Shock

Question 1

What is shock?

Answer 1

Insufficient blood supply to the tissues, to meet their demands

Question 2

What are the 4 main classes of shock?

Answer 2

Cardiogenic
Hypovolaemic
Obstructive
Distributive

Question 3

What does adequate tissue perfusion depend on?

really simple, basic things

Answer 3

Pumping ability of heart
Sufficient blood
Functional and complete vascular system
Tissues that are able to extract and use nutrients

Question 4

Name 3 further types of shock that are more like sub-groups.

Answer 4

Anaphylactic
Septic
Neurogenic

Question 5

What are the issues associated with cardiogenic shock?

Answer 5

Inability of heart to maintain adequate BP

• could be due to:
• – failure of the heart as a pump
• – severe alterations in rhythm –> uncoordinated contraction
• – a mechanical defect (e.g. valve damage)

Question 6

What are the issues associated with hypovolaemic shock?

Answer 6

Decrease in circulatory volume

• could be due to:
• – diminished blood volume
• – loss of whole blood
• – loss of plasma
• – loss of ECF

Question 7

What are the issues associated with obstructive shock?

Answer 7

Inability of the heart to fill adequately
OR
Obstruction to outflow from the heart (valve damage, aortic stenosis, etc.)

Question 8

What are vasomotor effects?

Answer 8

Constriction or dilation

Question 9

What are the issues associated with distributive shock?

Answer 9

Loss of sympathetic vasomotor tone
Presence of vasodilators in the blood (e.g. histamine)
Shunting of vascular fluid to interstitial spaces
Arterio-venous shunting
Failure of the cells to use oxygen (e.g. poison)