Environmental injuries - Heat stroke - Frost bite - Submersion

1. (submersion, body temp extremes,
thermal injuries)

2. Drowning: asphyxiation caused by submersion
in a liquid that causes interruption of the body’s
oxygen absorption
Near-drowning: a term formerly used to describe
victim’s survival at least 24 hours after submersion
(8000 deaths per year in the United States; 20 - 25%
are children)

3.  Wet drowning: Aspiration of water into airways and
lungs. This leads to destruction of surfactant, alveolar
instability, non-cardiogenic pulmonary edema, and
impaired gas exchange.
 Dry drowning: Severe para-sympathetically
mediated laryngospasm
 Both types result in common pathway of hypoxia
which leads to acidosis, cardiac arrest, and brain death

4. 1. Drug and alcohol intoxication
2. Cardiac arrest
3. Hypoglycemia
4. Seizure
5. Suicidal or homicidal behavior
6. Child abuse

5.  Hypoxia
 Vomiting:
 66% of victims who receive rescue breaths vomit
 86% of victims who require chest compressions and
ventilations vomit
 Mental status changes, tachycardia, cardiac
arrhythmias, tachypnea, wheezing, pulmonary
edema, cyanosis, apnea
 Diving injuries:
 Potential head or cervical spine injury must be considered

6.  Arterial blood gas (ABG)
 Serum electrolytes
 Blood sugar levels
 Chest X-ray (CXR)

7.  Rescue breathing
 Airway management
 Air way and Oxygen inhalation
 Endotracheal intubation (if required)
 Non-invasive ventilatory support
 Serial ABGs traditionally used to guide need for
ventilatory support

8. Thermoregulation: ability to maintain normal
body temperature at physiologic levels despite
changes in external environmental temperature

9.  Heat conservation - Shivering, vasoconstriction, and piloerection
 Cooling - Transfer of heat via electromagnetic waves from body
to cooler air
 Evaporation - Heat loss by perspiration, breathing, saliva;
Acetylcholine regulates sweat glands and is impaired by
anticholinergic drugs
 Convection (8%)
 Transfer of heat from body to fluid, surrounding air or water vapor
 Wind or “wind chill” is an example
 Conduction (2%)
 Direct transfer of heat via physical contact

10.  Normal: 97.7°F to 98.6°F (36.5°C to 37°C)
 Mild: 93.2°F to 96.8°F (34°C to 36°C)
 Moderate: 86°F to 93.2°F (30°C to 34°C)
 Severe: <86°F (< 30°C)

11.  Environmental exposure
 Toxicologic—mnemonic COOLS
 Carbon monoxide
 Oral hypoglycemics
 Opioids
 Liquors
 Sedatives
 Systemic
 Sepsis, hypothyroidism, hypo-adrenalism,
malnutrition, central nervous system (CNS) injury

12.  Shivering
 Confusion
 Poor judgment
 Tachycardia and tachypnoea
 Dilated pupils
 “Shivering”
 Cold diuresis
 Bradycardia and slow atrial fibrillation
 < 82°F (< 28°C)—patient may appear dead
(unresponsive, fixed pupils, apnoeic)
 Asystole and ventricular fibrillation is common

13. a. Pancreatitis
b. Acute tubular necrosis/ renal failure
c. Rhabdomyolysis
d. Disseminated intravascular coagulopathy
(DIC)
e. Acute respiratory distress syndrome

14.  Temperature
 Rectal probe for continuous temperature monitoring
 Warm patients to normal or near normal body temperature
before declaring them dead
 Laboratory tests
 ABG
 Elevated pH
 Low PCO2
 Complete blood count (CBC)
 Coagulation profile prolonged and evidence of DIC
 Creatinine kinase may be elevated with rhabdomyolysis
 Amylase or lipase may be elevated with pancreatitis

16. Rewarming methods
 Remove wet and cold garments
 Cover with warm blanket
 Cardiac monitoring
 Observe for arrythmias
Rewarming techniques
 Passive re-warming
(Cover with blanket)
 Active external rewarming
 Forced hot air, warming blanket
 Re-warming trunk
 Active internal rewarming
 Warm IV fluids to 115°F (45°C)
 Warm humidified oxygen

17. Unstable patients
 Start CPR
 Defibrillate
 Oxygenation and
Ventilation

18. Epidemiology:
 The elderly, very young, or chronically ill are vulnerable to hyperthermia
 Exertional heat stroke is second leading cause of sports-related mortality.
Etiology
 Inefficient evaporation
 Evaporation ceases when humidity approaches 100%
 Lack of acclimatization
 Impaired sweating
 Toxicologic
 Sympathomimetics (amphetamine, cocaine)
 Neuroleptic malignant syndrome, serotonin syndrome, malignant hyperthermia
 Anticholinergics
 Salicylate poisoning
 Systemic conditions
 Hyperthyroidism, sepsis, pheochromocytoma

19. Heat cramps Heat exhaustion Heat stroke
 Heat cramps
 muscle cramping usually affecting the calves and abdomen
 Heat exhaustion
 Weakness, headache, nausea and vomiting caused by dehydration
 Heat stroke
 Temperature >106°F (41°C)
 Organ damage
 Coma
 Anhidrosis

20.  Rhabdomyolysis
 Compartment syndrome
 Liver failure
 Seizure
 Arrhythmias
 Pulmonary edema /ARDS
 Acute renal failure
 DIC

21.  CBC, CPK, glucose, BUN/creatinine, and LFTs
 CXR to rule out pulmonary edema
 Head CT and lumbar puncture may be required to
differentiate encephalitis/meningitis from heat
stroke
Management
 Hydration
 Rapid cooling
 Mechanical cooling
 Pharmacologic
 Antipyretics have no role.
 Bezodiazepines to manage agitation and shivering

22.  Systemic inflammatory response Inflammatory mediators (ie,
leukotrienes) released, triggering inflammatory cascade
 Cardiac Nonspecific electrocardiographic changes
 Myocardial enzyme elevations possible
 Neurologic Mental status alteration
 Outcome related to time with elevated temperature
 Permanent cerebellar injury may result
 Renal Acute renal failure in 10%
 Injury is secondary to myoglobinuria, direct injury to tubules, and volume depletion
 Skeletal muscle Rhabdomyolysis
 Elevated CPK
 Hyperkalemia when myocytes destroyed
 Hypocalcemia
 Gastrointestinal Vomiting
 Diarrhea
 Coagulation Direct injury to clotting factors
 Disseminated intravascular coagulation (DIC)
 Acute liver injury, often

23.  Frostbite: Tissue injury due to prolonged
exposure to below freezing temperatures (<32°F,
0°C)
 Frost nip: mild, reversible superficial cold injury
 Trench foot: prolonged wet, cold but non-freezing
exposure causing reversible neurovascular injury
 Chilblain: skin injury consisting of painful edema,
erythema, and plaques caused by repeated dry,
cold but nonfreezing exposure

24. Vasoconstriction
decreased delivery of warm blood to extremities and
formation of ice crystals in tissue
Sludging at capillary level and microvascular
thrombosis
Reperfusion injury occurs when frozen tissue thaws

25.  Erythema and edema
 Clear blisters
 Hemorrhagic bullae
 Pale grey extremity
 Severe pain with rewarming
 Ultimately becomes painless with loss of all
sensations

26.  Rewarming
 Thawing in warm water 104°F to 108°F (40°C to 42°C)
 Endpoint of thawing is a warm and soft extremity
 Wound care
 Unroof clear blisters rich in injurious thromboxane
 Do not unroof hemorrhagic blisters
 Topical aloe vera over all affected areas
 Anti-tetanus vaccine
 Antibiotics if infection or penetrating wound
 Consultation with surgery /amputation

27. Degree Thickness Exam
1st Epidermis Erythema, tenderness, pain
Sunburn
No blisters
2nd Epidermis/Derm
is
Very painful unless deep second-degree burn
Superficial partial thickness : Skin is red and
blanches with pressure
Deep partial thickness: Blisters, which usually
rupture
if not promptly cared for
3rd All skin Layers Pale, leathery appearance
Insensate secondary to destruction of nerve
endings and blood supply
4th Skin, fascia,
muscle, tendon,
bone
Correlated to the severity and the extent of
involvement of underlying subcutaneous tissue

29. Fluid management
 Parkland formula: 4 mL/kg × % total BSA burned (in
pediatrics give 3 mL/kg)
 50% given in the first 8 hours and remainder over 16 hours
 Ringer lactate is preferred IV fluid
 Maintain urine output at a minimum of 1 mL/kg/h
Transfer to burn center if
 >10% BSA of partial thickness degree burns Third-
degree burn (guidelines do not specify BSA)
 Second- or third-degree burns of hands, feet, genitalia,
perineum, or over joints
 Electrical, chemical, or inhalation injury
 Significant comorbid conditions

30.  Blisters should be left intact
 Apply silver sulfadiazine
 Open wounds should be covered with sterile saline-
soaked gauze
 Anti-tetanus vaccine
 Suspect inhalation injury if:
 Sore throat and dyspnoea
 Stridor with airway edema
 Soot or burns to the nasopharynx
 Singed facial or nasal hair
 Carbonaceous sputum
 Strongly consider prophylactic intubation