Submersion/Environmental (1305) Flashcards
What population is predominantly impacted with drowning?
Children <5 or youth ages
Males
Alcohol & drug intoxication
Disorders that can cause LOC (seizure)
What is drowning defined as?
Respiratory failure due to submersion (airway below liquid) or immersion (airway above liquid)
Patho of drowning?
- Starts with breath holding. Hypercapnia overrides voluntary urge to hold your breath (55 mmHg)
- Coughing occurs, causing swallowing large amounts of water
- Gasping due to LOC occurs
- Once water enters pharynx and/or trachea, victim will suffer laryngospasm (can be perm or temp)
- Spasm permanent? No aspiration
- Spasm temporary? Fluid enters lungs; increases hypercapnia and hypoxia - arrest
- Progression is tachy, brady, PEA, asystole
Saltwater vs Freshwater?
Fresh water has lower osmolarity. If large amounts consumed, blood volumes increase causing breakdown of RBC’s.
Does NOT occur with salt water cause osmolarity is relatively equal.
What happens if water is polluted/sewage is present?
Patient will need antibiotics for pulmonary infections
What is cold water drowning?
When the mammalian diving reflex is triggered.
- Causes bradycardia, peripheral vasoconstriction, and reduced O2 demand.
- Reflex is more pronounced in pediatrics
What is secondary drowning?
When small amounts of aspirated water are either reabsorbed in vasculature or decreases lung compliance. This results in loss of surfactant, atelectasis, and hypoxia.
Can be immediate or delayed 4-8 hours
What is ARDS?
Impacts alveoli/capillaries causing increased capillary permeability.
- Leads to non-cardiogenic pulmonary edema
- Eventually transitions to atelectasis (collapse of lung), decreased lung capacity, V/Q mismatch and hypoxia
Drowning management?
Manage ABC’s and treat as medical cardiac arrest (UNLESS HYPOTHERMIC)
- Get a GOOD history gathering. Condition of water, temperature of water, duration of submersion, etc
What is barotrauma?
Injury to the body due to changes in barometric (air) or water pressure
How much is ATA?
Atmosphere absolute?
How much does depth increase when you increase ATA in increments of 1?
33
(ex: 2 ATA = 33 feet, 3 ATA = 66 feet)
What is Boyle’s Law?
Pressure of gas has an inverse relationship with its volume
What is Dalton’s Law?
Total pressure of gas equals sum of partial pressures of ALL gases
What is Henry’s Law?
Amount of dissolved gas in liquid is proportional to the partial pressure ABOVE liquid when temperature is kept constant
What should you consider with a diver who just resurfaced 10 minutes ago and is now experiencing LOC?
Air embolism
What is Pulmonary Overpressurization Syndrome (POPS)?
When air becomes trapped within lungs from breath holding, bronchospasm, or mucus plugs which all cause alveolar rupture. Happens when a diver makes ascent
What is Decompression SIckness (The Bends)?
When nitrogen compressed in tissues/blood (due to pressure underwater) turns back into gas bubbles when surfacing (Henry’s Law)
These people need hyperbaric chamber and high flow O2 ASAP
What is Nitrogen Narcosis?
When nitrogen becomes dissolved in blood and passes through blood brain barrier
Similar to being drunk off alcohol
What is Thermogenesis?
Production of heat for body via sympathetic nervous system
- Body shunts blood to core via vasoconstriction; causes piloerection
- This traps more air increasing insulation; closes skin pores limiting sweating
- When maximum vasoconstriction has occured, body will start involuntarily shaking
- Lastly, thyroid release hormones to increase metabolic rate in celss (brown fat - only plays a role in very young people)
What is Thermolysis?
Release of stored heat from body via parasympathetic nervous system
- Vasodilation occurs, releasing heat and causes diaphoresis
- Decreases demand from thyroid and adrenals
4 Main Types of Heat Related Injuries?
Heat Syncope, Cramps, Exhaustion, Stroke
What is Heat Syncope?
Result of hypovolemia from volume depletion and vasodilation.
- Compounded by medications
- Occurs to people who are unacclimated to heat or elderly
- Orthostatic hypotension
What are Heat Cramps?
Mild to severe muscle cramps that are fatigued.
- Imbalance between Na and water loss
- Get electrolytes in these patients asap
- Will present with hot flushed skin, diaphoresis, tachycardia
What is Heat Exhaustion?
More serious than heat cramps. Patients will be hyperthermic (<39 C)
- Patients complain of dizziness, headache, nausea, etc
- Remove from hot environment and supportive care with fluid replacement
What are Heat Strokes?
Most dangerous, temperature >40 C or higher (proteins denature at 41C)
- Can occur from environment, intracranial hemorrhage, overdose
What are Classic Heat Strokes?
Impacts young and elderly due to prolonged heat exposure. Compounded by comobordities and medications
What are Exertional Heat Strokes?
Athletes/military who operate in hot/humid environments; can’t disperse heat fast enough to maintain normal temperatures
What happens with frostbite?
Tissue freezes from ice crystals forming in tissue; often unprotected body parts
- Fluid shifts to extravascular space, blood vessels damaged
- When warmed, blood flow restricted due to microvascular emboli
- Causes hypoxia and tissue death
Types of Frostbite?
Frostnip- mild blanching, mild pain
Superficial- waxy, white skin. Becomes painful during rewarming. Eschar tissue forms, peels away leaving red shiny skin
Deep - black ass skin (no racial), shit’s dead son
At what temperature does the body stop shivering (thermogenesis)?
< 32 C
On an ECG, what can you see in hypothermic patients?
J Wave (Osborn wave)
