Shock Flashcards
what is shock
the clinical syndrome of tissue hypoperfusion due to circulatory failure
how can you calculate mean arterial pressure
MAP = 1/3 (systolic - diastolic) + diastolic
MAP = systolic + (2xdiastolic) / 3
pathophysiology of hypo perfusion
Decreased MAP
slow flow to organs
inadequate perfusion for cellular metabolic requirements – leads to acidosis + lactate formation
effects of hypo perfusion
systemic acidosis - pH < 7.35
worsening enzyme function + cellular performance
micro capillary thrombus
- patchy tissue injury
eventually cellular necrosis
what affects MAP
cardiac output
systemic vascular resistance
what affects CO
HR
stroke volume
signs of tissue hypoperfusion
brain- altered mental state
- glasgow coma score < 15
- confusion + agitation
Urine output decrease
Increased lactate levels
mottling due to microcapillary thrombus
what happens in cariogenic shock
reduced force of cardiac contraction + decreased stroke volume
therefore decreased CO + MAP
compensatory increase in systemic vascular resistance
compensatory mechanism in cariogenic shock
increased systemic vascular resistance– cool clammy peripheries
what happens in obstructive shock
obstruction to cardiac outflow
evidence of raised jugular venous pressure + distended neck veins may be prominent
why might you get distended neck veins in obstructive shock
Cardiac output is blocked – venous back pressure – distended neck veins
causes of obstructive shock
cardiac tamponade
tension pneumothorax
PE
what happens in hypovolaemic shock
reduced blood volume
low venous return to the heart
reduced force of cardiac contraction + cardiac output
what sign is seen in hypovolaemic shock
tachycardia
what happens in distributive shock
reduced systemic vascular resistance due to vasodilation – WARM RED PERIPHERIES
reduced MAP
Compensatory Increased in CO
signs of distributive shock
warm red peripheries
bounding, hyper dynamic circulation
types of distributive shock
inflammatory
neurogenic
causes of inflammatory distributive shock
sepsis
pancreatitis
burns
anaphylactic shock
causes of neurogenic distributive shock
spinal cord damage
iatrogenic – epidural
causes of hypovolaemic shock
trauma
Gi bleeding
post- op bleeding
dehydration
causes of cardiogenic shock
arrhythmia MI cardiomyopahty valve failure poisoning
signs of shock
pale, clammy, tachycardia, hypotension, hypoxia
cold peripheries = cariogenic
warm peripheries = distributive
Treatment of shock
GET HELP
IV access
Fluid replacement
Oxygen
Treat cause
