Burns
Last updated 11th August - Tom Heaton
Burns can be a very challenging presentation to manage, although the spectrum of injury can be very variable.
These notes will focus more on the critically ill/severely burned patient.
Much of them will also focus on the management of thermal and flame type burns, which are more common, with more specific discussion of less common burns e.g. chemical, elsewhere.
This is an excellent podcast from the guys at the Resus Room: https://theresusroom.co.uk/burns-2/
These notes will focus more on the critically ill/severely burned patient.
Much of them will also focus on the management of thermal and flame type burns, which are more common, with more specific discussion of less common burns e.g. chemical, elsewhere.
This is an excellent podcast from the guys at the Resus Room: https://theresusroom.co.uk/burns-2/
Classification
A burn is defined as “an injury to tissues occurring from exposure to heat, cold, chemicals, friction or radiation”.
Burns may occur from several different sources:
Burns may occur from several different sources:
- Thermal
- Flame
- Scalds
- Cold
- Flame
- Chemical
- Electrical
- Radiation
Pathophysiology
The tissue injury that occurs from the burn leads to an inflammatory response, which can be significant in large burns with lots of cellular damage.
This is similar to other SIRS pathology, with increased production of a number of pro-inflammatory mediators with their well recognised systemic effects:
There are a number of different adverse effects arising from the subsequent loss of skin function that occurs from significant burns.
Inhalational injury is an important factor in major burns and is covered in more detail here.
This is similar to other SIRS pathology, with increased production of a number of pro-inflammatory mediators with their well recognised systemic effects:
- Increased vascular permeability
- Generalised oedema
- Initial decrease in cardiac output and increase in SVR
- Hypermetabolic state (up to 2-3 times baseline) with catabolic state
- Immunosuppression
There are a number of different adverse effects arising from the subsequent loss of skin function that occurs from significant burns.
- Impaired thermoregulation
- Increased insensible fluid losses
- Loss of protective dermal barrier function
Inhalational injury is an important factor in major burns and is covered in more detail here.
Presentation
A lot of important information can be gained from the presentation.
This may radically alter a management strategy.
Key things that can be obtained include:
Mechanism of injury
As much detail about this should be obtained:
Medical Background
This may need to be obtained early.
Sources
There may be a need to obtain history from sources other than the patient about the nature of the events.
Consider the paramedics, fire crews, relatives, coworkers (e.g. if industrial).
This may radically alter a management strategy.
Key things that can be obtained include:
- Other trauma - the burn may be part of a larger trauma mechanism
- The type of burn - these may be managed very differently
- Risk factors for specific additional features - e.g. risk of inhalational injury.
Mechanism of injury
As much detail about this should be obtained:
- Mechanism of trauma
- As part of other trauma? e.g. RTC
- Potential injuries from escaping fire? e.g. jumping out of window
- Location of trauma
- Inside house vs outside?
- Nature of burning material? - toxicity risk
- Industrial injury?
Medical Background
This may need to be obtained early.
Sources
There may be a need to obtain history from sources other than the patient about the nature of the events.
Consider the paramedics, fire crews, relatives, coworkers (e.g. if industrial).
Assessment
Prior to assessment, it is important to remember that personal protection may be more relevant in these cases than in some other presentation.
Chemical burns are particularly relevant from this perspective.
In general, assessment will be guided by the severity of the burn.
Minor, peripheral burns may be reviewed on a history, examination, investigation pattern.
More serious injuries are best approached using that as for a major trauma i.e. an A to E assessment, preferably in parallel as part of a team.
Airway and Cervical spine protection & Breathing
It is important to remember that burns may be in addition to, and even masking, other traumatic injuries.
Cervical spine precautions are therefore essential to consider.
High flow oxygen should be administered to almost all of these patients initial, as there is a significant risk of hypoxia in this cohort.
The assessment of inhalational injuries is covered in more detail here.
Consideration will need to be given to:
Additional features of respiratory assessment should consider:
Circulation
This should involve a standard assessment of CVS stability.
Large bore IV access should be obtained - this may be more difficult if there have been significant burns to usual cannulation sites.
Ideally IV access should be through intact skin (potentially not always feasible initially).
Hypovolaemia from burns does not occur very early (i.e. during the initial presentation).
In cases of early CVS compromise, consideration should primarily be given to other trauma as the cause e.g. haemorrhage.
Disability
This should be carefully assessed.
An altered conscious level can point to important differentials e.g. traumatic brain injury, systemic poisoning.
A gross neurological exam may also help in this regard.
There may be overlap with CNS acting drugs and the cause of the fire e.g. alcohol.
Pain should be effectively and promptly treated.
Exposure
This is a crucial step.
Full assessment of the extent of cutaneous burn should be made at this time (see below) - this includes the back, which may require log rolling.
The patients clothes will need to be fully removed, taking care as some adhesion to skin may occur with significant burns (in this case cut around the adherent parts).
Jewellery (rings, watches) should be removed early, as swelling may lead to problems.
Patients must be kept warm, as temperature homeostasis is severely compromised in major burns, and treatment (cooling the burns) can rapidly drop core temperatures.
Secondary Survey
After the initial primary survey, a careful secondary survey is essential to identify other potentially important features.
Chemical burns are particularly relevant from this perspective.
In general, assessment will be guided by the severity of the burn.
Minor, peripheral burns may be reviewed on a history, examination, investigation pattern.
More serious injuries are best approached using that as for a major trauma i.e. an A to E assessment, preferably in parallel as part of a team.
Airway and Cervical spine protection & Breathing
It is important to remember that burns may be in addition to, and even masking, other traumatic injuries.
Cervical spine precautions are therefore essential to consider.
High flow oxygen should be administered to almost all of these patients initial, as there is a significant risk of hypoxia in this cohort.
The assessment of inhalational injuries is covered in more detail here.
Consideration will need to be given to:
- Inhalational thermal injury - usually upper airway
- Inhalational non-thermal injury - usually lower airway
- Systemic toxicity e.g. CO, cyanide
Additional features of respiratory assessment should consider:
- Encircling deep thoracic burns - may restrict ventilation
- Blast injuries - may result in pneumothoraces
Circulation
This should involve a standard assessment of CVS stability.
Large bore IV access should be obtained - this may be more difficult if there have been significant burns to usual cannulation sites.
Ideally IV access should be through intact skin (potentially not always feasible initially).
Hypovolaemia from burns does not occur very early (i.e. during the initial presentation).
In cases of early CVS compromise, consideration should primarily be given to other trauma as the cause e.g. haemorrhage.
Disability
This should be carefully assessed.
An altered conscious level can point to important differentials e.g. traumatic brain injury, systemic poisoning.
A gross neurological exam may also help in this regard.
There may be overlap with CNS acting drugs and the cause of the fire e.g. alcohol.
Pain should be effectively and promptly treated.
Exposure
This is a crucial step.
Full assessment of the extent of cutaneous burn should be made at this time (see below) - this includes the back, which may require log rolling.
The patients clothes will need to be fully removed, taking care as some adhesion to skin may occur with significant burns (in this case cut around the adherent parts).
Jewellery (rings, watches) should be removed early, as swelling may lead to problems.
Patients must be kept warm, as temperature homeostasis is severely compromised in major burns, and treatment (cooling the burns) can rapidly drop core temperatures.
Secondary Survey
After the initial primary survey, a careful secondary survey is essential to identify other potentially important features.
Burn Assessment
This has two main components:
Extent of Burn
There are several methods for estimating the TBSA that has been burned:
The rule of nines is a relatively simple method that can allow decent estimations of TBSA in the case of relatively large burns.
It works by allocating 9% (or factors of) patches of skin to different parts of the body:
Due to the different proportions in children, different values are used.
Similar problems may arise from the different body shapes of adults e.g. obese patients.
The 1% rule is useful for assessing smaller areas of burn.
It states that the palmar surface of the patient’s hand, including the digits with the fingers spread apart, is equivalent to 1% of the TBSA.
This is less accurate in patients with a higher BMI.
The Mersey Burns app is a very useful tool for calculating the TBSA (as well as other aspects of burns management).
https://merseyburns.com/
The app allows the area that is burnt to be coloured in on a chart, and will then calculate the TBSA.
Challenges with ascertaining the extent of the burn may also include the fact that some features of the burn may be dynamic.
Blisters may develop, or erythema may improve, changing the proportion of skin that should be included in the TBSA calculation.
Depth of Burn
The severity of the burn, in relation to its depth, is another essential part of the assessment.
Burns can be described as:
Superficial burns only involve the epidermis.
It is essentially equivalent to sunburn.
Partial burns are divided into superficial partial, which involve the epidermis and the upper layers of the dermis, or superficial deep, which extend into the deeper layers of the dermis.
Deep burns include all layers of the dermis and may include the underlying tissue.
These are classically described as painless (because of the destruction of skin nociceptors) but pain may still be present in nearby tissue that doesn’t have deep burns.
- Extent of burn - described by total body surface area (TBSA)
- Depth of burn
Extent of Burn
There are several methods for estimating the TBSA that has been burned:
- The rule of nines
- The 1% rule
- Mersey burns app
- Lund and Browder chart
- Serial halving method
The rule of nines is a relatively simple method that can allow decent estimations of TBSA in the case of relatively large burns.
It works by allocating 9% (or factors of) patches of skin to different parts of the body:
- Head and neck - 9%
- Upper limb - 9% each
- Lower limb - 18% each
- Front of trunk - 18%
- Back of trunk - 18%
- Genitalia - 1%
Due to the different proportions in children, different values are used.
Similar problems may arise from the different body shapes of adults e.g. obese patients.
The 1% rule is useful for assessing smaller areas of burn.
It states that the palmar surface of the patient’s hand, including the digits with the fingers spread apart, is equivalent to 1% of the TBSA.
This is less accurate in patients with a higher BMI.
The Mersey Burns app is a very useful tool for calculating the TBSA (as well as other aspects of burns management).
https://merseyburns.com/
The app allows the area that is burnt to be coloured in on a chart, and will then calculate the TBSA.
Challenges with ascertaining the extent of the burn may also include the fact that some features of the burn may be dynamic.
Blisters may develop, or erythema may improve, changing the proportion of skin that should be included in the TBSA calculation.
Depth of Burn
The severity of the burn, in relation to its depth, is another essential part of the assessment.
Burns can be described as:
- Superficial
- Partial - superficial and deep
- Full
Superficial burns only involve the epidermis.
It is essentially equivalent to sunburn.
Partial burns are divided into superficial partial, which involve the epidermis and the upper layers of the dermis, or superficial deep, which extend into the deeper layers of the dermis.
Deep burns include all layers of the dermis and may include the underlying tissue.
These are classically described as painless (because of the destruction of skin nociceptors) but pain may still be present in nearby tissue that doesn’t have deep burns.
Management
First Aid
Whilst not necessarily the first thing that comes to mind in critical care, this is an essential component of the management of burns.
The priority is cooling of the burn.
This stops further thermal injury occurring, reduces the developing inflammatory response, and can provide symptomatic relief.
This can have benefits up to 2 hours after the initial injury.
Key steps are:
Ideally the water should be clean and cool rather than cold.
Ice should be avoided as it can cause further thermal injury.
Fluid Therapy
This is a key component of burns management, as patients will experience significant fluid shifts due to:
Whilst there will initially be compensation, several hours after the burn insult these losses will start to become significant and lead to increasing compromise.
In general, the patients who will be unable to compensate with oral fluids are:
This can be difficult to assess.
The most common approach is to calculate the fluid requirements.
The most common formula is the Parkland Formula:
Total fluid requirement for 24h after burn = 4ml x weight x %TBSA burn.
Half of this is given over the first 8 hours.
The fluid that should be used is a balanced crystalloid e.g Hartmann’s solution.
Small children e.g. under 30kg, may need larger volumes due to their higher surface area compared to body mass.
Tetanus
It is important to consider tetanus status in patients with significant burns.
Prophylaxis may be required in some cases.
Secondary Infection
Patients will be at increased risk of secondary bacterial infections.
Special care needs to be taken with further hospital care to minimise these risks.
This may include:
Critical Care
All the other tenets of good critical care practice continue to be essential in these patients to avoid complications.
Whilst not necessarily the first thing that comes to mind in critical care, this is an essential component of the management of burns.
The priority is cooling of the burn.
This stops further thermal injury occurring, reduces the developing inflammatory response, and can provide symptomatic relief.
This can have benefits up to 2 hours after the initial injury.
Key steps are:
- Remove any burning material
- Apply cooling
- Cool running water if possible
- Cool compresses if difficult e.g. truncal burns
- Cool for 10-20 minutes minimum
Ideally the water should be clean and cool rather than cold.
Ice should be avoided as it can cause further thermal injury.
Fluid Therapy
This is a key component of burns management, as patients will experience significant fluid shifts due to:
- Loss of skin integrity
- Third space shifts due to inflammatory process
Whilst there will initially be compensation, several hours after the burn insult these losses will start to become significant and lead to increasing compromise.
In general, the patients who will be unable to compensate with oral fluids are:
- Adult patients with TBSA burns > 15%
- Children with TBSA burns > 10%
This can be difficult to assess.
The most common approach is to calculate the fluid requirements.
The most common formula is the Parkland Formula:
Total fluid requirement for 24h after burn = 4ml x weight x %TBSA burn.
Half of this is given over the first 8 hours.
The fluid that should be used is a balanced crystalloid e.g Hartmann’s solution.
Small children e.g. under 30kg, may need larger volumes due to their higher surface area compared to body mass.
Tetanus
It is important to consider tetanus status in patients with significant burns.
Prophylaxis may be required in some cases.
Secondary Infection
Patients will be at increased risk of secondary bacterial infections.
Special care needs to be taken with further hospital care to minimise these risks.
This may include:
- Strict aseptic technique for invasive procedures
- Routine line changes
Critical Care
All the other tenets of good critical care practice continue to be essential in these patients to avoid complications.
Epidemiology
In adults, burns relating to fire are the most common cause.
In children, scalding injuries are more prevalent.
Around 140,000 new burn injuries present to A&E each year in England and Wales.
Risk factors for mortality include:
Overall inpatient mortality for burns is about 14%.
In children, scalding injuries are more prevalent.
Around 140,000 new burn injuries present to A&E each year in England and Wales.
Risk factors for mortality include:
- Increasing age (notably > 50 years)
- Increasing TBSA burn % (notably > 40%)
- Depth of burn
- Delayed resuscitation (> 2 hours post insult)
Overall inpatient mortality for burns is about 14%.
Complications
These are very varied, and can arise from the burn pathology itself or as a complication of subsequent treatment.
- Infection
- Burn site
- Ventilator associated
- Burn site
- Eschars
- Abdominal compartment syndrome
- Tissue oedema - burn related and resuscitative
- Pulmonary oedema and ARDS
- VTE
- Stress ulceration
- Pain - acute and chronic
- AKI
- Psychological
Links & References
- The Resus Room. Burns. 2018. https://theresusroom.co.uk/burns-2/
- Nickson, C. Burns.2016. https://lifeinthefastlane.com/ccc/burns/
- Torres Grau, J. Initial assessment of burn patient. e-LFH. 2016.
- Bishop, S. Maguire, S. Anaesthesia and intensive care for major burns. CEACCP. 2012. https://academic.oup.com/bjaed/article/12/3/118/258510
- Jeevaratnam, J. Estimation of burn extent. e-LFH. 2016.
- Mersey Burns App - https://merseyburns.com/
- Clinical Knowledge Summaries. Burns and scalds. 2017. https://cks.nice.org.uk/burns-and-scalds#!topicsummary
- Cook, S-C. et al (eds). Key clinical topics in critical care. 2014. JP Medical Publishers. London.
