Shock

Question 1

What is shock?

Answer 1

the clinical syndrome of tissue hypoperfusion due to circulatory failure

Question 2

What MAP is required for tissue perfusion?

Answer 2

50-60mmHg

Question 3

What is mean arterial pressure?

Answer 3

average pressure in patients arteries in a cardiac cycle

Question 4

How is MAP calculated?

Answer 4

1/3rd (pulse pressure) + DBP or (SBP + sDBP)/3

Question 5

How is pulse pressure calculated?

Answer 5

SBP-DBP

Question 6

What is the result of inadequate perfusion?

Answer 6

systemic acidosis- bad for enzymes; microcapillary thrombus; eventual cellular necrosis

Question 7

What is seen dermatologically with macro circulatory changes?

Answer 7

mottling of lower limbs: degree correlates with mortality

Question 8

What are the isigns of hypoperfusion?

Answer 8

mottling; GCS; UO <0.5ml/kg/hr

Question 9

How can shock be tested for?

Answer 9

lactate

Question 10

Why might lactate be very low in a very shocked patient?

Answer 10

perfusion is so bad that lactate isn’t getting into the bloodstream

Question 11

What 2 things contribute to MAP?

Answer 11

CO and systemic vascular resistance

Question 12

What is cardiogenic shock?

Answer 12

reduced force of cardiac contraction—CO and MAP

Question 13

What are the peripheries like in cardiogenic shock and why?

Answer 13

compensatory inc. in SVR so cool clammy peripheries

Question 14

What is obstructive shock?

Answer 14

obstruction to cardiac outflow

Question 15

What are the clinical signs associated with obstructive shock?

Answer 15

raised JVP; distended neck veins

Question 16

What are the causes of obstructive shock?

Answer 16

cardiac tamponade; tension pneumo; PE

Question 17

What is hypovolaemic shock?

Answer 17

reduced blood volume—dec. venous return–reduced cardiac contraction

Question 18

What is seen clinically with hypovolaemic shock?

Answer 18

tachycardia; cool clammy peripheries

Question 19

Why does resp rate increase in shock?

Answer 19

compensate for acidosis

Question 20

What is distributive shock?

Answer 20

reduced SVR due to vasodilation; reduced MAP–increase CO

Question 21

What is the difference between peripheries in distributive shock and other types of shock?

Answer 21

warm and red peripheries vs cold and clammy

Question 22

What is the most common type of distributive shock?

Answer 22

sepsis

Question 23

What are the main types of distributive shock?

Answer 23

septic; anaphylactic; neurogenic

Question 24

What are the results of fluid challenge?

Answer 24

if good systolic function: SV will increase if bad function- no inc. in SV after volume expansion