Shock Flashcards
when O2 supply< O2 demand and leads to organ dysfunction
shock
OER (O2 extraction)=
VO2/DO2
VO2=
CO(CaO2-CvO2)
DO2=
COxCaO2
what happens if cardiac output (CO) decreases
DO2 and VO2 decrease
total O2 content in arterial blood
CaO2
CaO2=
(Hbx1.34xSaO2/100)+(0.003xPaO2)
depends on pulmonary gas exchange
PaO2
the supply of O2 depends on
CaO2
systemic O2 demand increases in what situations
stress, pain, fever, exercise
shock that has decrease in blood volume and CO
Hypovolemic shock
2 types of hypovolemic shock
hemorrhagic and fluid loss
2 types of hemorrhagic hypovolemic shock
traumatic: spleen rupture
non-traumatic: bleeding ulcer
types of fluid loss hypovolemic shock
diarrhea, vomiting
burn
ascites
polyuria
type of shock dealing w/ heart not functioning properly
cardiogenic shock
main ways cardiogenic shock can happen
MI
myocarditis
arrythmia
aortic and mitral regurgitation
shock due to blood not flowing (venodilation)
distributive shock
most common form of shock and fatal form
septic shock
3 main types of distributive shock
septic
anaphylactic
neurogenic
shock due to diastolic filling not happening due to restriction
obstructive shock
tension pneumothorax
cardiac tamponade
restrictive pericarditis
pulmonary embolism
aortic dissection
all lead to what shock
obstructive shock
best example of obstructive shock due to fluid in pericardial sac
cardiac tamponade
leads to obstructive shock due to L ventricle basically empty due to oxygenated blood unable to come back from lungs
pulmonary embolism
shock due to O2 not being able to be utilized/consumed
Dissociative shock
2 main things that can lead to dissociative shock
CO poisoning
Cyanide poisoning
contractility (inotropy) of heart depends on what
Ca2+ sensitivity and binding to troponin C
sarcomere length based on diastolic filling (preload)
Starling effect
preload is measured by what
pulmonary artery catheter
end diastolic sarcomere length=
preload
how to measure pulmonary capillary wedge pressure
catheter goes from SVC all the way to pulmonary a. and is measured based on end diastolic sarcomere length
decrease in SVR (primary); CO increases (secondary)
distributive shock
decrease in CO (primary); SVR increases (secondary)
cardiogenic shock
obstructive shock
hypovolemic shock
difference b/t cardiogenic LV and cardiogenic RV shock
cardiogenic LV has increased PCWP (wedge pressure)
cardiogenic RV has decreased PCWP (wedge pressure)
ultimately what happens to compensate in shock
baroreceptor reflex and chemosensors respond (sympathetic activation)
one of the earliest and very important signs of shock (most sensitive indicator of shock)
tachycardia
what happens to HbO2 curve to compensate for shock
shifts to the R (O2 unloading)
when DO2 decreases in shock, what compensates
increase in OER (O2 extraction)
what happens if increasing OER doesn’t meet systemic O2 demands
switch metabolism to anaerobic (lactic acidosis)
critical lab to order and diagnose shock
lactate
stage of shock that is reversible; tissue hypoperfusion
compensated
stage of shock where there is vital organ failure
progressive