Editing Burns (section)

== '''Initial assessment, resus and treatment of burns patients''' ==

=== '''Pre-hospital''' ===

** Suspect inhalation injury, and give 100% oxygen if required
** Remove all jewellery
** 20 minutes of cool running water is beneficial within 3 hours of injury, but don't cool the wound, as it can lead to hypothermia
** Transport to emergency
** Dry dressings or clean sheet to avoid maceration
** Warm with blankets
** Don't use IM or S/C analgaesia - impaired absorption from vasoconstriction

=== '''Initial treatment of burn''' ===

** Remove clothing and debris (don't peel off adherent clothing)
** Cooling
*** Cool/room temp water
*** Alternatively cover with wet gauze
*** Avoid ice or very cold water
*** Avoid macerating wound - max five minutes
** Simple cleansing
*** Gently clean with gauze and normal saline, or 0.1% aqueous chlorhexidine
*** Remove loose skin/debris
*** A clean flannel can be substituted if gauze is unavailable
*** Shave burns to a 2cm border at initial cleaning, and with subsequent dressing changes
** Debride
*** Remove sloughed or necrotic skin, ruptured blisters
*** Management of intact blisters is controversial. Indications for debriding them:
**** Thick-walled blisters
**** Blisters over joints or dependent areas
**** >2cm in diameter
** Appropriate dressing
*** Superficial and superficial partial thickness do not need chemoprophylaxis - use moisturiser cream
*** Deep partial or full thickness should have a topical antibiotic
*** Do not use systemic antibiotics prophylactically 
*** No role for topical steroids
*** If transferring, dry gauze is appropriate
*** For longer-term dressings, use gauze with a non-stick layer or hydrocolloid eg duoderm
** Pain management
*** Simple stuff
*** Elevation may help
*** Itching - use antihistamines
** Tetanus prophylaxis

=== '''Moderate to severe burns: initial assessment and treatment''' ===

** '''Trauma ABCD assessment'''
*** Can be hard to take BP due to charred extremities - need invasive arterial monitoring in this setting, with peripheral pulses being used as a proxy of perfusion in the meantime
** '''Basics'''
*** Cover burns with clingfilm (can give a rinse if possible)
*** Bloods (?G+H)
*** IV access - prefer peripheral veins in unburned skin, but IVC through burned skin is better than no access at all
*** BSL
*** Pregnancy test
*** Check for compartment syndrome
**** Especially high-voltage electrical injuries, circumferential burns, delayed resus, or high-volume resus
**** Typically evolves over 12-72 hours following burn and resus
**** Hands, feet, legs, forearms, abdomen, eyes
**** Check for acute nerve compression syndromes
**** Serum CK and myoglobin can assist diagnosis
*** Remove jewellery
*** NGT if vomiting or TBSA>20%, according to Sabiston, as high-risk for aspiration
*** Tetanus if >10% TBSA
*** Consider deliberate burns
**** Burns on soles of feet
**** Buttocks
**** Other injuries present
**** Poor nutritional/developmental/psychologic state
** '''Assess for inhalation injury'''
*** Generally occurs above vocal cords
*** Can be catastrophic
*** Tends to worsen over the course of hours, not minutes
*** '''Signs of inhalation injury:''' (all individually non-sensitive, need to use clinical context as a whole, and bronchoscopy)

**** Persistent cough, stridor, wheezing
**** Hoarseness - impending airway obstruction
**** Deep facial or circumferential neck burns
**** Singed nares/inflammation
**** Carbonaceous sputum
**** Obvious blistering/oedema of oropharynx
**** Elevated carbon monoxide or cyanide levels
**** Hypoxia/hypercapnia

*** AIS grading of inhalation injury by bronchoscopy is as follows:

**** 0 (no injury) – Absence of carbonaceous deposits, erythema, edema, bronchorrhea, or obstruction
**** 1 (mild injury) – Minor or patchy areas of erythema or carbonaceous deposits in the proximal or distal bronchi
**** 2 (moderate injury) – Moderate degree of erythema, carbonaceous deposits, bronchorrhea, or bronchial obstruction
**** 3 (severe injury) – Severe inflammation with friability, copious carbonaceous deposits, bronchorrhea, or obstruction
**** 4 (massive injury) – Evidence of mucosal sloughing, necrosis, endoluminal obliteration

*** Cyanide inhalation

**** Cyanide toxicity can occur with burns in enclosed spaces - anaerobic metabolism -> hyperlactataemia or unexplained metabolic acidosis. 
**** Treat with hydroxycobalamin.

*** Carbon monoxide exposure

**** Presume in all suspected inhalation injuries
**** Most commonly causes dizziness, altered mental status, arrhythmias or even MI
**** HbCO levels:
***** <20% asymptomatic
***** 20-30% headache/nausea
***** 30-40% dyspnoea, confusion
***** 40-60% syncope, seizures, obtundation
***** >60% death
***** Also look for cherry-red skin but this is rare
***** If exposure has occurred, give 100% O2 via non-rebreather. Half-life is expected to be 40 mins with this, or 4 hours without O2.

*** '''Intubate if:'''

**** Deep burns to face and neck 
**** Blisters/oedema of oropharyns, burns inside mouth
**** Stridor (late)
**** Use of accessories
**** Resp distress or signs of compromise (fatigue, inability to clear secretions)
**** Sub/suprasternal retractions
**** Hypoventilation 
**** TBSA >40% - often intubated prophylactically for impending oedema
**** Needing emergent transfer
**** Carboxyhaemoglobin >10% is a relative indication
**** May require bronchoscopy later - prefer size 8mm internal diameter tube (4.5mm in child)

*** If not intubated:

**** Aim sats >90% with humidified high-flow
**** Coughing/deep breathing q2h
**** Chest physio
**** Saline nebs
**** Bronchodilator if wheezing
**** Mobilise if possible
**** Prophylactic antibiotics are not needed for inhalation injury

=== '''Fluid resuscitation''' ===

*** Burn shock - rapid fluid shifts leading to decreased intravascular volume
*** Therefore aggressive and early resuscitation is necessary
*** Use CSL for all >2yo. Use CSL with 5% dextrose for <2yo.
*** Recommended formal fluid resus if TBSA >15%
*** Hourly UO should be maintained at 0.5ml/kg/hr
*** Be aware that over-resus may worsen airway oedema
*** 2-4xTBSA % per kg for second/third degree burns

**** Half in first 8 hours, half during subsequent 16
**** Under-resus leads to hypoperfusion and end-organ injury. Over-resus leads to oedema (burn depth progression, compartment syndrome, airway oedema).
**** Initial rate given by TBSA x10, plus 100mL/hr for every additional 10kg of weight above 80kg. Continue this rate until a formal calculation has been done. 

*** Generally start introducing colloids after 24 hours

=== '''Escharotomies''' ===

** Required when compromised circulation may be present due to the combination of unyielding eschar and generalised oedema (initially venous, then arterial)
*** Assess as for compartment syndrome
*** Generally don't do prophylactic escharotomy at a peripheral site if transfer is planned same day, because the problem usually arises after 12 hours of resuscitation causing third-spacing
*** Required more often with circumferential burns, but can be needed with non-circumferential too
** Can also occur on trunk, with restriction of ventilation
** Perform at bedside or OT by incising the lateral and medial aspects of the extremity, completely through the eschar, with a scalpel or diathermy. Must incise the entire constricting eschar longitudinally.
*** Stop once healthy fat is seen and the tissue springs about 1cm apart - don't need to go down to fascia
** For upper limb, carry incision down onto thenar/hypothenar eminences, and sometimes even fingers. 
** Reperfusion injury can occur afterwards
**

=== '''Principles of dressings:''' ===

* Protect the damaged epithelium
* Minimise bacterial and fungal colonisation
* Provide splinting action to preserve function, as needed
* Should be occlusive to reduce evaporative heat loss and minimise cold stress
* Should provide comfort over the painful wound


'''Superficial'''

* Usually need an absorptive dressing for first 72 hours
*

'''Superficial partial thickness:'''

* Cover with either
** Daily dressings with topical antibiotics, gauze, tubigrip OR
** Longer-lasting silver dressings (ActiCoat)
*** More useful in contamination, clinical infection, deeper burns, or burns with large surface area
* Wounds expected to take >3 weeks for re-epithelialisation would benefit from surgical excision and grafting
* Partial thickness scald burns, especially in children, generally can have a trial of conservative management, although they should be reviewed at 24 hours in case of worsening. Gentle debridement of dead skin in bath, solugel or paraffin on top maybe, and good oral analgaesia.
*

'''Deep partial thickness/full thickness:'''

* "There is no advantage to unexcised eschar"
* Will need prompt surgical excision and wound closure, usually with autograft
* Depth of excision is below the dermis. Absence of bleeding identifies necrotic subcutis.
* True invasive burn wound infection with bacteria or mould may require amputation/wide debridement
* Initial dressing is aimed at holding bacterial proliferation in check, and completely occluding until the operation is performed