The Initial Surgical Management of the Critically Ill Burn Patient



Fig. 10.1
Early management algorithm



Frameworks of trauma such as Advancement Trauma Life Support (ATLS) or Emergency Management of Severe Burns (EMSB) provide the burns professional with treatment priority principles that emphasise the fact that timely resuscitation, assessment and recognition of life threatening injuries, together with early transfer to a definitive burns unit saves lives.

The recognised classic treatment algorithm of primary survey with the ABCDE (Airway, Breathing, Circulation, Disability and Environment/Hypothermia protection) approach, tip-to-toe secondary survey and continuous reassessment with definitive transfer to and expert facility displays a number of variations in the management of burn patients.

The potential for an impending airway compromise in major burns with an inhalational injury will require the early involvement of the Anaesthesia/Intensive Care teams in order to secure a definitive airway in the form of an endotracheal tube. Airway assessment and the possibility of an inhalational injury, especially if the injury has occurred in an enclosed space, need to be coupled with the careful assessment for potential injury of the cervical spine.

Potential inability or delay in weaning off burns patients from mechanical ventilation may require the insertion of a tracheostomy either through a percutaneous or open surgical method. Both methods are safe in expert hands with the choice of method depending on the state of the soft tissues of the neck affected by the burn, experience of the operator and the size of the burn and the body habitus of the patient. Tracheostomy is therefore a fundamental skill for both the burn surgeon and the intensive care specialist [10].

The adequacy of the oxygenation and ventilation may be compromised by the presence of full thickness burns of the chest wall and abdomen leading to decreased compliance and high inflation pressures (Fig. 10.2).

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Fig. 10.2
Full thickness burn to the chest wall

The full thickness skin eschar acts as a ventilation compliance-limiting factor. The presence of ventilation difficulties should prompt urgent assessment of the need for releasing escharotomy incisions performed under suitable theatre conditions and by professionals with adequate experience. Escharotomies will immediately improve ventilation and avert the possibility of abdominal compartment pressure [11, 12].

Escharotomies in the chest and abdomen are performed from unburned skin to unburned skin and along the anterior axillary lines and across the lower edge of the rib cage transversely. Occasionally there is a need to join these lines to provide a more definitive release that is ensured by direct visualisation of healthy bulging fat through the escharotomy incisions [13].

The adequacy of the circulation in the burns patient requires prompt insertion of Intravenous access in the form of two large cannulas preferably through unburned skin in order to promptly avert the hypovolemia that occurs as a consequence of the burns distributive shock.

In the case of full thickness circumferential burns to the limbs, the need for escharotomies in order to ensure adequate distal blood flow to the extremities is an urgent priority [14].

Upper limb escharotomies (Fig. 10.3) are performed along the lateral and medial axial lines with the arm in pronation applying the principles described above. Great care must be exerted to avoid damage to relevant neurovascular structures, especially around the medial epicondyle area, where the ulnar nerve is at great risk. When electrical injury is the cause of the soft tissue damage, the presence of muscle necrosis due to compartment syndrome may require the combination of escharotomies with fasciotomies in order to provide limb salvage and function preservation.

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Fig. 10.3
Upper limb escharotomy

Lower limb escharotomies are performed also along lateral and medial axial lines down to healthy bulging fat avoiding damage to the common peroneal nerve at the level of the fibular neck laterally and proximally, and to the posterior tibial neurovascular bundle and the great saphenous vein distally.

Disability and neurological assessment of the critically ill major burned patient can be problematic and difficult to ascertain due to the fact that the patient may have been intubated onsite, In this case, obtaining a good burns and trauma history and performing a thorough physical examination will help to develop a high degree of suspicion and to exclude the possibility of a brain or spinal injury. Any lack of normalisation of neurological function following decrease of sedation and analgesia or a failed extubation should alert the burns professional about the possibility of neurological damage.

From the environmental point of view, hypothermia is often an overlooked risk factor in the management of the major burn, the importance of which cannot be overstated. Continuous reassessment is fundamental whilst resuscitating the patient in order to prevent the early onset of the lethal triad of hypothermia, acidosis and coagulopathy in burns, which is associated with significant mortality [15].

The importance of these complications cannot be underestimated taking into consideration the established practice of early excision of the burn wound that may involve severe blood loss potentially increased by a deranged clotting cascade and lack of platelet adhesion accentuated by hypothermia.

Keeping the patient warm at pre-hospital level and during transfer can therefore avert the delay in acute surgical debridement due to hypothermia. Temperature control can be achieved by the use of radiant heaters in the Emergency Department, and by keeping these patients in a warm room whilst in the burns unit. The infusion of warm intravenous fluids via new generation intravascular warming catheters and forced hot air technologies, such as such as the Bair HuggerTM, are methods commonly used to avoid hypothermia [16].

Hypothermia can decrease the ability of the burn patient to withstand the stress of surgery and become less tolerant to the effect of anaesthetic drugs [17].

Adequate assessment of the burn wound in size and depth are performed in order to provide priorities of treatment.

Burns surgery is ultimately aimed at preserving the blood supply of the skin and all of the skin functions which include protection from environmental elements and pathological organisms, immunological surveillance, fluid and electrolyte homeostasis, maintenance of protein and electrolyte concentrations, thermoregulation and control of heat loss.



10.2.3 Assessment of the Burn Wound


The assessment of the size of the burn wound can be performed by clinical methods or chart-based methods, but in the acute situation it is frequent to use a combination of both depending on the resources available and the experience of the clinician.

The Wallace rule of nines [18], serial halving [19], modified Lund and Browder charts [20, 21] and the use of the palm of the patient’s hand as a percentage calculator [22] are recognised methods for calculation of the burned total body surface area. These methods provide an estimation of the total body surface area, but the burn injury can be over calculated in the case of small burns and under assessed in larger injuries. These inaccuracies can have a direct effect on the resuscitation regime applied and can result in serious under or over resuscitation [23].

Clinical experience provides a theoretical advantage in the assessment of total body surface area, but it is not infallible. A recent review proved the difficulties of burn area accuracy assessment in trauma situations by experienced teams not only in civil situations but also in military environment [24].

Modern technologies are likely to overcome the relative subjectivity of some of these assessment methods. The increased accuracy of software and mobile technology has already started to produce interesting diagnostic tools that supplement clinical judgement [25, 26].

In terms of depth, burn injuries are classified according to the damage to the epidermal and dermal layers of the skin layers of the skin.

Burns are dynamic injuries characterised by three distinct areas of thermal damage: a central area of non-salvageable necrosis, a potentially salvageable area of stasis characterised by the outpouring of inflammatory mediators and by its responsiveness to early resuscitation and early debridement and an area of surrounding inflammation and vasodilatation [27].

The clinical parameters that define the classification of burn injuries in terms of depth are the colour, capillary refill, sensation, presence of blisters and potential for self-healing.

Burns can then be classified into superficial or epidermal burns, dermal or partial thickness burns and full thickness burns (Figs. 10.4, 10.5, 10.6 and 10.7).

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Fig. 10.4
Superficial partial thickness burns


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Fig. 10.5
Mid-dermal partial thickness burn


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Fig. 10.6
Deep dermal partial thickness burn


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Fig. 10.7
Full thickness burn

Partial thickness burns can then be subdivided into superficial partial thickness or superficial dermal, mid-dermal partial thickness burns and deep dermal partial thickness.

This classification illustrates the progressive damage to epidermis, papillary dermis, reticular dermis and ultimately the full thickness of the skin down to the subcutaneous tissue.

It is easy to understand that as the intensity of the thermal injury increases, the damage in terms of depth will also increase.

The colour will change from a vivid pale pink with brisk capillary refill in superficial injuries to a cherry red colour in deep dermal injuries and a leathery brown-yellow presentation in full thickness wounds.

The presence of blisters represents the pathognomonic physical sign of the partial thickness burn and the actual potential skin loss that needs to be accounted into any burns area assessment. Blisters will become larger and coalesce as the burn deepens. Wounds will have a moist appearance in superficial injuries and a dry appearance in deep damage.

As the blood supply decreases when the wound deepens, the damage to the sensory supply of the skin will also increase. A superficial wound will be intensely painful compared to the insensate presentation of a deep injury.

The clinical translation of a superficial injury compared with one of a deeper pattern relates to the potential need for surgical management.

A superficial partial thickness injury may require resuscitation if it is extensive, but it is likely to heal without any excisional surgery over a period of 3 weeks without developing abnormal scarring.

Any burn injury unlikely to follow a spontaneous resolution pattern within a 3-week period is likely to require surgery in order to avoid delayed healing with associated unwanted sequelae [28].

Current advances in the assessment of the depth of the burn include the use of modern imaging technologies such as Laser Doppler flowmetry.

This technique is most useful in aiding to support the burns clinician in his decision to operate or not in indeterminate- or mixed-depth burns, especially in children.

Laser Doppler imaging (LDI) is a noninvasive technique for predicting burn wound outcome based on measurement of cutaneous blood flow, measured in perfusion units (PU) and assessed by the power spectrum of Doppler frequency shift on reflected laser light [29].

Laser Doppler readings in deep burns correlate well with the need for grafting and the development at a later stage of abnormal scarring [29, 30].


10.2.4 Fluid Resuscitation


Accurate total body surface area assessment is fundamental to decide on a judicious regime of fluid resuscitation.

The Parkland formula [31] provides a common language of fluid resuscitation between burns professionals and adequate resuscitation from burn shock.

The formula: 4 ml of Hartmann’s solution × body weight (kg) × % total body surface area provides a 24 h fluid calculation that it is administered in two distinct periods and amounts, the first half within the first 8 h of the burn injury and the second half is administered for 16 h following the first period. This split regime of resuscitation aims to overcome the phenomenon of third spacing and fluid creep that occurs during the first 24 h of fluid resuscitation and the early onset of burn oedema.

There are some variations in fluid resuscitation affecting paediatric patients. In these cases, and in addition to the resuscitation with Crystalloid, 5 % Dextrose in 0.45 % Normal Saline is given as maintenance in order to address the hypoglycaemia caused by quick depletion of glycogen deposits in children. This is administered according to body weight, with 100 cc/kg given for the first 10 kg of weight, 50 cc/kg for the next 10 kg and 20 cc/kg for any kg between 20 and 30 kg of weight.

The distributive and hypovolemic components of burn shock, that are characterised by intravascular volume depletion, low pulmonary artery occlusion pressures, elevated systemic vascular resistance and depressed cardiac output [32, 33], are averted by the early administration of intravenous fluids that constitute the most important single intervention in the care of the burn patient [34].

Monitoring of resuscitation is essential to warrant organ perfusion and positive outcomes.

Urine output of at least 0.5 cc/kg/h in adults and 1 cc/kg/h in children and resolution of any potential acidosis and/or raised markers of hypo perfusion are commonly used targets.

Factors that influence resuscitation include burn depth, Inhalational injury, associated injuries, age, delayed resuscitation, need for escharotomies, and associated alcohol and drugs intake.

Under resuscitation can lead to renal failure and inadequate tissue perfusion. Fluid overload can also lead to severe complications including compartment syndrome, intraocular hypertension, pulmonary overload and massive oedema [35].


10.2.5 Referral to a Burns Unit


Following application of the principles outlined above, to assess and resuscitate burn injuries the patient needs, once stabilised, to be safely transferred to an area of expertise for the ultimate management of the burn wounds.

The British Burns Association suggests the following minimum threshold for referral into specialised burn care services [36]:



  • All burns ≥2 % TBSA in children or ≥3 % in adults.


  • All full thickness burns.


  • All circumferential burns.


  • Any burn not healed in 2 weeks.


  • Any burn with suspicion of non-accidental injury should be referred to a Burn Unit/Centre for expert assessment within 24 h.

May 4, 2017 | Posted by in CRITICAL CARE | Comments Off on The Initial Surgical Management of the Critically Ill Burn Patient

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