Shock Flashcards
shock is a _____
condition
shock is a lack of _____ and ____
perfusion and oxygenation
this is no perfusion of organs
inability to oxygenate the rest of the body
hypoxic
what is perfusion
- how good the blood flow is to the body
- *BP, color, warmth
- MAP (mean arterial pressure)
if this is maintained, there is good perfusion
MAP
describe oxedated phosporylation
- usually 36-38 molecules of ATP
- if NO oxygen, anaerobic cycle produces 2 molecules of ATP
- cannot survive on this
what is the MAP formula
systolic + diastolic (2) / 3
MAP must be what
> 70 for good perfusion to extremities, kidneys, liver, and lungs
if workload is increased….
need higher MAP
what is the oxygenated cycle
- lungs
- coronary arteries of heart
- carotid artery
- kidneys (1/4 blood supply)
- liver (2/3 of blood supply)
why do you go into shock
d/t no oxygen to organs and eventually heart and lungs
what is the SV
stroke volume
- systolic - diastolic
- normal SV=50-60
- amount of blood per beat that you can push out
what can SV be manipulated by
vasoconstriction
what occurs when you initially go into shock
- get cold
- blood starts SHUNTING UP (no longer in extremities)
- vasoconstriction pushes blood to liver, heart, and lungs (eventually only heart)
what factors influence MAP
1) total blood volume
2) cardiac output
3) size of vascular bed
what is the C.O formula
SV x HR
what is normal C.O
4-6 L
describe afterload
systolic
force heart has to push to get blood out (push of blood from left ventricle to aorta)
describe preload
diastolic
left ventricle and diastolic volume, how much blood left after heart pushes out blood
-never pushes all out (leftover blood)
describe ejection fraction
the % you push out
normal is 65-75%
if heart is working well you push this amount of blood out of the heart
pt with CHF or MI will have a decreased
ejection fraction
no/bad C.O. (may be as low as 20%)
describe size of vascular bed
where does the blood have to go
in septic shock, dilation of vessels is not enough blood flow
what are the 4 types of shock
- hypovolemic
- cardiogenic
- distributive
- obstructive
describe hypovolemic shock
- total body fluid is decreased
- lost blood or fluid (cannot maintain C.O.)
- hemorrhage and dehydration
- easy to fix, give more fluid or blood
describe cardiogenic shock
- pump failure, fluid volume is okay
- no strength to push blood out
- r/t HF (heart not working)
- cannot pump well
describe obstructive shock
- cardiac function is decreased by non cardiac functions
- fluid NOT affected
- clot
- pulmonary HTN, tamponade, pneumothorax, pericarditits
describe distributive shock
- fluid shifted from central vascular space
- body fluid is normal or elevated
- neural or chemical
what is chemical distributive shock
- septic shock
- loss of vascular tone
- lose things to fight infection
what causes shock
-decrease in MAP d/t decrease in C.O, decrease in blood volume or expansion of vascular bed
drop of MAP is detected by what
baroreceptors in the aortic arch and carotid sinus that cause shock process
pt in shock appears
- cold d/t shunting blood (put legs up, elevate)
- gut GI doesnt work
- liver doesnt work (no outward sign)
- kidneys stop working (outward sign is decreased renal output ie/ less than 30 mL/hr)
- head/brain stop working
- heart and lungs stop working
chemical process of shock
- baroreceptors send infor to brian, starts to shunt blood to vital areas
- leads to an increase in lactic acid, protein destroying enzymes and oxygen radicals
how soon does shock need to be reversed before it progresses
in 1 or 2 hrs or may be irreversible and can lead to MODS
what is MODS
multiple organ dysfunction system
d/t lack of oxygen
what do the baroreceptors do
sit on glomerulus and trigger conservation of blood flow, no output
oxygen free radicals attack the heart
