Burns Flashcards
What are the bone zones?
- Zone of coagulation: area of maximum damage, irreversible tissue loss due to coagulation of proteins
- Zone of stasis: decreases tissue perfusion, tissue is possibly salvageable
- Zone of hyperaemia/ inflammation: adequate perfusion due to patent blood vessels
What are the types of burns?
- Thermal
- Chemical
- Electrical
- Radiation
What to ask when taking a burn hx
Explosion? Risk of blast injuries
Fire in enclosed space? Risk of CO poisoning/ smoke inhalation
What was the burning material? Burning plastics release cyanide
How long was patient exposed to fire and smoke
Loss of consciousness?
Fall to escape fire?
PMHx and tetanus status
Initial assessment following burns
ABCDE
Problems associated with burns
- Airway burns: suggested by hoarseness, stridor, dysphagia, facial and mouth burns, singed nasal hair, soot in nostrils or palate
- Spinal injury: seen in blast injuries or those who have jumped to escape buildings
- Breathing problems: contracting full thickness circumferential burnt of the chest wall may restrict breathing due to lack of movement
- Circulatory problems: hypovolaemic shock is a feature of severe burns
ABCDE in burns
Airway: consider burn of airway in setting of facial burns, eyebrows singed, carbons deposites, carbonaceous sputum, explosion with burns to head or torso
- Do we need to intubate? Hoarse voice, stridor - indications for immediate intubation because the airway will close very quickly, aim is to avoid need for surgical pathway
Breathing : as for other major trauma attach oximeter, listen to chest, exclude traumatic chest injuries
Circulation: cap refill, BP, IV access
Disability: AVPU, BM, pupils, analgesia (IV)
Exposure: document burn depth and area, cover burn, keep patient warm
How do we stop the burning process?
Remove clothing
Remove chemicals
Rinse with water +++
Keep patient warm
What is the parkland formula?
Used to calculate the total fluid requirement in 24hrs
4ml fluid x total burn surface area (as a % of total) x kg
1/2 fluid given in first 8hrs
1/2 given over next 16hrs
Example
Patient has burns to 30% body and weighs 75kg
= 4ml x 30 x 75
=9000mL or 9L
Therefore: 4.5L given during first 8hrs
4.5L given over next 16hrs
What is a superficial burn?
AKA 1st degree, epidermis only
What is a superficial partial thickness burn?
AKA 2nd degree burn
Affects epidermis and dermis
What are deep partial thickness burns?
AKA 2nd degree
Affects dermis
What are full thickness burns?
AKA 3rd degree
Full thickness - hypodermis
Describe a superficial/ 1st degree burn
Brisk bleeding on pinprick
Painful
Red but no blisters
Blanches when pressed, colour returns quickly
Describe a superficial partial thickness burn
Brisk bleeding upon pinprick
Painful
Pale pink, glistening, blisters
Blanches when pressed, colour returns slowly
Describe a deep partial thickness burn
Delayed bleeding following pinprick
Dull sensation - not pain
Cherry red colour
Does not blanch
Describe a full thickness burn
No bleeding upon pinprick
No sensation
Dry, why, leathery appearance
Does not blanch
Acid vs alkali burns
Acid burns are less dangerous
Acid burns: form a coagulation necrosis and the burns tend to form a hard layer and stop burning
Alkali burns: form liquid necrosis and continue burning
Important to remember regarding electrical burns
Can look small from the outside but deep muscle necrosis and myoglobin release can occur
Important to monitor ECG
Indicators of NAI burns
Hx not consistent
Lines of demarcation
No splash marks
Sparing of flexor creases
Delayed presentation
Attributing injury to another child
Uniform burn depth/ full thickness
Systemic pathophysiology of burns
Release of inflammatory mediators at the site of injury has a systemic effect if the TBSA is 20-30%
Cardiovascular changes: capillary permeability is increased >> loss of intravascular protein >> fluid in interstitial compartment >> myocardial contractility decreased >> hypotension occurs >> possible end organ hypoperfusion
Respiratory changes: inflammatory mediators cause bronchoconstriction and ARDS can occur
Metabolic: basal metabolic rate increases up to 3x - combined with splancnic hypoperfusion warrants early and aggressive neteral feeding to decrease catabolsim and maintain gut integrity
Immunological changes: non-specific down regulation of immune response
When are burns classified as severe?
When >10% BSA affected in children
When >15% BSA affected in adults
Are epidermal burns/ 1st degree burns included when calculating size of burn?
No
How to work out how much BSA affected by burn
Lund Browder chart
Or
Mersey burns app
Or
Rule of 9s:
Head = 9
Arms = 9%
Legs = 18%
Torso = 18%
Back = 18%
Genitals = 1%
How can the depth of a burn be assessed?
- Epidermal burn: skin is red and painful but not blistered - think sunburn
- Superficial partial thickness burn: epidermis and dermis affected, skin is pale pink and painful with blistering, capillary refill - blanches and rapidly returns
- Deep partial thickness: epidermis, upper and deeper layers of dermis, skin appears dry or moist, blotchy and cherry red, may be painful or painless, may be blisters, capillary refill - blanches with a sluggish return or does not blanch
- Full thickness: burn extends through all layers to subcutaneous tissues, skin is dry and white/ brown/ black with no blisters, leathery or waxy, painless, capillary refill - does not blanch
Rule of 5s when calculating burns
Used to quickly estimate burn surface area in children
Head = 20%
Earm arm = 10%
Each leg = 20%
Front of trunk = 10%
Back of trunk = 10%
Pre-hospital first aid measures for burns
- Remove patient from burning environment
- If clothes smouldering apply cold water and remove, unless they are stuck
- Provide high flow oxygen
Major burns resuscitation
Airway + c-spine: treat obstruction, immobilise neck if any possibility of c-spine injury, any evidence of impending airway ovstruction immediately call in order to allow for urgent GA and tracheal intubation
Analgesia: IV access (2x wide bore cannulae), send blood for cross match, U&E, glucose and coagulation, provide analgesia (IV morphine) + anti-emetic
Fluids: follow parkland formula 0.9% sodium chloride (4mlxTBSA%xkg) & give 1/2 during 1st 8hrs, check vitals every 10-15mins
Urinary catheter : satisfactory output = >50mL/hr in adults
Full thickness burns across >10% may require red cell transfusion
Breathing: check for COHb (carboxyhaemaglobin in blood) and ABG, full thickness chest burns require escharotomy, obtain CXR
Management of burn area
Measure area as % of TBSA
Irrigate chemical burns with warmed water
Cover burn with cling film or dry sterile sheets - not to be dressed until seen by specialist
Involve burns specialist early on
Ensure tetanus prophylaxis
Patient has been in a fire where plastic was burning - what do we do?
Burnt plastic = cyanide release
Give dicobalt edetate - the antidote
Most common cuse of inhalation injury
Smoke inhalation due to house fires
Common components of inhalation injury
- Direct thermal injury
- Soot particles causing damage to cilia + obstruct small airway
- 85% fire deaths are due to carbon monoxide
- Gas products of combustion: some react with water and cause strong acids which can damage resp tract
Clinical features of smoke inhalation
Confusion, loss of consciousness, oropharyngeal burns, hoarseness, loss of voice, signed nasal hairs, soot in nostroils/ sputum, wheeze, dysphagia, drooling, stridor
First aid measures for smaller burns
Separate patient and burning agent
Cool affected area with lots of cold water
*Be aware of hypothermia in infants and young children
Which organisation can search for an appropriate bed for a burns patient?
National burns bed bureau
Which patients to refer to a burns specialist
- Airway burns
- Significant full-thickness burns, especially over joints
- Burns >10% TBSA
Significant burns of special areas e.g. hands, face, perineum, feet
Recommended covering of burns on the hands
Cover with soft parrafin inside a polythene bag or glove sealed at wrist & change after 24hrs
Elevate to minimise swelling
Ideal burns dressing
Sterile +non-adherent
Dressings often need to be changed after 48hrs due to accumulation of fluid - if patient has been discharged this is done at GP
