ABC of Burns Flashcards
(117 cards)
1
Q
What are the 5 types of burns?
A
Scalds Thermal Electrical Chemical Radiation
2
Q
Define scald
A
Wet heat burn
3
Q
Define thermal burns
A
Dry heat burns, result from direct contact with flames/hot appliances
4
Q
What does the severity of a chemical burn depend on?
A
Type of chemical Concentration of chemical Contact time Quantity Surface area Ease of absorption Systemic effects Temperature
5
Q
What are radiation burns caused by?
A
Exposure to sunlight or sunbeds
6
Q
What are the depths of electrical burns dependent on?
A
The energy transfer to the tissues (depends on voltage, contact time and factors lowering resistance to current, e.g. skin moisture)
7
Q
Define a burn
A
A dynamic wound, that changes over time and is subject to the effect of secondary injury or external factors
8
Q
What is Jackson’s burn model?
A
Describes the areas of tissue in a burn and how they are affected
9
Q
What are the layers in Jackson’s burn model?
A
Area of coagulative necrosis
Zone of stasis
zone of hyperaemia
10
Q
What occurs in the area of coagulative necrosis?
A
Direct transfer of heat to tissue and an inability to conduct heat away rapidly enough leads to immediate coagulation of cellular proteins leading to their death
11
Q
What occurs in the zone of stasis?
A
Less damaged tissue in which inflammation occurs and vascularity is impaired leading to tissue ischaemia
Damaged but potentially viable (if adequate steps not taken, e.g. fluid resus, may become zone of necrosis)
12
Q
What occurs in the zone of hyperaemia?
A
Caused by release of inflammatory mediators from damaged tissue
Characterised by reversible increase in blood flow and inflammation
Once inflammatory response resolves, region returns to normal
13
Q
What is defined as a significant burn injury?
A
20-25% TBSA
14
Q
What can occur in a significant burn injury?
A
Alterations in the function of almost all the organs
Leads to release of inflammatory mediators from damaged tissue and neural stimulation
15
Q
What vascular changes do burns cause in the body?
A
Losses of fluid, e.g. weeping from partial thickness burns
Widespread changes - vasodilation + increased capillary permeability –> loss of protein + fluid –> hypoperfusion –> cell death (due to hypovolaemia shock)
16
Q
Why is early correction of hypovolaemia essential in burns management?
A
To prevent hypovolaemic shock and cell death
17
Q
How can the kidneys be affected by a significant burn?
A
AKI can result due to hypovolaemia, release of Hb from haemolysed cells and myoglobin from damaged muscle
18
Q
What is meant by the body entering a hypermetabolic state after a significant burn?
A
Secretion of stress hormones - cortisol, glucagon, catecholamines and suppression of anabolic hormones (e.g. insulin, GH) to mobilise amino acids to begin repair of tissues
Leads to profound catabolic state and muscle breakdown
19
Q
Why do burns patients become immunosuppressed?
A
Due to release of cortisol
20
Q
What are the complications of burn wound infection?
A
Delayed healing
Increased scarring
Bacteraemia, sepsis
21
Q
What are the most common pathogens of burn wounds?
A
Bacteria and fungi (often commensals)
22
Q
When do burn injections most commonly occur?
A
After 48-72h after injury
23
Q
What can the systemic inflammatory response post-burn cause in the lung?
A
ARDS
24
Q
Which GI condition is common in burns and what drug is given prophylactically to prevent it?
A
Stress ulcers, PPIs
Also gastroparesis isn’t uncommon
25
What are some long term sequelae from having a large burn?
Changes in overall growth and development
| Contractures etc.
26
How can long term sequelae of burns be prevented?
Correct posture, splinting, early physio
Mobilising
Surgical management of contractures etc.
27
What history should be taken from a burn patient?
```
Time of injury
Circumstances
First aid received
Analgesia taken
Date of last tetanus jab
Relevant illnesses, e.g. DM
Relevant drugs, e.g. steroids, warfarin
Allergies to dressings, antibiotics etc.
```
28
What is the order you should follow when treating burns victims?
First aid
Primary survey
Secondary survey
29
What does first aid of burns involve?
Stopping the burning process (e.g. extinguishing flame, irrigation if chemical)
Hold region under water for 20m
Wrap clingfilm around wound to travel to hospital
30
What is the ideal temperature of water to run over a burn?
15C
31
Why is running cool water over a burn important?
Reduces inflammatory reaction so can stop procession of necrosis into zone of stasis
Effective analgesic
32
What should you be careful of when running cool water over a burn?
The patient becoming hypothermic
33
Why should you not use ice or iced water to cool a burn?
Extreme cold leads to vasoconstriction which may deepen tissue injury
34
What is involved in the primary assessment of a burn?
ABCDEF
A - airway + cspine control
B - breathing
C - circulation + haemorrhage control (direct pressure to bleeding wounds), pulse, cap refill, insert 2 large bore cannulas, catheterise patient
Also take bloods (UE, FBC, clotting, glucose, group and save/cross match and carboxyhaemoglobin), ABG
D - disability ,AVPU/GCS
E - exposure + environmental control (remove all clothing etc., keep warm, log roll patient onto back)
F - fluid resus
35
What does AVPU stand for?
A - patient is Awake
V - patient responds to Verbal stimulation
P - patient responds to Painful stimulation
U - patient Unresponsive
36
If you cannot insert two large bore cannulae into a burns patient what should you do?
Insert a central venous line or get intrasseous access
37
What formula should you use to calculate how much fluids to give burns patients in the first 24 after injury?
Parkland formula
38
What other investigations/immediate management may you consider in a burns patients?
X-Ray - chest, pelvis, lat c spine
Analgesia - IV morphine best
Tetanus immunisation
Antibiotics
39
What is involved in the secondary survey?
```
AMPLE
A - allergies
M - medications
P - past illness
L - last meal
E - events/environment related to injury
```
Check MSK, neurological Ex, check head, face, abdomen chest etc.
40
What are the different categories of burn depth?
Superficial (1st degree)
Partial thickness/deep dermal (2nd degree)
Full thickness (3rd degree)
41
What area of skin do superficial burns affect?
Epidermis + superficial layer of the dermis (papillary dermis)
42
What is the appearance of a superficial burn?
Red and blistered
| Normal capillary refill
43
Are superficial burns painful and why?
Yes - due to exposure of sensory nerve endings
44
How long do superficial burns take to heal?
14 days
45
How do superficial burns heal?
By epithelialisation
46
What kind of scar do superficial burns leave?
Don't scar
| Just leave a colour match defect
47
What area of skin do partial thickness burns affect?
Epidermis and reticular dermis
48
What do partial thickness burns appear like?
Areas of necrosis and blisters may be seen
Capillary refill time diminished/absent
Sensation to pinprick lost
49
Why is the capillary refill time prolonged in partial thickness burns?
The burn has destroyed the dermal vascular plexus
50
Why is sensation to pinprick lost in partial thickness burns?
Dermal nerve endings are destroyed by the burn
51
How should you manage a partial thickness burn?
Dressed with antibacterial dressing and referred to burn surgeon
52
How deep are full thickness burns?
Destroy epidermis and dermis and may even penetrate into underlying structures
53
What is the appearance of a full thickness burn?
Waxy, white or charred
Skin looks shiny
Loss of sensation
54
What is the coagulated dead skin of a full thickness burn called?
Eschar
55
Are full thickness burns painful? Why?
No - nerve endings are destroyed by the burn
56
Why is it important to estimate the area covered by the burn?
Mortality is related to %TBSA and age of patient
57
What is the most accurate way to calculate %TBSA?
Lund-Browder chart (remember not to include areas of erythema)
58
What may be used to calculate %TBSA in an acute setting?
Wallace's rule of 9s (head, each arm 9%, chest, back, each leg 18%, perineum and hands 1%)
Paediatric rule of 9s
59
What is Parkland formula?
Volume of fluid = 4ml x %TBSA (up to 50%) x wt (kg)
Give first half in first 8h and last half in next 16h from injury
60
When are resus fluids recommended for a burn?
%TBSA >10% in kids, >15% in adults
61
What should you do if giving a patient fluids for a burn?
Catheterise to ensure adequacy of fluid resus
62
How do you calculate fluid resus for burns in kids?
Parkland formula expect 2ml instead of 4ml + paediatric maintenance fluids
63
How do you calculate paediatric maintenance fluids?
Normal saline (+/-5% dextrose to prevent hypoglycaemia):
100ml/kg up to 10kg +
50ml/kg from 10-20kg +
20ml/kg for each kg over 20kg
64
What ways can you monitor fluid resus?
```
Catheter
Central venous line
BP
HR
ABG
```
65
What urine output should you aim for in adults when giving resus fluids?
0.5ml/kg/hr (if over 50kg)
66
What urine output should you aim for in kids (<50kg) when giving resus fluids?
1ml/kg/hr
67
What things on ABG may indicate inadequate tissue perfusion?
pH <7.35
| Raised lactate
68
By how much does an inhalation injury increase the mortality rate?
40%
69
What is an inhalation injury?
Damage caused to the lungs by inhalation of various products of combustion, may also result in systemic absorption of harmful products
70
What are the symptoms of an inhalation injury?
SoB, wheezing, brassy cough, hoarse voice
71
What are the signs of an inhalation injury?
```
Soot in oral/respiratory secretions
Burns around face/mouth
Altered consciousness
Increased RR/effort of ventilation
Stridor
```
72
What are the three types of inhalation injury?
Supraglottic (above larynx) - thermal injury to airways due to inhalation of hot gas --> release of inflammatory mediators --> oedema and ventilator obstruction
Subglottic (below larynx) - chemical injury to alveoli
Systemic (absorption into systemic circulation)
73
What are the two most important substances implicated in inhalation injuries?
CO
| Cyanide
74
How can CO cause inhalation injuries?
It diffuses rapidly into the bloodstream and combines with Hb with an affinity of 240x of O2 to produce carboxyhaemoglobin
75
Burning of what materials produces cyanide?
Certain plastics
76
What features result from cyanide poisoning?
Loss of consciousness
Neurotoxicity
Convulsions
77
What is the management of inhalation injuries?
Humidified oxygen 15L/min via non re-breathing mask
Monitor sats continually
Involve senior and anaesthetist
78
What is the burns referral criteria for referral to a burns specialist centre?
%TBSA - 2% in kids, 3% in adults
Site - consider if face, hands, feet, perineum, genitals
Mechanism - NAI, consider if electrical/friction/cold burn
Burn depth - full thickness, circumferential
79
What immediate surgery may be used in burn victims?
```
Escharotomy
Fasciotomy
Debridement of devitalised tissues
Necrectomy of burn area
Dermo-epidermal graft
Local flap
```
80
What is an escharotomy and why might it be necessary?
Dry eschar can act like a tourniquet and may constrict a patients neck or chest or circulation in fingers
As oedematous tissue swells, the eschar around it is rigid and cannot expand
Escharotomy may be necessary to aid respiration/prevent limb ischaemia
81
What surgery might be done a little later on?
Excision on non-viable skin
| Skin grafting
82
What late surgeon may be performed on burn victims?
Release of contractures
| Post-burn reconstruction
83
What is tangential excision?
Shaving away layers of skin until you reach viable/bleeding tissue
84
What is the major issue with tangential excision?
Blood loss
85
While burn patients are undergoing surgery, what other things should you try and do?
Monitor core temp to prevent hypothermia
Avoid hypo/hypervolaemia
Minimise blood loss
86
What causes electrical burns?
Generation of heat caused by the resistance of tissues to current of flow
87
How are electrical burns categorised?
Low voltage - below 1000V
High voltage - above 1000V
Lightening injuries - very high voltage
88
The amount of heat generated by a tissue during an electrical burn is directly proportional to what?
Amount of current, tissue resistance and duration of contact
Amount of tissue damage also depends on surface area contact and pathway through the body
89
List the tissues in the body in order of least to most resistant to electrical energy
```
Nerve
Vessels
Muscle
Skin
Tendon
Fat
Bone
```
Tissues with the lowest resistance sustain the most damage
90
What additional things are involved in the management of an electrical burn?
Turn off power supply etc.
Electrical discharge may affect medulla and so risk of cardiac arrest - CPR is essential initially and ECG should be obtained and monitored for at least 24h followed injury
91
How are the chemical agents causing burns roughly categorised?
Acids
| Alkalis
92
What kind of injury does an acid cause?
Coagulative necrosis
93
What kind of injury does an alkali cause?
Liquefactive necrosis
94
Why should you not use a neutralising agent when managing chemical burns?
Exothermic reaction when applied will produce heat and lead to further damage
irrigation is mainstay
95
What are common acids causing chemical burns?
Sulphuric, nitric, hydrochloric, hydrofluoric
96
What are common alkalis causing chemical burns?
Sodium, potassium hydroxide, wet cement
97
If a burns patient is still really dehydrated after resus fluids what can you do?
Fluid challenge (250-500ml fluid over 15-30m)
98
What source has the most up to date information on burns?
COBIS - care of burns in Scotland
99
What is the modified parkland formula (as used to calculate resus fluids in paediatric burn vitcims)?
total vol. Hartmans = %TBSA x wt (kg) x 2
After 8h, next 16h calculated as:
hourly rate of albumin 4.5% = %TBSA x wt (kg) x 0.1ml
100
What is the most common cause of burns in adults?
Thermal
101
What are the most common cause of burns in kids?
Scald
102
What do you see on ABG with CO poisoning?
Metabolic acidosis
103
What fluid is mostly used in burns fluid resus?
Human albumin
104
What is the Muir and Barclay formula?
%TBSA x body wt x 2
Gives fluid loss due to burn, must give additional fluid to cover normal daily losses
105
In a child who has a major burn, after giving them fluids and inserting a catheter what else should you do?
```
Talk to parents
Give IV analgesia
Establish tetanus immunisation status
Send off baseline bloods
Insert a NG tube
Continue O2 therapy
```
106
What bloods should you send off for a major burn?
Haematocrit - if high, needs more fluid
Group and save 0 in case need a transfusion
UE - check renal function okay
107
Will partial thickness burns heal on their own?
Yes
108
What things will reduce the chance of a skin graft taking?
Infection, haematoma, shearing forces on the graft
109
Why should burned areas be covered whilst outside for up to 2 years post-burn?
Burn scars are very sensitive to sunshine while they mature
110
What are some common post-sequelae problems in kids after they have a major burn?
```
Hypertrophic scarring
Sensitivity to sunburn
Contractures
Further wound breakdown
Further burning
School problems
Nightmares
```
111
What is hypertrophic scarring?
Thickened, red, itchy scars
112
What things might you like to elicit in the history about the circumstances of his injury?
Open vs closed fire place
Duration of exposure to smoke before being rescued
Jumping/falling while escaping from fire
Collapse of furniture or building structures on the victim
Explosions/blasts
Electrical injuries
Protective equipment
113
How does cyanide cause poisoning?
Interferes with mitochondrial respiration
114
What is involved in the management of suspected inhalation injury?
```
CXR
Analgesia
Bronchoscopy
Humidified O2 via non-rebreath mask 15L/min
Monitor sats continuously
Large IV bore access
Alert anaesthetist
Order CO level
```
115
What is the standard treatment of CO poisoning?
100% O2 via tight fitting mask
116
What is the most effective treatment of CO poisoning?
Hyperbaric oxygen therapy in a hyperbaric chamber
117
If a patient comes in with a burn and is not immunised against tetanus what should you give them?
3 dose course of absorbed vaccine + human tetanus immunoglobulin
