extremes of temperature, drowning, poisoning and overdose Flashcards
How does the body create and lose heat?
created by metabolic and muscle movement.
Lost through conduction, convection, radiation and evaporation.
What happens in the body as hypothermia sets in?
Pulse and respirations becomes slower, and the person becomes unresponsive. Reflex vasoconstriction and increased blood viscosity leads to ischemia and reduced metabolism.
When the core temperature drops, the capillaries and cells membranes become damaged, leading to abnormal fluid movement. This results in hypovolemic shock and cell necrosis.
What are the signs and symptoms of mild hypothermia?
-Temperature of 32-35,
-shivering
-tachycardia
-tachypnoea
-vasoconstriction
-clearly conscious
What are the signs and symptoms of moderate hypothermia?
-Temperature 32-28,
-shivering stops as the body runs out of energy
-cold reduces depolarisation of pacemaker cells; bradycardia
-bradypnoea
-heart arrhythmias
-altered mental state
What are the signs and symptoms of severe hypothermia?
-Temperature <28
-unconcious
-absent breathing
-death
What are the clinical signs of the 5 stages of hypothermia?
I- clearly conscious and shivering
II- Impaired consciousness without shivering
III- unconscious
IV- no breathing
V- death due to irreversible hypothermia
What is the treatment/management for hypothermia?
-CABCDE
-Record temperature
-Re-warm patient: remove wet clothes, heating, foil blanket (Not directly next to skin), blankets
What are the risk factors for hypothermia?
-medical conditions such as hypothyroidism
-intoxicated patients; alcohol causes vasodilation, drugs impact thermoregulation
-exposure to cold, wet, windy environments
-very old or very young
-patients suffering from exhaustion
-injury and immobility
What happens in the body as it becomes hyperthermic?
-the body is producing more heat than it is able to dissipate
-as core body temperature increases, cells start to swell and become more permeable, causing fluid loss and electrolyte imbalances
-enzymes denature, cells break down, organs fail, reduced ability to metabolise
-heat stress-> heat exhaustion -> heat stroke -> multi organ dysfunction
What are the signs and symptoms of heat stress?
-heat oedema- swelling in feet/ankles
-vasodilation and dehydration cause hypotension and syncope
-sodium depletion causes cramps
What are the signs and symptoms of heat exhaustion?
-Headache as brain shrinks away from skull
-dizziness, nausea,
-vomiting due to reduced blood flow to GI tract
-hypotension, sweating, muscle pain, weakness, cramps
- haemoconcentration
hyponatraemia (low sodium levels due to sweating) or hypernatraemia (increased salt concentration due to loss of fluid)
What are the signs and symptoms of heat stroke?
-systemic inflammatory response causes changes in mental function
-hot, dry skin, extreme fatigue, headache, feinting, facial flushing
-cardiovascular dysfunction including arrhythmia and hypotension due to electrolyte imbalances
-respiratory dysfunction as red blood cells change shape and don’t carry as much oxygen
-central nervous system dysfunction including seizures and coma due to reduced blood flow and hypoxia
-liver and renal failure
-coagulopathy as red blood cells change shape
-rhabdomyolysis due to clotting issues
How do you treat/manage hyperthermia?
-move to a cooler environment
-remove clothing layers
-try to cool patient
-be aware cold fluids may send them into shock
-emergency transfer and pre-alert
What is immersion and what can it cause?
-covering the body in liquid.
-causes hypothermia and cardiovascular collapse
-The initial response is gasping, hyperventilation, increased cardiac output, peripheral vasoconstriction.
-hypothermia causes reduced metabolism and muscle fatigue. can also cause loss of consciousness leading to submersion.
What is submersion and what can it cause?
-The entire body and airway being under liquid. Results in asphyxia and hypoxia.
-hydrostatic pressure of water increases blood pressure. When they are removed from the water this can drop. should be kept horizontal.
-initial reaction: holding breath + possible laryngospasm. Leads to hypoxia
-can aspirate water, worsening hypoxia, leading to cardiac arrest
