Shock Flashcards
Is shock a disease or a syndrome?
Syndrome associated with many disease conditions
what are the 10 clinical signs of shock
- decreased mentation
- cool extremities/hypothermia
- poor peripheral pulses
- prolonged CRT
- pale MM
- tachycardia in dogs/bradycardia in cats
- increased RR and effort
- decreased BP
- decreased urine production
- GI ulceration/decreased GI blood flow
what are the 3 hallmarks of FELINE shock
- bradycardia
- hypothermia
- hypotension
You have a cat presenting with hypothermia, bradycardia and hypotension… Understanding that hypothermia decreases the ability to cope with fluid load, what is your next step?
Start fluid resuscitation but do not blast with fluids until you determine the patients response to rewarming
what is the physiologic response to shock
- increased sympathetic output (release of E/NE)
- increase in HR, cardiac contractility and vasoconstriction
describe the vasoconstriction that happens during shock, what receptors are key?
vasoconstriction of organs with high numbers of α1 receptors (sphanchnic organs, kidneys, skin, skeletal mm) but maintenance of perfusion to the carotid, hepatic and coronary arteries
in terms of endocrine responses, what occurs within:
- IMMEDIATELY
- MINUTES
- HOURS
IMMEDIATELY: release of NE/E from the adrenal gland and vasomotor endplates
MINUTES: release of ADH from pituitary to increase water conservation (increase blood volume)
HOURS: activation of RAAS in kidneys to conserve Na and water (increase blood volume)
what are the 3 STAGES of shock
1) early compensatory
2) early decompensatory
3) late decompensatory/terminal
what are the signs of early compensatory shock
- TACHYCARDIA
- normal to elevated BP
- hyperemic MM
- normal to increased pulses
- CRT < 1s
what are the clinical signs of early decompensatory shock
the same as the general signs of shock:
- tachycardia
- tachypnea
- pale MM
- CRT prolonged
- decreased mentation
- hypotension
- hypothermia
- poor peripheral pulses
what is happening during early decompensatory shock
the compensatory mechanisms are tiring; redistribution of blood from the GI, skin, kidney, mm
what are the clinical signs of late decompensatory shock
- absent CRT
- weak/absent pulses
- decreased HR
- pale/cyanotic MM
- mentally unresponsive/coma
- severe hypotension
- hypothermia
- no urine production
what is the prognosis to the different stages of shock
- early compensatory: good response to volume replacement, good outcome
- early decompensatory: fair to good with immediate intervention
- late decompensatory: poor, generally irreversible
what are the 4 TYPES of shock
1) hypovolemic
2) cardiogenic
3) obstructive
4) distributive (= hyperdynamic)
T/F a patient can suffer from more than 1 category of shock
T
hypovolemic shock is characterized by
profound decrease in intravascular blood volume; generally loss of >30-40% blood volume or >10-15% dehydration
what are the 2 etiologies of hypovolemic shock
1) blood loss/hemorrhage (internal or external)
2) dehydration (burns, GI, polyuria, 3rd space losses)
what are the fluid shifts during hypovolemic shock
to address the hypoperfusion of tissues, fluid shifts from the interstitial/intracellular spaces to the intravascular spaces
what happens during phase 1 of hypovolemic shock
1) water moves from interstitial space to intravascular space, diluting PCV and TS
2) splenic contraction in dogs/horses raises PCV slightly
what are indicators of BLEEDING in a trauma patient on bloodwork
low TS and normal PCV
what are signs of CONTINUED hemorrhage in a patient on bloodwork
low TS and dropping PCV
what happens during phase 2 of hypovolemic shock and what do we see on the blood work
water retention via activation of RAAS -> further drop in PCV/TS
what is obstructive/non-cardiogenic shock
diminished CO secondary to compression of vascular system or obstruction to blood flow
what does obstructive shock behave like
hypovolemic shock