BURNS
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njuries that result from direct contact or exposure to
any physical, thermal, chemical, electrical, or radiational source are termed
as Burns.
Ambroise pare (1510 – 1590) showed the technique for
early excision of burns wound.
1607 – G. F. Hildanus: showed the pathophysiology of
burns.
1842 – Curling showed the Gastric and Duodenal ulcers.
It is estimated that almost 2,65,000 deaths are occurring
every year because of burns. In India, approximately 70 lakh burns cases occur annually
out of which 1.4 lakh people die. 4/5th are women and children and
80% of the cases reported are because of domestic accidents (usually in the
kitchen).
Burns are classified:
On the basis of Cause –
1. Thermal
(scalding and flaming)
2. Electrical
(electric wires, power transmission lines and lightning)
3. Chemical
(acids and alkali)
4. Radiational
(alpha, beta, and gamma radiations)
5. Inhalational
On the basis of Depth –
1. Superficial
2. Partial
3. Full
thickness
Superficial burns – Painful, no edema, blanches with
pressure, redness.
Partial burns – Blistered, moist, painful.
Full thickness – Dry, discoloured, no pain.
Degrees of classification –
1. I
degree – Epidermis
2. II
degree – Epidermis + Dermis
3. III
degree – Epidermis + Dermis + Subcutaneous tissue
4. IV
degree – Above + Muscle/bones
Pathophysiology of burns –
1. Zone
of coagulation (seen in epidermis) – necrotic area with cellular disruption.
The tissue damage is irreversible.
2. Zone
of stasis (seen in epidermis) – Can survive or go into the coagulation zone.
3. Zone
of hyperaemia (seen in dermis) – Viable tissue, not in risk of necrosis.
Oedema in burns patient is biphasic in nature; where,
the 1st hour is marked as rapid increase and immediate oedema, and
later it gradually increases over the period of 12-24 hours.
Burn shock is another phenomenon occurring in cases of
burns where there is hypovolemia and rapid oedema formation. But this scenario
takes place only when the burn area is more than 1/3rd of Total Body
Surface Area (TBSA). Oedema in non- burnt tissue is because of loss of
capillary integrity and increase in intracellular sodium levels, leading to
water retention and oedema.
Inflammatory mediators –
1. Histamine
2. Serotonin
3. Thromboxane
A2 and B2
4. PGE2
5. PGI2
6. LTB4
and LTD4
7. Bradykinin
8. Free
radicles
9. Angiotensin
II and vasopressin
10. CRP
All of these, the irritation, cause Gastro-Intestinal
Ischaemia (reduction in flow of oxygen to GI), Reduce Blood Pressure, and sometimes
Pulmonary hypertension.
Hemodynamic consequences –
Reduced cardiac output leading to hypovolemia. Myocardial
dysfunction (probably because of O2 free radicals being delivered). Increased
vascular resistance and organ ischaemia, predominantly in Renal (kidney) and GI.
Since there is reduced blood supply to the kidney, the
urine output is reduced and this increases the chances of renal failure.
Also, GI ischaemia has its own consequences. There is
reduction in the absorption of glucose, amino acids, and fatty acids. Mucosa of
the intestine gets reduced in size leading to Mucosal atrophy, hence Curling’s ulcer
may occur.
Curling’s ulcer.
Immune system is also affected by this. There in
increased production of neutrophils which then reduces by 48 – 72 hours.
Macrophage production is also reduced.
The following things happen in the first 48 hours –
1. Reduction
in O2 consumption
2. Reduction
in Basal Metabolic Rate
3. Reduction
in Urine output
4. Reduction
in Cardiac Output
5. Impaired
Glucose tolerance with hypoglycaemia
Other things happening are –
1. Increase
in Urine cortisol
2. Serum
cytokines are increased
3. Increase
in serum catecholamines
4. Insulin
resistance is seen
5. Basal
energy expenditure is increased
All these hypermetabolic changes are increased in the
first 5 days that then stabilize to form a plateau stage.
Inhalational injuries are caused by –
1. Carbon
Monoxide
2. Hydrogen
Cyanide
3. Nitrogen
and its oxides
4. Aldehydes
and Acrolein (kerosene)
Carbon Monoxide is the most common gas to cause
inhalational burns and the notable effects are –
1. 20
– 30% concentration in blood causes throbbing headache in the temples
2. 60
– 70% concentration in blood leads to coma, convulsions, depression in cardiac
and respiratory functions.
3. 80
– 90% concentration in blood leads to death within 1 hour.
4. 90
– 100% concentration in blood leads to death within minutes.
In these types on burns there in excessive oedema in
the oropharynx and that leads to pneumonia, sepsis and death.
Evaluation of burns –
Wallace’s rule of 9 is followed –
a. Head
and neck - 9% [18%]
b. Upper
limbs – 2 x 9% [9%x2]
c. Lower
Limbs – 2 x 18% [14%x2]
d. Trunk
– 2 x 18% [36%]
e. Perineum
– 1%
[Brackets indicate the percentage of burns in babies]
Palm Method – Size of the patient’s palm = 1% of Total
Body Surface Area (TBSA).
MANAGEMENT OF PATIENTS –
Phase 1: Treatment at the scene and then transport to health
care facility.
Phase 2: Assessment and stabilization at the health
care facility, and then transport to burn ICU.
Pre-Hospital Management –
1. Rescuer
to avoid injuring himself.
2. Remove
patient from source of injury.
3. Stop
burning process.
4. Burning
clothing, jewellery, watches, belts, etc to be removed.
5. Pour
ample water on the burnt area.
6. Brush
skin if agent is powder.
7. Turn
off the electric current.
8. Separate
the patient from the source using a non-conductive object to prevent injury to
self.
Assess the A, B, C, i.e.
Airway, Breathing, and Circulation along with cervical
spine immobilization.
Respiratory tract gets oedematous very quickly so
ensure there is no obstruction and start 100% humidified O2 therapy.
Ice- or ice-cold water leads to vasoconstriction,
hypoxia and hypothermia further reducing the chances of recovery. Hence it should
not be used.
Do not apply toothpaste, lotions, powders, ghee,
butter or any other sticky solutions. Wrap the area with clean bandage or cloth
to prevent contamination and assess for any life-threatening injuries.
I.V. morphine is administered for pain relief and
relief of anxiety, avoiding any intramuscular or subcutaneous injections. Withhold
oral intake.
Start I.V. line (not required if the hospital is less
than 60 minutes away). Do a thorough head to toe examination.
RL infusions to be done in the following
concentrations –
1. Age
> 14 yrs = 500mL/hr
2. Age
6-14 yrs = 250mL/hr
3. Age
<6 yrs = 125mL/hr
At Hospital Management –
1. History
of incident
2. Physical
examination
3. Vitals
4. Pain
and or other symptoms are noted
5. Foleys
catheter is placed
6. NG
(Nasogastric Tube) is placed.
7. Removal
of pulmonary secretions
8. Bronchodilators
and mucolytics are administered
9. Escharotomy
may be required
Escharotomy is performed in cases of deep burns (2nd
or 3rd degree) where the main aim is to allow free movements of the
chest wall for respiration and establish circulation below the eschar to allow
its healing and reduce the swelling of rigid eschar. Antimicrobial prophylaxis
is given to prevent sepsis.
Escharotomy (done to prevent compartment syndrome post
burns)
Indication for admission in hospital –
1. >15%
of burns in adults
2. 10%
burns in children
3. Airway
or inhalational injuries
4. Extremes
of age
5. Suspected
non-accidental burns
6. Burns
that require surgery
7. Significant
burns on face, perineum, hands, etc
8. Severe
electric burns that may have serious sequalae.
Further treatment is based on severity of the burns.
This severity is determined by the depth of the burns, total body surface area
involved, age, site, and any associated injuries.
Baux score can be used to identify the probable
outcome.
Baux score = Age in years + % of TBSA.
Interpretation - <80 good
80 – 100 = Life threatening
>100 = BAD
The main goal for the first 24-48 hours is to maintain
vital organ function and perfusion.
Parkland Formula for administration for RL solution
(Ringer Lactate)
Parkland Formula = 4ml x %of burn x wt (kg).
1st ½ is given in 8 hours, the next ½ is
given over the next 16 hours.
[max applicable TBSA = 50%]
Other formulae used are –
Evans formula, Brookes formula.
For paediatric age group – Carvajal formula is used.
Assessment of fluid resuscitation –
1. Urine
output (adults >1mL/kg/hr)
2. Daily
weight
3. Vitals
4. Level
of consciousness
5. Laboratory evaluation values
For nutritional support, the estimated metabolic
requirement is done by Curreri formula.
Curreri formula = 25kcal x body wt + 40kcal x %BSA.
The diet should be high in calorie and protein with other
nutritional supplementation should be provided.
Wound management –
Frequently monitored for any infection and sepsis. Wound
culture samples are taken along with biopsies.
Shower on bed, by bed baths or water spray. Maintain
appropriate room temperature and humidity. Do not burst blisters, aspirate
them. Trim hair around the wound. Do not rub the wound for drying, pat the area
to absorb water.
Antimicrobial agents used –
1. Silver
sulfadiazine (0.5%)
2. Mafenide
acetate (5%)
3. Bacitracin
4. Nystatin
5. Polymyxin
B
6. Betadine
Debride the wound and close it by dressing.
Timing of surgery –
1. Urgent
surgery – High tension electrical injury. Deep encircling burns require
escharotomy.
2. For
small burns excision and grafting is done.
3. Tangential
burn excision with early split thickness skin grafting is also performed.
Skin grafts – are
of 2 types, Permanent and temporary.
Permanent are of further 2 types -
Autografts and Cultured Epithelial Autografts (CEA).
1. Autograft
– harvested from patients, non-antigenic, less expensive, decreased risk of infection,
can utilize meshing to cover the area, but is quite painful.
2. CEA
– used for limited sites, a small skin sample is taken from patient and is then
grown in lab which is later on used as a graft tissue, very expensive, skin
remains fragile and very poor cosmetic results are achieved.
Temporary skin grafts are of the following types –
1. Biosynthetic
– homograft/xenograft
2. Artificial
skins – Collagen based
3. Synthetic
– Biobrane/opsite
Complications –
1. Focal,
multifocal, generalized
2. Streptococcal,
staphylococcal or pseudomonas infection
3. Burn
sepsis in children
4. Necrosis
5. Unexpected
rapid eschar separation
6. Septic
lesions of unburnt tissue
7. Contracture
formations
8. Keloids
Burnt sepsis –
1. Temperature
of <36.5 or >39 degrees.
2. Progressive
Tachycardia (110 bpm and more in adults)
3. Progressive
tachypnoea (>25/min non ventilated and >12/min in ventilated)
4. Thrombocytopenia
5. Hyperglycaemia
6. Inability
to continue enteral feeding
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