03 EMSB BURNS 2013 (36)

Question 1

BURN FIRST AID

Answer 1

1. put the fire out
2. remove any still hot clothing, remove any jewellery*
3. COOL THE BURN under cool running water for 20m within the first 3h: do immediately if onscene, after the primary survey if seen subsequently.
4. simultaneously WARM THE PATIENT with warm fluids, environs etc
5. cover with GLADWRAP
6. ELEVATE to reduce swelling
7. no topical creams etc unless >24h from burns unit, and on their advice

* the whole patient is going to swell!

Question 2

WHAT TO DO WITH STUCK CLOTHING IN BURNS PATIENTS

Answer 2

• pull it gently off, any skin that follows was non viable anyway
• if very stuck, cut around

Question 3

EMSB INITIAL BURNS PATIENT MANAGEMENT ALGORITHM

Answer 3

• Patients with burn injuries are initially managed like any other trauma patient, using standard ATLS protocols (Primary survey etc)
• this helps prioritise emergency interventions, eg Intubation, and identify associated traumatic injuries
• certain parts of the process are then specific to the burn patient, eg estimation of burn depth, area and replacement fluids

Question 4

SKIN ANATOMY AND CLASSIFICATION OF BURN DEPTH

Answer 4

• The skin consists of 2 layers, the thin, superficial EPIDERMIS, which constantly sheds, and the thicker, deeper DERMIS, containing the hair follicles, sweat glands, nerves, vessels etc.
• The Dermis rests upon a layer of subcutaneous fat and fascia, allowing the skin to move over the deeper layers.
• Burn depth is no longer categorised anatomically as First/Second/Third degree etc, but rather prognostically according to its ablity to heal: viz
  
  • SUPERFICIAL BURNS: burns where ample epidermal and Dermal cells survive to allow rapid healing by insitu regeneration of the skin, (eg Epidermal burns & Superficial Dermal burns)
  • MID THICKNESS BURNS: burns where sufficient Epidermal (in hair follicles) and Dermal cells survive for spontaneous healing by regeneration, although not rapidly (ie Mid Dermal burns)
  • DEEP BURNS: burns where few (Deep Dermal) or no (Full Thickness) skin cells survive: these burns heal only slowly and with much scarring

Question 5

NAME THE 3 ZONES OF A BURN WOUND

Answer 5

Tissue damage in a burn wound can be divided into 3 zones:

1. A central ZONE OF COAGULATION, where the cells are cooked and dead
2. A (relatively thin) surrounding ZONE OF STASIS, where the cells survive, but are compromised by a damaged micro-circulation. Ongoing cell death in this zone may result in burns extending in area and depth over time.
3. A surrounding ZONE OF HYPERAEMIA, where the tissues are not physically burned, but are hyperaemic due to inflammatory mediators released from the burn. With a large burn (> 20% TBSA), virtually all the unburned skin (and indeed all organ systems) become part of the zone of hyperaemia

Question 6

ESTIMATING BURN DEPTH BY EYE

Answer 6

Burns which are

• Just INTACT ERYTHEMA = EPIDERMAL burns, eg sunburn
• WET & BLISTERED = DERMAL burns (Blisters have a non viable roof separated from a viable base by oedema fluid: with increasing depth of burn the colour of the base deepens from pink to red as it gets closer to the deep dermal vessels, becoming non blanching when full thickness)
• DRY, WHITE & INSENSATE* = FULL THICKNESS, with both Epidermis and Dermis destroyed *

although most full thickness burns will have have partial thickness patches or perimeters which are painful

Question 7

ESTIMATING BURN AREA in ADULTS & CHILDREN

Answer 7

• For ADULTS, the standard WALLACE RULE OF NINES is used, with the palmar area of the hand (including fingers) equating to 1% when summating multiple small burns
• For CHILDREN, with their larger heads and smaller legs, the Rule of Nines is modified thus:
  
  • At 1yr, the Head = 18% (not 9%), and each leg = 13.5% (not 18%)
  • each year, 1% is taken from the head and half added to each leg until adult proportions are attained at age 10.

Question 8

CALCULATING FIRST 24H FLUID REQUIREMENTS FOR ADULT BURNS PATIENTS

Answer 8

• Inflammatory mediators released from burned tissues cause massive oedema formation in the first 24h, both in the burn, and generally.
• For large burns (> 20% TBSA), formal burns fluid replacement is required, using the MODIFIED PARKLAND FORMULA:
  
  • HARTMANS, 3mls/kg/%* burn over 24h, half in the first 8h. (or 10-20L in the first 24h for a big burn)
  • titrate to a U/O of 0.5 ml/kg/h (not more, over-resuscitation exaccerbates oedema)

* counting dermal burns or deeper! NOT intact epidermal burns

Question 9

CALCULATING FIRST 24H FLUID REQUIREMENTS FOR BURNED CHILDREN

Answer 9

• Children have larger surface area to volume ratios, and thinner skin, so they burn more easily.
• They also concentrate urine poorly, and have limited glucose stores, so we
  
  • begin formal burn fluid replacement with the MODIFIED PARKLAND FORMULA earlier, at 10% TBSA (not 20%)
  • add glucose containing maintenance fluids viz: 5%D in NS, at the 4:2:1 rate
  • titrate to a U/O of 1 ml/kg/h, not 0.5

Question 10

BURNS FLUIDS IN THE 2ND 24H

Answer 10

• Oedema formation settles in the 2nd 24H, so fluid replacement changes in volume and composition to:
  
  • 5% ALBUMIN*, 0.5mls/kg/%burn/day (1-2L in a big burn)
  • 4%DNS/5, titrated to U/O of 0.5 ml/kg/h
  • add ORAL fluids as tolerated, and start NE feeding ASAP

* not given on D1 as it just leaks into the tissues, exaccerbating oedema

Question 11

IV ACCESS OPTIONS IN BURNS PATIENTS

Answer 11

• Peripheral lines, central lines and IOs placed through intact or burned skin are all options.
• peripheral IVs (and Art lines) placed in burned skin should be sutured
• in many big burns, the groin creases will be spared, facilitating groin line placement

Question 12

NGTs in BURNS PATIENTS

Answer 12

the combination of

• their propensity for ileus
• the benefits of early NE feeding (better nutrition, less sepsis from GI bacterial translocation)

means NGT are indicated for all large burns, ie > 20% TBSA in adults > 10% TBSA in children

Question 13

IDCs IN BURNS PATIENTS

Answer 13

• As hourly urine output is the key indicator of adequate fluid resuscitation in burns patients, IDCs are indicated for all large burns, ie
• > 20% TBSA in adults
• > 10% TBSA in children

Question 14

PERINEAL BURNS

Answer 14

• should be catheterised early, before they swell

Question 15

HAEMOGLOBINURIA AND MYOGLOBINURIA

Answer 15

Release of Haemoglobin and Myoglobin from injured tissues, may result in their renal excretion, with

• brownish-red urine
• renal tubular blockage and ARF

TREATMENT

• address cause if able, eg COMPARTMENT SYNDROME
• double U/O to 1-2 ml/kg/h with IVT +/- MANNITOL
• urinary alkalinisation with BICARB is no longer recommended, based upon the evidence

Question 16

WHAT’S THE DIFFERENCE BETWEEN ESCHAROTOMY AND FASCIOTOMY?

Answer 16

• ESCHAROTOMY = incision of a rigid burn eschar down to subcutaneous fat to relieve pressure which is causing limb ischaemia or resp compromise. Its a relatively superficial procedure, and is generally painless, only requiring LA for the viable ends of the incisions
• FASCIOTOMY = incision dividing the fascia over a tight muscle compartment. It is a deeper incision, normally requiring GA

Question 17

ESCHAROTOMY : HOW?

Answer 17

• can be done bedside in emergency but best taken to theatre for full surgical prep etc
• mark lines of incision, generally along the A-P junctions of the limbs*, and an H centered on the costal margins, and with with verticals along the AAL, for the trunk, continuing few mm onto normal skin
• anaesthesia is not reqd, just LA for the viable ends
• incise down to fat with scalpel or diathermy, look for visible separation
• expect a lot of bleeding: control with local measures (diathermy, ties, stats), NOT pressure bandages

* just do one side of the finger

Question 18

2 NERVES NOT TO CUT WHEN DOING ESCHAROTOMY

Answer 18

Do not cut:

1. the ULNAR NERVE at the elbow
2. the LATERAL POPLITEAL NERVE over the fibular head

skirt around!

Question 19

THE 4 ‘P’s of COMPARTMENT SYNDROME

Answer 19

the 4 Ps are:

1. PAIN*
2. PARAESTHESIA
3. PARALYSIS
4. PULSE LOSS & POOR PERIPHERAL PERFUSION

* PERSISTENT PAIN in an at risk limb is the principle red flag, pulse loss is a late sign, and even ‘normal’ compartment pressures (<10mmHg) do NOT reliably rule out CS

Question 20

A LIMB WITH COMPARTMENT SYNDROME IS….

Answer 20

ROCK HARD

Question 21

TUBES NEEDED FOR SERIOUS BURNS

Answer 21

1. IVT, probably CVC & Art
2. NGT
3. IDC
4. +/- ETT

Question 22

ICE WATER IRRIGATION FOR BURNS

Answer 22

Whilst COOL WATER irrigation is an excellent first aid treatment that reduces pain and burn extension, ICED WATER should not be used as it

• exaccerbates hypothermia
• may cause vasoconstriction or cold injury which extends the burn

Question 23

INHALATION INJURY IN BURNS PATIENTS

Answer 23

• Inhalation injury should be suspected in burns patients with a history of entrapment, and with evidence of facial burns, especially involving steam (which carries more heat).
• Inhalation of hot gases may cause
  
  • airway burns
  • pulmonary burns
  • systemic toxicity due to CO, Cyanide etc
• all are indications for early Intubation and ventilation with 100% O2

Question 24

CARBON MONOXIDE POISONING

Answer 24

• CO is a colourless, odourless gas produced by the incomplete combustion of carbon.
• It binds very strongly to Hb, with a dissociation half life of 250 minutes in room air, reducing the oxygen carrying capacity of the blood.
• Detection of this deficit is, however, difficult because:
  
  • CO-Hb gives the skin a deceptively pink colour
  • Regular Pulse Oximeters cannot detect it, special CO-OXIMETERS are required, but levels of up to 15% are normal in smokers, and asymptomatic
  • Arterial gas analysis measures the pO2, not saturation, which may remain normal in CO poisoning
  • a significant part of the toxicity of CO occurs inside the cell, due to disruption of INTRACELLULAR CYTOCHROMES, irrespective of O2 delivery

TREATMENT

• assume all confused burns patients have CO poisoning
• give O2 at 15 LPM to enhance washout
• consider ETT and 100% O2, esp if resp burns suspected
• HYPERBARIC O2 is usually logistically too difficult and benefit debatable

Question 25

HOW TO LIMIT AIRWAY SWELLING IN BURNS PATIENTS WHERE INTUBATION IS UNDESIRABLE

Answer 25

1. sit them up ++ and
2. restrict fluids to 100mls/h, not PARKLAND

Question 26

INDICATIONS FOR TRANSFER OF BURNS PATIENTS

Answer 26

Ideally, all significant burns should be reviewed at a burns unit, especially those which are:

• Large : >10% TBSA in adults or 5% in children
• Deep : >5% full thickness
• involving a specialised area, eg face, hands, feet, perineum
• in the very young, very old or pregnant
• complicated by significant other injuries or medical conditions
• electrical or chemical burns
• associated with inhalation injury

Question 27

SHOULD BLISTERS BE DE-ROOFED?

Answer 27

• As a general rule, NO
• doing so may allow the base to dry out and deepen

Question 28

TETANUS PROPHYLAXIS

Answer 28

• to be fully immunised against Tetanus, a person needs to have had
  
  • a full course of 3 immunisations (ADT etc)
  • 10 yearly boosters
• so whenever a patient with an injury or burn is seen:
  
  • verify fully immunised and if not, give any catchup doses
  • give a booster ADT if > 10y since the last, or > 5y for major wounds
  • add TETANUS IMMUNOGLOBULIN (TIG) 250 U IMI if a MAJOR WOUND and not fully immunised

Question 29

PATHOPHYSIOLOGY OF ELECTRICAL INJURIES

Answer 29

Electrical Injuries can be divided into low voltage, high voltage, and lightning injuries

• LOW VOLTAGE INJURIES are caused by contact with less than 1000V, usually domestic 240V or 415V. These voltages cause only modest current flows, with small cutaneous burns at the current entry and exit sites, no deep burns, and no cardiac injury (although arrhythmia can cause immediate cardiac arrest).
• HIGH VOLTAGE INJURIES are caused by contact with >1000V, typically 11,000V or 33,000V. These voltages cause major cutaneous burns due to current flow or flash, and deep burns involving the myocardium and muscle compartments
• LIGHTNING STRIKES involve very high voltages, but for very short durations. Serious cutaneous burns are common, but deep burns rare. Unlike other electrical injuries, immediate death from Lightning strikes is often caused by resp centre depression, not arrhythmia, and may respond to immediate EAR.

Question 30

GENERAL MANAGEMENT PROTOCOL FOR ELECTRICAL INJURIES

Answer 30

• Patients with Electrical injuries are initially managed using the ATLS protocols (with Primary Survey etc), the same as any other trauma patient
• This helps prioritise immediate needs and identifies associated traumatic injuries, eg due to muscle spasm, fall, etc
• Specific thought is then given to the possibility of deeper burns, involving the Myocardium or muscle compartments

Question 31

WHEN TO MONITOR FOR ONGOING ARRHYTHMIAS IN ELECTRICAL INJURY

Answer 31

whilst an ECG on arrival is an ATLS requirement for any trauma patient, including those with electrical injury, ongoing monitoring is only required for those at risk of myocardial injury, ie those with:

• high voltage injury
• evidence of myocardial injury:
  
  • LOC at the scene
  • Arrhythmia/ST changes on ECG
• pre-existing myocardial disease

Question 32

CHEMICAL BURNS

Answer 32

• Chemical burns differ from thermal burns in that, whilst the onset of tissue damage is slow, it continues to progress until the agent is neutralised. Hence, initial first aid for chemical burns is to remove contaminated clothing and IRRIGATE WITH WATER FOR AT LEAST 30m*.
• In addition, chemical burns casualties may have systemic toxicity from absorption or inhalation of the agent as well.
• The commonest Domestic chemical burns are ALKALI BURNS due to bleaches and cleaners. Alkalis cause a LIQUEFACTIVE NECROSIS which penetrates deeply
• in contrast, ACID BURNS cause a COAGULATIVE NECROSIS

* make sure the irrigant water ‘falls to the floor’ rather than pools under the patient

Question 33

WHITE PHOSPHORUS BURNS

Answer 33

• White Phosphorus may be encountered in military settings.
• it ignites spontaneously on contact with air, but can be doused with water
• Following dousing, it may be neutralised with dilute COPPER SULPHATE wash, but this itself should then be washed off

Question 34

SIZING OF ETT FOR BURNS PATIENTS?

Answer 34

• Bigger is better, to facilitate later bronchoscopy, suction etc

Question 35

ARE INTACT EPIDERMAL BURNS COUNTED WHEN USING THE PARKLAND FORMULA?

Answer 35

• No: count only Dermal burns (broken skin) and deeper

Question 36

ARE ESCHAROTOMIES NEEDED FOR DERMAL BURNS?

Answer 36

• No : they are for the RIGID ESCHAR of a full thickness burn only