Shock Flashcards
what is the definition of shock
Tissue Hypoperfusion due to Circulatory Failure
how can you calculate Mean Arterial Pressure
MAP = 1/3 (SBP – DBP) + DBP
OR
MAP = SBP + 2 (DBP) / 3
what happens in hypoperfusion
systemic acidosis (pH<7.35)
worsening global enzyme function and cellular performance
micro capillary thrombus
- causes mottling
what affects MAP
Cardiac output
and
Systemic vascular resistance
what affects CO
Heart rate
Stroke Volume
what happens in cardiogenic shock
Reduced force of cardiac contraction and stroke volume and therefore cardiac output and mean arterial pressure
Increased in SVR
what happens in cardiogenic shock
patients get cool, clammy peripheries
what happens in obstructive shock
Obstruction to cardiac outflow (otherwise similar to cardiogenic shock)
Evidence of raised JVP and Distended Neck Veins may be prominent
what can cause obstructive shock
cardiac tamponade
tension pneumothorax
pulmonary embolus
what happens in hypovolaemic shock
Reduced blood volume
Lower venous return to the heart (ventricular filling = end-diastolic volume)
Reduced force of cardiac contraction and Cardiac Output
what sign is seen in hypovolaemic shock
tachycardia
what is seen in distributive shock
Reduced systemic Vascular Resistance due to Vasodilatation with WARM, RED PERIPHERIES
Reduced Mean Arterial Pressure
Compensatory increase in Cardiac Output
what signs are seen in a patient with distributive shock
warm, red peripheries
bounding, hyperdynamic circulation
what type of shock presents “cold”
hypovolaemic shock
what causes distributive shock
sepsis
anaphylactic shock
spinal cord damage
iatrogenic
