce a severe systemic inflammatory response.
Caloric requirement:
e.g. Curreri equation (in kilocalories)
- 16-60y: (25xW) + (40x%TSBA)
- 60y: (25xW) + (60x%TBSA)
70:30 carb fat composition
Separate protein calculation
- need 100 nonprotein calories : 1g protein or less depending on burn severeity,
- trace element supplementation is important.
- jejunal feeding reasonable; TPN considered if all efforts at enteral nutrition fail.



Transfer Criteria
In a peripheral hospital, may undertake 24hrs of early management, else refer early / directly.

Transfer if:
- Burns > 10%SA if <10 or >50 yrs old.
- Burns >20%Sa in other age groups.
- Face, hands, feet, genitals, perineum, major jts.
- Full thickness >5%, any age.
- Electrical
- Chemical
- Inhalational
- Circumferential chest / limbs
- Extremes of age
- Comorbid pts
- Associated trauma but burn major injury
- Facility not qualified / capable
- Non accidental injury or if other need for social / emotional / long-term rehab.

Transport
Coordinate with burns centre.
Ensure ABCs controlled.
Wash wounds (saline / chlorhex1%) & cover.
Analgesia sufficient.

Inhalational Burns
~50% pts with facial burns have inhalational damage.
May need to increase Parklands formula to 6.
- ventilatory support requires more replacement for insensible losses.
Classified as supra vs subglottic.

Supraglottic

Hot gases, enclosed spaces.
Oedema / desquamation of mucosa follows.
Airway obstruction results.
- worse in children.

Subglottic
Combustion products
- not usually thermal injury.
- usually chemicals, carbon, sulphur oxides, nitrogen, phosphorus.
- dissolution in resp mucosa creates corrosive chemicals.

Management
Do not miss inhalational burns
Signs above.
See airway above.
100% humidified O2.
Intubate any victim displaying signs of obstruction.
- stridor and any resp distress are absolute indications.
- if in doubt, do not wait.
- delay / oedema makes intubation very difficult.

Electrical Burns
Frequently more serious than surface suggests.
- body serves as a volume conductor, with major thermal injury to deep tissue around bone.
- I = V/R (Ohm's Law); skin has high resistance to conduction; unless very high voltage e.g. lightning pattern of injury differs.
Contact (direct), arcing and flash (indirect) cause different injury patterns; skin burn vs internal current conduction
Rhabdomyolysis causes myoglobin release.
Deep necrosis is a maor sepsis risk
1. Attend to ABCs.
- massive coagulation necrosis through body can follow
2. Monitor ECG
- cardiac arrhythmias common in direct injuries
3. Institute therapy for myoglobinuria if reqd.
- aim for 100ml/hr urine output in an adult
- if pigment not clearing with increased fluid, give 25g mannitol immediately and add 12.5g mannitol to subsequent litres of fluid.
- correct metabolic acidosis through adequate perfusion, add sodium bicarb to alkalise urine as necessary.

Lightning Burns (and HV electrical burns)
High voltage injuries induce an electoporation phenomenon - lysing cell memgranes and ions can leave cells.
- progressive energy depletion is a hallmark of these injuries.
Lightning is an arc burn exceeding 2M V
- can contact an object being touched, direct strike, side flash thermal burn, shockwave / thermoacoustic (thunderbolt) injury, fall injury after strike.
- direct strikes have major lethal action
- stride potential = conducts along something to hit
- thermoacoustic injuries include tympanic damage, concussive blast-injury
Management
1. ABCs, basic resusctivation.
- early aggressive CPR may be lifesaving.
- prompt transfer while progressive damage unfolds.
2. ATLS burn management; often full thickness
- Parklands
- ECG monitoring
3. Address expected multi-organ internal injury from current conduction.
- muscle injury is devastating; myocyte swelling
- microvascular impairment, commonly compartment syndrome
- bone injury - can be #s.
- kiney injury often profound; ICU management with dialysis; sodium bicarb may help
- neurological / CNS injury
4. Debride necrotic skin early and cover with sterile dressings
5. Optimize nutrition, dressings and plastic consult as required.


Chemical Burns
Continue to burn until neutralised / diluted with water.
- some agents also have systemic toxicity, hydrofluoric acid causes cardiac arrest from hypocalcaemia.
- alkalis worse than acids & burn deeper.
Remove excess dry chemicals with a cloth.
Remove clothing/jewellery.
Then irrigate with running water for >1/2hr.
- >1hr for alkalis.
Neutralising agents have no advantage over water.
UNLESS a sodium/potassium/lithium burn, which ignite with H20.
- cover with mineral oil or excise.
Consult ophthalmologist for eye involvement.

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Jerome's Notes


Burns

temperatures >40°C cause skin burns

Aetiology

Depth

· Location

— Thick vs thin skin

· Temp @ location

· Duration of exposure

Type

1.       Thermal

2.       Electrical

Electrical flash burns: There is no conduction of current and so superficial burns

Contact burns due to ignition of clothing

Conductive burns due to passage of current from entry to exit point

The injury is determined by voltage, type of current and path of current.

The damage is the result of differential tissue resistance. Skin has low resistance and so relatively little damage. Underlying muscle, bone, nerve and vessels have much greater resistance and so damage.

· Areas of injury

— Nervous system

Immediate LOC, peripheral & spinal cord paralysis

Delayed Can take up to 3 yrs to evolve

Seizures, paralysis, headaches, depression, transverse myelitis, aphasia

— Bone

# 2° to tetanic contraction / falls

— Muscles & vessel

Muscle damage & necrosis

Rhabdomyolysis ± ATN

Compartment syndrome

Vessel thrombosis ® delayed necrosis (up to 10/7)

— Cardiopulmonary

Arrest Cardiac & respiratory (brain stem)

Arrythmia

Myocardial damage need 11-30,000 V

— Ocular

Cataract fromation

Management principles

Assess for other injuries caused by fall/LOC/tetanic muscle contraction.

· A – Airway management with cervical spine control

· B –

· C – monitoring and treatment of cardiac arrhythmia. More common in those who are acidotic or hyperkalaemic

· D – through neurological examination

· Extent of injury greater than suggested by BSA burn. Administer fluid to maintain UO >100ml/Hr

· Monitor ECG and electrolytes for hyperkalemia for arrythmia

· If a limb is swollen then check for fractures then prompt fasciotomy

· Necrotic tissue is debrided following conservative principles to save limb

· If evidence of myoglobinuria then: Alkalinize urine by adding 50mmol of Sodium · Barcarbonate to each 1L of fluid and maintain urine pH >7. Give mannitol 1g/Kg to maintain UO and act as a free-radical scavenger.

3.       Chemical

· Alkali or acid

· Acid

— more severe injury

— coagulation necrosis

— eschar formation

· Alkali

— more destructive

— liquefaction necrosis

— no eschar

Remove all clothing and shoes

Brush of all chemical powder before irrigation

After brushing off powder immediate and prolonged irrigation with water for 30 minutes with acid and 60 minutes with alkali

Phenolic acid must be irrigated with glycerol as it is not water soluble.

Physiology

· Microvascular and coagulation rxn in the surrounding tissue dermis

Increasing extend of injury

Larger injury can cause systematic response from this rxn due to loss of dermisàvasoactive mediatorsàinflammatory response or infection

--> Fluid loss from burn (partial>full)àodema

· Generalised oedema 2° capillary leak – increased microvascular permeability occurs within minutes to hours after injury

· Hypermetabolic status

Initial decrease in cardiac output and the metabolic rate output (ebb) in the first 12-36 hours from interstitial odema

Then doubling cardiac with ensuring circulatory hyperdynamism (flow). Accelerated gluconeogenesis, insulin resistance, and increased protein catabolism accompany this response.

— Full > partial

· Haemorrhage from other injuries

 

Mechanism of inhalational injury

· Heat damage to upper airway causing edema and obstruction

· CO poisoning

· Cyanide poisoning – cyanide gas released from burning of synthetic materials. Suspect whenever the CO level excess 10%.

· Inhalation of toxic smoke

Identification of inhalational injury

· Hoarseness of stridor

· Burns to face or oral mucosa

· Burns in an enclosed area

· Burns >50%

· Exposure to super-heated steam.

Vessel changes

· Full thickness

— Deep coagulation necrosis obliterates bv (? basal membrane)

· Partial thickness

— Hyperaemia & vasodilatation

· Cytokine mediated change in vessel permeability

— Systemic effects can ® SIRS

Zones

· Necrosis: Central coagulation of protein and cell death

· Surrounding stasis with decreased microvascular blood flow – tissue which is potentially dead depending on adequate perfusion, infection and desiccation.

· Peripheral hyperaemia

Evaluation

Extent

· Rule of nines – only second and third degree burns are included when determining the need and volume of fluid resuscitation.

— front and back of arm 9%

— front of leg 9%; back of leg 9%

— head front and back together 9%

— anterior torso 18%

— posterior torso including buttock 18%

— Perineum 1%

v In a child hand = 1%

Depth

Burn wounds deepen over 48-96 hours so a better idea of which areas need grafting comes with time.

The ability to visually determine a burn that will heal from dressing or not in the first day is poor (50% correct); the accuracy of clinical prediction improves to 90% on day 3-7 post burn.

· Superficial – epidermis only – first degree

— red, painful (like sunburn)

— Epidermis only

— will heal in 5-10 days without scarring

· Partial thickness of dermis (can be divided into superficial and deep partial thickness burns) – second degree

— blanch, painful, blistering, desiccation of skin occurs

—   Epidermis and some dermis – some epidermal skin appendages remain from which epidermis regenerates.

—   For superficial burns healing occurs quickly (2-3 weeks) with minimal scarring or pigmentation change; for deeper partial thickness burns healing is slower (3-4 weeks with hypertrophic scarring and unstable epidermis).

— Will declare themselves in a week.

— Depending on depth may need grafting

— Healing without grafting 2-6/52

· Full thickness – third degree

— white, insensitive, leathery texture, waxy

— Unless <2cm in diameter these burns require grafting for healing.

Initial Mx

A

· early intubation with burns to mouth, neck

· danger signs of

— soot @ back of mouth / round nose

— facial / neck swelling

— stridor

—   carbonaceous sputum

—   The classic physical signs have a poor predictive value in excluding or assuring the diagnosis of inhilational injury.

—   Brochoscopy is a reliable means of diagnosing inhilational injury: carbonaceous material, erythema, ulceration of mucosa and edema below the level of the true vocal cords suggest inhalational injury.

—   Bronchoscopy occasionally produces false negative results in the hypo-perfused and hypovolumaemic patient. Here 133Xe gas inhalation scan may be useful.

—   Mild inhalational injury is treated with humidified oxygen-enriched air and chest physiotherapy.

—   Severe injury requires ET intubation and regular pulmonary toilet.

—   Patients at risk should be started on 100% O2, carboxyHB levels checked and flexible bronchoscopy performed. Inhalational adrenaline treatment can be given. An ET tube is threaded over the bronchoscope and the patient intubated if erythema, oedema or blackened sputum is found

B

· risk of LRT burns – injury to lower airway caused by chemical irritants associated with combustion and closed space burns.

· warning of pulmonary oedema

· Ix

— CXR

— ABG

— Carboxyhaemoglobin levels for fires

· CO poisoning

— Pa02 & Sa02 may be normal

— Metabolic acidosis

— Assume CO exposure in ptys with burns in confined spaces

— Clinical

Headache, N&V, mental disturbances, cherry red lips

— Check Carboxy Hb level

³ 10% 100% O2

³ 20% IPPV 100% O2

— t1/2 CO

250 min room air

60min 100% O2; 45 min with 100% O2 and PEEP and 25 min in hyperbaric chamber

C

· Will require IV fluids if >12-15% burns

· 2 large bore cannulae in upper limbs avoiding full thickness burns

· NGT

· U+Es, FBC, Xmatch

· 1L of plasmalyte stat if evidence of shock

— p>120 BP<100

— 20ml/kg in children

· catheterize for >15% burns

D

· Drugs

— IV narcotics titrated against pain

— Tetanus prn

E

· Escharotomy circumfrential burns of limbs or trunk

— may require division down to including deep fascia to prevent tourniquet
- sites:

image

· Excision of certain chemical burns

— phosporus, chromic acid

Admissions

· ³ 10% burn

· burns to face, neck, perineum, hands, feet

· significant smoke inhalation (do CO-Hb levels)

· pain requiring narcotics

· threat of Non-accidental injury or self harm

Post-resuscitation

Fluids/Electolytes

First 24 hours

· IV fluids & IDUC for burns >15%

· Parkland formula 4 ml x kg x % burn (resuscitation)

— give 1/2 of deficit + maintenance in first 8hrs (from time of burn)

— give 1/2 of deficit + maintenance in next 16hrs

 

Or Children 3ml x kg x % burn for the lst 24 hour

the same principle applied for administration

the 0.5ml x kg x % burn for 2nd 24 hour resuscitation fluid + normal maintaince

 

· Fluid is Ringer’s lactate

· risk of hyperkalaemia

· adjust as per clinical progress

· Q4H biochemistry with burns > 20%

· risk of tubular blockage with haemoglobinuria/myoglobinuria

— maintain U/O @

0.5 – 1.0 ml/kg adults

1ml/kg in children

2.0 ml/kg neonates

— If UO ¯ then ­ rate do not bolus (risk of excessive tissue odema)

· 50ml of whole blood is required for each 1% BSA burn. Half in first four hours and remained in next 20 hours.

Second 24 hours

· Usually 5% albumin in normal saline is administered to aid correction of plasma volume deficit. This is required only with burns >30%BSA. This volume is infused at a constant rate over the second 24 hours. 5% Dextrose is administered to maintain urine output at 0.5-1ml/Kg/hr once the first 24 hours has elapsed.

· 30-50 % BSA: 0.3ml/kg/%BSA

· 50-70 % BSA 0.4ml/kg/%BSA

· >70 % BSA: 0.5ml/kg/%BSA

Respiration

· risk of ARDS

— Rx with ventilation and PEEP

— avoid sux (hyperkalaemia))

· ABG may show metabolic/respiratory acidosis

Dressings

Inital

· Initial wound care is a sterile sheet or surgical drape. Cling wrap can be used initially

Definitive wound care need not occur in the first 24 hours.

· Keep the environment to >90degrees F.

Escharotomy

· Circumfernetial full-thickness burns may impair the circulation of the underlying limb.

Oedema beneath the eschar impairs the circulation to underlying and distal tissues

· Circumferential truncal burns may impair chest wall movement and ventilation.

How do you assess the need for escharotomy in a circumferential burn?

· Repeated assessment in intervals of no less than one hour

· Progressive decrease of absence of pulsitile flow in the palmar arch and digital vessels with CW Doppler.

· Deep tissue pain, cyanosis, parasthesia, slow cap refill are hard to assess in the burnt limb

· The escharotomy is performed in OT without local or general anesthesia

· Incise first the mid-lateral aspect of the limb through the entire length of eschar.

· If pulsitile flow is not detected in 5 minutes then repeat on the mid-medial aspect of the limb.

· Incise just the eschar.

· Tuncal escharotomy: falling O2, rising CO2 or airways pressures (in the ventilated patient) and tachyponea and restlessness (in the spontaneously breathing patient) can all be indications of need for truncal escharotomy

· Bilateral mid-axillary incisions are performed and joined in the middle at the lower border of the costal margin. Transverse incisions at the upper sternal border and epigastrum can be added if the eschar extends on the abdomen.

 

Avoid long saphenous vein and PT artery

 

Avoid ulnar and radial nerve

 

Avoid common perineal nerve/sural nerve

 
 Description: fig16

 

Burn debridement

· Wound excision is required in deep partial thickness and full thickness burns

· This can be performed within 24 hours for small/moderate size burns (30%) but may be delayed for 4-10 days in the unstable frail or septic patient.

· Prompt burn wound excision and skin grafting reduces the length of hospital stay and period of rehabilitation

· Use a pneumatic dermatome to tangentially excise tissue to reach the deeper viable tissue.

· A: superficial partial thickness: Pass the pneumatic dermatome once to expose viable dermis with punctuate capillary bleeding

· B: Deep partial thickness: sequential passes of the dermatome are required to excise deeper burn wounds.

· C: Deeper burns can be excised with a scalpel down to the level of the deep fascia – a technique which reduces blood loss.

· Excise no more than 20% BSA in each theatre visit as this corresponds to circulating blood volume loss or 2 hours operating.

Blood transfusion is routinely required

· Wound coverage is generally best achieved with autologous SSG.

· SSG are harvested to a thickness of 0.008-.012 inches: the thinner the greater the take rate and the better the donor site recovery but the worse the recipient site cosmesis.

· Meshing at a ration of 1:1.5  to 1:4 is used. Mesh ratios greater than 1:4 required prolonged time for healing. The greater the mesh ratio the greater the take rate but the slower the healing.

· The excised wounds should be immediately covered with autologous skin if available

· If donor sites are insufficient then cadaver skin (human allograft), pig skin (procine xenograft) or biosynthetic products can be used (integra, transcyte or biobrane) can be used. Cultured autologous keratinocytes are being evaluated.

· The biological dressings prevent wound dessication, limit bacterial ingrowth, reduce evaporative water and heat losses, improve healing quality, reduce wound oedema, and promote wound regeneration.  

· These biological dressings provide wound coverage whilst donor site heals before donor site re-harvest can occur.

Definitive wound dressing

· Goals: aid healing and prevent wound infection which leads to sepsis.

· Patient is cleaned and showered. Residual damaged dermis and epidermis is removed and extent of burn is mapped with Lund and Browder chart.

· Superficial burns do not require dressing

· Some partial thickness and full-thickness burns to face and hands do not require dressings

· Typical dressing: Topical SSD (sulfa allergy, neutropenia, resistance of clostridia and certain gram negative bacteria), Adaptic, fluffed dry gauze (Velban) and elastic gauze Kerlix.

· Dressing changes should be performed when the dressing is soaked with excessive exudates or fluid.

· Other topical agents include sulfamylon (better penetration of eschar), silver-nitrate (Good antibacterial spectrum but requires continuous moistening and stains)

· Dressed areas should be monitored for signs of locally invasive infection (erythema or oedema of wound, black discolouration, separation of eschar, haemorrhagic discolouration of fat) and systemic infection (pyrexia, tachycardia and acidosis).

· Infecting organisms are initially gram positive (Staph or step) and then gram negative (kelsiella, proteus, coliforms, pseudomonas).

· Daily swabs can be taken from second degree burns. However this does not reliably differentiate infection from colonization.

· Biopsy from burn if colony count >105 bacteria/g tissue indicates invasive wound infection.

· Biopsy from tissue adjacent to burn is most reliable means of differentiating infection from colonization. If viable bacterial are found in adjacent viable tissue systemic antibiotic treatment is used often combined with sub-eschar antibiotic c lysis with a 20G spinal needle. The infected eschar is then excised and should be covered with an allograft or biological dressing to avoid wasting autograft skin on infected wound.

Anti-biotics: Vancomycin for early infections; Cipro or Gentamicin for infections after 7 days.

Antibiotics

· Tet tox

· systemic prophylaxis breeds resistance

· Culture every 48hrs

· if bug cultured then treat for only 4-5 days to prevent superinfection

Nutrition

· >20% burns consider feeding

Curreri formula: {25kCal × weight (Kg)} + {40kCal × % BSA burn}

Protein requirement is increased to 3g protein/Kg/Day

Metabolic requirements are increased in proportion to the size of burn, infection and environmental temperature.

Calorific requirements can be minimized by controlling infection, avoiding hypothermia and pain.

—   enteral preferable within 6hrs – most often naso-duodenal route.

—   If enteral feeding is not possible due to ileus or gastroparesis, Parenteral supplementation.

Recovery

· Wound contracture - physio

· Body image

· Psychological/Emotional support - support group

Risk of death from burn injury

· Three risk factors can be identified which weigh equally on risk of death:

l   %BSA >40%

l   age >60 years

l   inhalational injury

As the presence of these risk factors increases so the mortality increases:

0 risk factors – 0.3%;

1 risk factor 3%;

2 risk factors 33%;

3 risk factors 90%.

· If age + % BSA exceeds 100 then mortality will be 50%.


Skin Grafting

Donor sites
- pick for cosmesis, healing potential, intraop positioning, pain.
Set dermatome to 6/1000 - 12/1000 of an inch
- enough toget a #15 blade through the gap
Use mineral oil on skin to help gliding of dermatome
Watch carefully to ensure thickness is correct as you go.
- should have pink spot bleeding at good depth
 

Placement
- under a little stretch
- contact wound bed completely
- avoid meshing; seams become visible scars
- absorbable suture edges in children else however you like.
- foam stapling

Burns teams will apply judicious early excision and grafting to some deep wounds
- e.g. avoids wound hypertrophy, pain of dressings,