Thermal and Inhalation Thermal and Inhalation InjuryInjury
Chapter 39Chapter 39Written by : Melissa Dearing – LSC-KingwoodWritten by : Melissa Dearing – LSC-Kingwood
EpidemiologyEpidemiology
In the U.S.In the U.S. Results in 60,000 hospitalizations Results in 60,000 hospitalizations
annuallyannually 6000 deaths annually6000 deaths annually Mortality the highest inMortality the highest in
Young childrenYoung children elderlyelderly
EpidemiologyEpidemiology
In pediatric thermal injuries:In pediatric thermal injuries:Less than 5% are the result of Less than 5% are the result of
chemical or electrical burnschemical or electrical burns
10-15% result from flame burns10-15% result from flame burns When associated with smoke When associated with smoke
inhalation are the most deadlyinhalation are the most deadly
Scalding burns account for 75-Scalding burns account for 75-
80%80%
PreventionPrevention
Smoke detectors that workSmoke detectors that work
Keep matches out of reachKeep matches out of reach
Lower the temp on hot water heatersLower the temp on hot water heaters
Cover electrical outletsCover electrical outlets
Buy flame resistant children’s Buy flame resistant children’s
clothingclothing
Use fire-safe cigarettesUse fire-safe cigarettes
Mortality RateMortality Rate
Highest when:Highest when:
Burn exceeds 30% body surface Burn exceeds 30% body surface
area.area.
See figure 39-1See figure 39-1
Associated with smoke inhalationAssociated with smoke inhalation
Child younger than 4 years oldChild younger than 4 years old
PathophysiologyPathophysiology
Disruption of the protection Disruption of the protection provided by skin:provided by skin:
Protects body from infection and injuryProtects body from infection and injury Prevents fluid lossPrevents fluid loss Regulates body tempRegulates body temp Provides sensory input from Provides sensory input from
environmentenvironment
PathophysiologyPathophysiology
Composed of 2 layersComposed of 2 layers Epidermis – thin outer layerEpidermis – thin outer layer Dermis – deeper, thick inner layerDermis – deeper, thick inner layer
Dermis contains:Dermis contains: Hair folliclesHair follicles Sweat glandsSweat glands Sebaceous glandsSebaceous glands Sensory fibers for touch, pain, pressure and Sensory fibers for touch, pain, pressure and
temptemp Beneath the dermisBeneath the dermis
Subcutaneous tissue composed of Subcutaneous tissue composed of connective tissue and fatconnective tissue and fat
Classification of BurnClassification of Burn
11stst Degree Degree Superficial Superficial Involves only the dermisInvolves only the dermis Skin is redSkin is red No blistersNo blisters Painful and sensitive to touchPainful and sensitive to touch
Classification of BurnClassification of Burn
22ndnd Degree Degree Involve the epidermis and part of Involve the epidermis and part of
the dermisthe dermis Very painful due to nerve endings Very painful due to nerve endings
that survive the insultthat survive the insult Blistering is commonBlistering is common Healing occurs quicklyHealing occurs quickly
Classification of BurnClassification of Burn
33rdrd Degree Degree ““Full thickness” burnsFull thickness” burns Involve injury and necrosis below Involve injury and necrosis below
the hair follicles thru the entire the hair follicles thru the entire thickness of skin and into thickness of skin and into subcutaneous tissuesubcutaneous tissue
Area swells slowly and appears Area swells slowly and appears blanchedblanched
Sensory nerves are destroyed Sensory nerves are destroyed causing local anesthesiacausing local anesthesia
ManagementManagement
11stst degree usually heals by itself degree usually heals by itself 22ndnd and 3 and 3rdrd degree may require degree may require
grafting, excision and grafting, excision and antimicrobial therapy such as antimicrobial therapy such as Silva dineSilva dine
ManagementManagement
Important to initiate accurate Important to initiate accurate fluid resuscitation ASAPfluid resuscitation ASAP Careful: overaggressive fluid Careful: overaggressive fluid
resuscitation may result in high resuscitation may result in high extravascular hydrostatic pressure, extravascular hydrostatic pressure, pulmonary edema and soft tissue pulmonary edema and soft tissue swellingswelling
Urine output is a good indicator Urine output is a good indicator of hydrationof hydration
Inhalation InjuryInhalation Injury
Mortality from smoke injury Mortality from smoke injury alone is 0-11%alone is 0-11%
Mortality from smoke injury and Mortality from smoke injury and burns is 30-90%burns is 30-90%
Smoke inhalation that results in Smoke inhalation that results in pneumonia has a mortality rate pneumonia has a mortality rate of 60%of 60%
Physiologic Consequences Physiologic Consequences of Inhalation Injuryof Inhalation Injury
Box 39-1Box 39-1
Upper Airway InjuryUpper Airway Injury
Results in obstruction from:Results in obstruction from: EdemaEdema HemorrhageHemorrhage Ulceration of mucosaUlceration of mucosa
Mild pharyngeal edema can lead Mild pharyngeal edema can lead to complete upper airway to complete upper airway obstruction and asphyxia in only a obstruction and asphyxia in only a few hoursfew hours
Inflammation can be the result of Inflammation can be the result of ammonia, hydrogen chloride and ammonia, hydrogen chloride and chemical irritants found in smokechemical irritants found in smoke
Lung Parenchyma InjuryLung Parenchyma Injury
Only steam is capable of Only steam is capable of overwhelming the upper airway overwhelming the upper airway defenses and transmitting heat defenses and transmitting heat to the subglottic airwaysto the subglottic airways
Direct cellular injury results in Direct cellular injury results in inflammatory responseinflammatory response Leads to bronchoconstrictionLeads to bronchoconstriction Increase in tracheobronchial blood Increase in tracheobronchial blood
flow with edemaflow with edema Leukocyte infiltrationLeukocyte infiltration
Lung Parenchyma InjuryLung Parenchyma Injury
Sloughing of necrotic tissue Sloughing of necrotic tissue plugs up the airways plugs up the airways
Can cause partial or complete airway Can cause partial or complete airway obstructionobstruction
Can be fatalCan be fatal
Lung Parenchyma InjuryLung Parenchyma Injury
Pulmonary parenchyma shows:Pulmonary parenchyma shows: Varying degrees of congestionVarying degrees of congestion Interstitial and alveolar edemaInterstitial and alveolar edema Hyaline membranesHyaline membranes Dense atelectasisDense atelectasis
Lung Parenchyma InjuryLung Parenchyma Injury
Systemic effects:Systemic effects: Increase in RAWIncrease in RAW V/Q mismatchV/Q mismatch Increase in oxygen consumptionIncrease in oxygen consumption Decrease in complianceDecrease in compliance Decrease in oxygenationDecrease in oxygenation Decreased surfactant productionDecreased surfactant production
Carbon Monoxide Carbon Monoxide PoisoningPoisoning
Smoke inhalation from all types Smoke inhalation from all types of fires result in significant CO of fires result in significant CO exposure.exposure.
Pulse oximeter do not reflect the Pulse oximeter do not reflect the true oxygen saturation in the true oxygen saturation in the presence of COHB.presence of COHB.
Symptoms- Table 39-1Symptoms- Table 39-1
Clinical ManifestationsClinical Manifestations
Smoke inhalation injury more Smoke inhalation injury more likely in individuals with:likely in individuals with:
History of burn injury in an enclosed History of burn injury in an enclosed spacespace
Appearance of facial burnsAppearance of facial burns Singed nose and facial hairSinged nose and facial hair Erythema of the oropharynx Erythema of the oropharynx Carbonaceous sputumCarbonaceous sputum Debris around the nose, mouth and Debris around the nose, mouth and
pharynxpharynx
BronchoscopyBronchoscopy
Gold standard for diagnosis of Gold standard for diagnosis of inhalation injuryinhalation injury
Provides direct visualization of Provides direct visualization of airwayairway
SootSoot CharringCharring Mucosal erythemaMucosal erythema UlcerationUlceration HemorrhageHemorrhage EdemaEdema inflammationinflammation
ManagementManagement
Oxygen TherapyOxygen Therapy Airway MaintenanceAirway Maintenance Bronchial Hygiene TherapyBronchial Hygiene Therapy Pharmacologic ManagementPharmacologic Management Mechanical VentilationMechanical Ventilation
ConventionalConventional High frequencyHigh frequency
ManagementManagement
Oxygen TherapyOxygen Therapy Initially give 100%Initially give 100%
Wean by blood gas valuesWean by blood gas values
Analyze COHB with co-oxAnalyze COHB with co-ox
ManagementManagement
Airway maintenanceAirway maintenance Intubation by most skilled clinicianIntubation by most skilled clinician
Nasal intubation is easier for securing Nasal intubation is easier for securing
a tube to a burned facea tube to a burned face
Burns to the neck can cause tightening Burns to the neck can cause tightening
of the tissue causing restriction to the of the tissue causing restriction to the
airwayairway Escharotomies to reduce the pressure Escharotomies to reduce the pressure
exerted to the areaexerted to the area
ManagementManagement
Bronchial Hygiene TherapyBronchial Hygiene Therapy Retained secretions can be life threateningRetained secretions can be life threatening
Early ambulationEarly ambulation
Therapeutic coughingTherapeutic coughing
Chest PTChest PT
Airway suctioningAirway suctioning
Therapeutic bronchoscopyTherapeutic bronchoscopy
Pharmacologic agents for retained Pharmacologic agents for retained
secretionssecretions
ManagementManagement
Pharmacological ManagementPharmacological Management Inhalation injury creates intense Inhalation injury creates intense
bronchospasm and wheezingbronchospasm and wheezing Manage with B2 – agonistsManage with B2 – agonists
Racemic epinephrine to promote Racemic epinephrine to promote
vasoconstriction (trx edema), bronchodilation, vasoconstriction (trx edema), bronchodilation,
and breaking up of secretionsand breaking up of secretions
Mucomyst to break down mucus in the airwayMucomyst to break down mucus in the airway
Heparin/mucomyst nebulizer may reduce pts Heparin/mucomyst nebulizer may reduce pts
mortalitymortality
ManagementManagement
Mechanical VentilationMechanical Ventilation For resp failure associated with For resp failure associated with
inhalation injuryinhalation injury
Pts with this type of injury are at Pts with this type of injury are at
increased risk of ventilator associated increased risk of ventilator associated
injuryinjury
ManagementManagement
Conventional Mechanical Conventional Mechanical
VentilationVentilation Start with Vt of 12-15 ml/kgStart with Vt of 12-15 ml/kg
Better outcomes with non conventional Better outcomes with non conventional
modes of ventilation such as:modes of ventilation such as: Pressure limited ventilationPressure limited ventilation
Reduced rate of death with this type of Reduced rate of death with this type of
injury injury
High Frequency High Frequency VentilationVentilation
Provides o2 at lower Provides o2 at lower concentrations and adequate concentrations and adequate ventilation at reduced airway ventilation at reduced airway pressures.pressures.
Reduces barotraumaReduces barotrauma Less incidence of pneumoniaLess incidence of pneumonia Improved PaO2/FiO2 ratioImproved PaO2/FiO2 ratio
ComplicationsComplications
Most common complications are Most common complications are infection and resp failureinfection and resp failure
Barotrauma due to MVBarotrauma due to MV Late complications due to Late complications due to
inflammatory responses of the inflammatory responses of the bodybody
BronchiectasisBronchiectasis Bronchial stenosisBronchial stenosis ETT cuffs erosionETT cuffs erosion
Long Term OutcomesLong Term Outcomes
Most patients have normal lung Most patients have normal lung parenchyma return within 5 parenchyma return within 5 monthsmonths
Children heal slowlyChildren heal slowly PFT changes for up to 8 yearsPFT changes for up to 8 years Altered lung mechanicsAltered lung mechanics Impaired gas exchangeImpaired gas exchange Chest wall scarringChest wall scarring Weak resp musclesWeak resp muscles Some children never regain normal lung Some children never regain normal lung
functionfunction