burns Flashcards
the burn injury is divided into 3 concentric zones
zone of coagulation,zoneof stasis, zone of hyperaemia
zone coagulation
area of necrosis
zone of stasis
area of ischaemia that is potentially salvageable with fluids.
zone of hyperaemia
increased blood flow
pathophysiology of burns
Release of inflmmatory cytokines as part of burn injury mediates altered permeability of the vasculature and allows escape of intravascular fluid.
This allows extravasation of proteins which further promotes loss of intravascular fluid.
This flow occurs over the first 36 hours post burn.
As the TBSA approaches 25% the level of fluid loss can cause a level of circulatory shock.
types of burns
Flame burns
Scalds
Chemical burns
Electrical burns
First degree burns
cause: sun, hot liquids,brief flash burns
Colour: pink or red
Surface: dry
Sensation: painful
depth epidermis
time of healing : a few days
second degree burn
cause: hot liquids, flash or flame
Colour: pink or mottleddred
surface: moist, weeping blisters.
sensation: very painful
depths: epidermis and portion of the dermis
healing time: one ormoreweeks
third degree
Cause: flame, prolonged contact with hot, liquid or object, electricity or chemical
colour: dark brown charred,pearly white
surface: dry and inelastric
sensation: anaesthetic
depth: epidermis, dermism deep structure
timr : healing by contraction
classification of burns
partial thickness (superficial), deep partial thickness, full thickness.
Signs of airway injury.
Signs of airway injury include :
(1) Singeing of eyebrow /nasal hairs
(2) Carbonaceous sputum
(3) Stridor ( may be a LATE finding!)
(4) Hoarseness
(5) History of burns within an enclosed space
(6) Neck swelling
Recall that presence of carbon monoxide within the blood will result in falsely elevated oxygen saturation readings. Co-oximetry is required for the monitoring of these patients.
In management of circulation, IVA should preferably be sited in areas of unburned skin, however if impossible, a burned area may be utilised.
what is the amount of urine that should be mad in a burn person
30 - 50ml/kg/hr
why should nasogastric tube placement
ileus may accompany major burns
in the rule of 9, all the body’s areas are 9 except
upper extremity which is 4.5
parkland formula
2-4ml * % burn sufface * body weight .
special rules for parkland formula
To be administered in the first 24 hours post BURN (NOT POST PRESENTATION!!)
- First half administered in the first 8 hours post burn
- Second half administered over remaining 16 hours post burn.
Why does Parkland’s Formula extend only for the 1st 24 hrs post burn?
Isotonic fluids, ideally Lactated Ringer’s to be used.
Fluid rate should be adjusted based on physiologic response i.e. urine output. ( it is only a GUIDE to fluid resuscitation)
other information for calculating fluids
There are several methods of calculating fluid resuscitation for infants and children. One method is to use Parkland Formula and modify it to maintain an hourly urine output of 1ml/kg/ h. Alternatively, a pediatric maintenance rate for 24 hours can be calculated and then an additional 2 to 4ml multiplied by percentage BSA burned can be added to the total. The entire amount if infused over the first 24 hours. In children weighing less than 25 kg, a urine output of 1ml/kg/hr is necessary (Tintinalli et al.)
Use of colloids for fluid resuscitation in burns has not been shown to improve outcomes and may actually complicate matters through causation of increased accumulation of water in the lungs and decreased glomerular filtration rate.
indication for admissions
1.Partial Thickness Burns with Total Burn Surface Area >10%
2.Burns to the hands, face, feet, genitalia, perineum or major joints
3.Circumfrentail burns
Those crossing major joints
4.Third and fourth degree burns
(7)Presence of comorbidities which could worsen outcome
(8)Concomitant trauma which could worsen outcome
(9)Suspicion of child abuse
(10)Burn injury patients who require special social, emotional or long-term rehabilitative intervention.
Electrical burns (including lightnng injury)
Chemical burns
Inhalation injury
complications of burns
Early: fluid loss and hypovolaemia, airway injury, pulmonary oedema, compartment syndrome
late: scarring, contracturs, infection, septicaemia, psychiatric
airway/ respiratory injury
(1) Supraglottic Airway Injury
The hot gases can physically burn the nose, mouth, tongue, palate and larynx . Once burned, the epithelium starts to swell and may completely block the airway.
(2) Airway injury below the level of the glottis
Rare, usually mediated by steam.
(3) Metabolic poisoning
(4) Inhalational injury
