| Management
of Complications |
- It
is important to remember a burned patient is also a trauma patient with
the potential for other injuries beyond those related to the burn.
-
Morbidity
and mortality increases with increased BSA % of burn, in the very young
or very old, and when pre-existing diseases are present such as cardiovascular,
renal or pulmonary disorders.
-
Standard
approach to trauma is followed including assessment for C-spine and head
injuries, pulmonary and abdominal trauma, fractures etc.
|
| Airway and Pulmonary
Complications |
- Carbon Monoxide Poisoning
-
PaO2
may
be elevated with a low oxygen saturation (carbon monoxide preferentially
combines with hemoglobin instead of oxygen)
-
pulse
oximetry cannot distinguish between oxyhemoglobin and carboxyhemoglobin,
resulting in falsely elevated SpO2 reading
-
carbon
monoxide toxicity contributes to the metabolic acidosis by limiting oxygen
transport to tissues
-
carbon
monoxide levels are measured as carboxyhemoglobin
-
Upper Airway Obstruction
Secondary to Edema
-
superheated
air typically causes injury to structures above the vocal cords; lower
respiratory tract is not usually affected
-
airway
burns should be suspected if carboxyhemoglobin is high or burns occurred
in an enclosed space
-
edema
with impaired upper airway patency may not occur for 12 to 18 hrs
-
edema
is progressive during the first 18 to 24 hrs - if airway burn is suspected,
prophylactic intubation should be done early
-
soot
in the nares or mouth, or burned/swollen lips indicate that intubation
is warranted
-
a deep
neck burn may cause external compression of the airway as the skin lacks
the elasticity needed to accommodate tissue edema (compartment syndrome);
escharotomy may be required
-
Chemical Burn to
Upper and Lower Airways
-
water
soluble gases found in smoke from burning plastics or rubber reacts with
water in mucous membranes to produce strong acids and alkalies
-
may
cause bronchospasm, ulceration, edema and damage to ciliary mechanism
-
lipid
soluble compounds are transported to lower airways on carbon particles
and produce cell membrane damage and alveolar flooding
-
pulmonary
infections are common
-
corticosteroids
increase mortality and are contraindicated
-
only
treat infections documented on culture (to reduce chance of developing
infections with resistant organisms)
-
pulmonary
edema may develop as a consequence of profound hyponatremia associated
with burns, excessive fluid resuscitation or renal failure
-
Impaired Chest Wall
Compliance
-
present
with full thickness burns to thorax due to loss of elasticity of skin
-
full
thickness burns to abdomen can impair ventilation due to abdominal compartment
syndrome
-
increased
chest wall resistance from burned skin can lead to laboured breathing and
rapid respiratory deterioration
-
increased
CVP secondary to raised intrathoracic pressures can accelerate the rate
of protein and fluid loss into the burn tissue and increase the chest wall
edema
-
urgent
escharotomy is required on admission, and should extend into fat and possibly
through the fascia
Monitoring
and Management
-
maintain
100% oxygen therapy to enhance oxygen binding with hemoglobin (100% oxygen
decreases the half life of carbon monoxide to 45 minutes)
-
monitor
carboxyhemoglobin and blood gases (the pulmonary lab at SSC measures true
oxygen saturation; calculated values will not be reliable)
-
pulse
oximetry is unreliable - it overestimates oxygen saturation if carbon monoxide
or methemoglobin levels are increased
-
monitor
for metabolic acidosis or lactic acidosis - can develop as a result of
carbon monoxide poisoning or cardiovascular shock
-
assess
for evidence of inhalational injury (suspect if burn occurs in enclosed
space or if carboxyhemoglobin is elevated)
-
soot,
singed airways, stridor, hoarseness or wheeze indicates need for intubation
- AIRWAY EDEMA WILL GET WORSE OVER INITIAL
24 HRS - PROPHYLACTIC INTUBATION IS INDICATED IF EVIDENCE OF AIRWAY BURNS
ARE PRESENT ON ADMISSION!
-
bronchoscopy
may be performed to assess airway for injury
-
be
careful not to cut the endotracheal tube too short
- leave several inches of endotracheal tube beyond the mouth to allow for
facial and lip swelling (which can be extensive!)
-
observe
for neck burns that could further compromise airway
-
monitor
respiratory status for increased RR rate, effort, minute volume and blood
gases - monitor closely for need to mechanically ventilate
-
depolarizing
agents such as succinylcholine are CONTRAINDICATED if neuromuscular blockade
is required for intubation - use non-depolarizing agents such vecuronium
if required (deplolarizing agents may worsen hyperkalemia)
-
increased
effort, peak airway pressures or CVP could indicate compartment syndrome
secondary to thoracic or abdominal burns, hemo/pneumothorax or pulmonary
edema
-
difficulty
with clearance of secretions increases risk for secretion retention; PEEP,
Bronchodilators, frequent suctioning and chest physiotherapy important
-
monitor
for signs of pulmonary infection
|
| Cardiovascular
Complications |
- Burn Shock
-
the
result of massive fluid shifts where intravascular volume is lost into
burned and nonburned tissue
-
increased
vascular permeability, raised tissue osmotic forces and cellular swelling
contribute to the loss of intravascular volume
-
myocardial
depressant factor may contribute to shock by decreasing myocardial contractility
-
Burn Edema
-
during
the first 6 to 8 hours, there is a large loss of protein rich fluid from
the intravascular compartment to the interstitial fluid, due to vascular
permeability
-
intravascular
protein loss results in a loss of the protein gradient between the plasma
and interstitium
-
interstitial
edema fluid forms a gel after approximately 12 hrs and leads to obstruction
of local lymphatics
-
tissue
oxygen tension decreases with edema as distance for oxygen delivery increases
-
the
increased permeability gradually returns to normal by 24 hrs
-
Changes in Nonburned
Tissue
-
fall
in intravascular colloid pressure drives fluid into interstitium
-
vascular
permeability is only minimally affected
-
impairment
of Na/K ATPase leads to a shift of sodium and water from the extracellular
space into the cell
-
ATPase
is normalized by 24 hrs if fluid resuscitation is adequate
-
Hypermetabolic State
-
beginning
at day 5, there is a gradual increase in the metabolic rate to levels ranging
from 2 to 2.5 X normal at day 10
-
characterized
by increased oxygen consumption (cardiac output and minute volume), heat
production, body temperature, hyperglycemia and protein catabolism
-
cardiac
output and CO2 production can double
-
augmented
enteral feedings should be initiated within 48 hrs of the burn injuries
-
inflammatory
mediators generate SIRS (systemic inflammatory response syndrome), increasing
the potential for circulatory failure
Monitoring
and Management
-
Fluid Management
-
monitor
BP, HR and urine output closely (as evidence of adequate fluid resuscitation)
-
monitor
electrolytes, especially potassium and sodium
-
fluid
resuscitation is the cardiovascular priority in burn management
-
the
larger the area of burn, the more significant the fluid deficit
-
the
goal is to achieve a balance between the restoration of adequate tissue
perfusion while minimizing edema formation
-
administer
Lactated Ringers as per the Parkland Formula (one guide for fluid replacement)
- lactated ringers is preferred as it matches extracellular fluid more
closely than normal saline
Caution:
Ringers
Lactate contains potassium; if renal failure develops, ringers lactate
can contribute to hypekalemia
-
4mL/kg/%
BSA of burn - give 50% in first 8 hrs and remaining volume over next 16
hrs (serves only as a guideline and should be modified according to hemodynamic
parameters)
Caution:
trauma victims with other injuries may require higher replacement volumes
-
rapid
boluses are discouraged as they transiently increase pressure and increase
the rate of fluid loss into the burn
-
at
8 to 10 hrs, the rate should be decreased to the lowest level needed to
maintain adequate perfusion
-
colloid
(5% Albumin) may be introduced at 8 to 24 hrs as a drip at the rate of
0.5 cc to 1.0 mL/kg/% BSA burn
-
large
fluid and/or blood products may be required following surgical debridement
Pharmacological Support
-
inadequate
volume resuscitation should be considered as the main cause for hypotension
in the first 3 days, and following debridement of wounds
-
inotropes
may be required if hypotension persists despite fluid replacement
-
beyond
3 days, increasing need for inotropes or vasoconstrictors may indicate
development of septic shock
-
monitor
for signs of infection or sepsis
|
| Renal Complications |
|
| Thermoregulation |
- with
a deep burn, the barrier to evaporative water loss is impaired, promoting
heat loss
-
heat
loss can lead to an increased metabolic rate as the burn victim attempts
to maintain body temperature
-
heat
loss is decreased by covering the wounds and maintaining high room temperatures
|
| Wound Care |
Cleansing
-
keep
wounds covered to minimize infection
-
avoid
prophylactic systemic antibiotics - not useful because wounds are avascular
and antibiotics may promote the growth of resistant organisms
-
topical
antibiotic creams such as Flamazine control bacterial counts and increase
comfort
-
aggressive
wound debridement is essential to the removal of potential sources for
infection such as bacteria and necrotic tissue
-
eschar
(dead tissue) must be removed with scissors and forceps or scalpels; small
areas can be debrided during routine burn dressing changes
-
wet
to dry dressings and scrubbing of wounds during dressing changes can enhance
mechanical debridement
-
enzymatic
debriding agents may be ordered to loosen eschar and promote removal, particularly
in patients unable to go to the OR
-
frequent
surgical debridement is optimal to remove non-viable tissue; bleeding and
fluid loss is generally significant after debridements
-
monitor
all wounds for purulent drainage or signs of infection
Grafts and Dressings
-
polyurethane
film is useful for simple partial thickness burns or donor sites
-
hydrocolloid
dressings may be used on donor sites, but they limit the ability to observe
the site and are not recommended for burned sites
-
deep
partial thickness and very small full thickness burns will heal spontaneously;
should be dressed with bacitracin and adaptic dressing
-
autografts
(from an uninjured area of the patient's own skin or from an identical
twin) provide the only permanent graft material; grafting shortens healing
time and improves the cosmetic appearance of deep partial burns, and is
mandatory for the healing of full thickness burns (decision to graft may
be based on the total % BSA burn and the need to conserve donor sites for
full thickness injuries)
-
in
large area burns, the same graft donor site may need to be used repeatedly
as the only source for graft material; protection of this donor site from
infection is critical
-
when
autograft sites are sparse, donor skin can be minced and placed into a
growth medium to increase the number of epithelial cells or small pieces
of donor skin can be dropped across a large burn (in an attempt to increase
the benefit from a small donor area)
-
cadaver
skin (allograft or homograft) can be used as a temporary dressings
- allografts will promote vascular ingrowth to seal the wound against bacterial
invasion, however, they will be rejected within about 2 weeks
-
xenografts/heterographs
(from other species) such as porcine grafts can also provide temporary
wound dressings - place pigskin dermal side onto the wound (the dermal
side faces the centre of the roll - the graft will roll towards the dermal
side)
-
porcine
grafts should be removed in 3 - 4 days or if purulent discharge is noted
(porcine grafts may be digested by the wound, becoming a source for bacterial
growth)
-
scarlet
red or xeroform dressings are used to protect the donor site; as the site
heals, the edges of the dressing dry and curl - trim the loosened edges
gradually until the entire wound heals (do not forcefully remove donor
dressings or wound healing will be disrupted)
-
tubular
support dressings provide pressure in the range of 10 - 20 mmHg and are
applied 5 - 7 days after grafting to minimize contracture formation
Dressing Routines
-
pain
management is a priority
-
coordinate
physiotherapy with dressing changes
-
splint
limbs to minimize contractures and maintain functional position of joints
|
| GI Function |
|