Chapter 40 - Submersion Injury Flashcards
What was the main cause of death in a retrospective study of dogs and cats with submersion injury?
Respiratory failure
What’s the difference between immersion and submersion?
Immersion: airway above water, Submersion: airway under water.
Explain the mechanism of hypovolemia with submersion injury from cold water.
Hypothermia due to large body surface area to mass ratio especially for children/dog/cat than adult. Hypothermia induces peripheral vasoconstriction- redirect blood to central circulation- increased RA pressure- “pseudohypervolemia”. Hypothermia also decrease ADH production and its function in the kidney. The resulting increased diuresis can contribute to development of hypovolemia.
What are the 2 types of autonomic responses to hypothermia?
Cold-shock response & Diving response
Explain cold-shock response
cutaneous cold thermoreceptors induce: sympathetically driven tachycardia, respiratory gasp, and hypertension.
Explain diving response
Sinus bradycardia, expiratory apnea, and peripheral vasoconstriction
What is one of the major causative factors of inability to swim in cold water?
Cold-shock response
What is the one of the reasons why children submerged in very cold water had increased survival? Why?
Diving response: decreases metabolism and increases cerebral perfusion and has the main role of conserving oxygen and extending underwater time.
What is the number one, two organ most commonly affected by drowning?
Lung (hypoxemia due to intrapulmonary shunting of blood through poorly ventilated areas.)
Neuro (hypoxic-ischemic encephalopathy)
What is RECOVER initiative’s conclusion regarding MTH (mild therapeutic hypothermia)?
Mild hypothermia (core temperature of 33 +/- 1C) instituted ASAP after the return of ROSC. Slow rewarming (1-2C/h) preferred over faster ones.
What are the factors found to predict survival and/or recovery with good neurological function in human after drowning?
MGCS. duration of CPR before ROSC. submersion time, time to return to neurological function.
Which one triggers hypoxemia?
victim can no longer hold breath, gasping follows, leading to aspiration of small amount of water, trigger a coughing reflex, laryngospasm, and hypoxemia.
