Shock Pathophys

Question 1

What happens when the body switches to the anaerobic respiration?

Answer 1

-Lactate increases
- change in blood pH- lactic acidosis

Question 2

What happens in shock?

Answer 2

inadequate oxygen and nutrient supply to the cells

Question 3

BP= (HR x _____ ______) x Systemic vascular resistance

Answer 3

stroke volume

Question 4

Put these stages of shock in order:
- progressive shock
- initial stage
- refractory shock
- compensation/nonprogressive

Answer 4

1. initial stage, 2. compensation/nonprogressive, 3. progressive shock, 4. refractory shock

Question 5

What happens in the inital stage of shock?

Answer 5

Cells are being starved of O2, reduced production of ATP for energy, switch to anaerobic metabolism- lactic acid is produced. No clinical signs to observe or document.

Question 6

What happens in the compensation (non-progressive) stage of shock?

Answer 6

• initial detection of reduced perfusion, activation of compensatory (homeostatic) mechanisms- cardiovascular, renal and endocrine compensation. Outward clinical signs- respiratory, cardiovascular, renal and skin.

Question 7

Cardiovascular Compensation:
1. __________ respond to stretch of the arterial walls.
2. __________ in the left ventricle output results in activation of baroreceptors.
3. Activates baroreceptor ________

Answer 7

1. Baroreceptors
2. decrease
3. reflex

Question 8

Name 5 cardiovascular clinical observations of shock

Answer 8

• increased HR (tachycardia)
• pale, clammy, cold skin (vasoconstriction)
• decrease pulse pressure (Weak Pulse)
• NO change in BP (its being compensated)
• all these trying to return the arterial pressure back to normal.

Question 9

What does the antidiuretic hormone (ADH) do?

Answer 9

water retention, vasoconstrict blood vessels, to maintain or increase BP

Question 10

Effect of Shock on Gas Exchange:
- efficient gas exchange requires sufficient _______ and _______

Answer 10

• ventilation and perfusion

Question 11

Shock reduced perfusion= _____ V/Q ratio

Answer 11

high

Question 12

Clinical Signs of Compensatory Shock:
- Cardiovascular- _______, no change in BP
- Renal- ______, kidneys trying to conserve water in the system.
- Skin- ____, clammy, cool
- Respiratory- _______ RR.

Answer 12

• tachycardia
• oliguria
• pale
• increased

Question 13

What happens in the progressive (non-compensated) stage of shock?

Answer 13

• compensatory mechanisms begin to fail- BP falls
• perfusion begins to fail
• metabolic acidosis present
• oxygen deprivation in the brain- confusion
• multiple organ failure- organ damage

Question 14

What happens in refractory shock?

Answer 14

-widespread cell death
- shock cannot be reversed
- death is imminent

Question 15

What is hypovolaemic shock?

Answer 15

• reduction in circulatory volume- hence decrease cardiac output
• Blood loss- trauma, lower GI bleed, AAA, dehydration, PR bleed, oesophageal varices.

Question 16

What is cardiogenic Shock?

Answer 16

• failure of the heart as a pump
• loss of CO- (HR and contractility)

Question 17

Name 3 causes of cariogenic shock

Answer 17

• Major MI
• Severe left ventricular failure
• ischemic heart disease

Question 18

Name 3 causes of hypovolemic shock

Answer 18

• AAA
• Trauma
• Dehydration
• PR bleed
• Lower GI bleed
• Oesophageal varices

Question 19

What is distributive shock?

Answer 19

• inadequate tissue perfusion- lack of normal responsiveness to blood vessels to vasoconstrictive agents, direct vasodialation
• drop in systemic vascular resistance and stroke volume

Question 20

Name 3 examples of distributive shock

Answer 20

• septic- massive vasodilation- less pressure- tissues will not get enough oxygen
• anaphylactic- massive release of histamine from mast cells, increased prostaglandin release, systemic vasodilation
• neurogenic- loss of vasomotor tone and sympathetic activity- e.g spinal cord injury, deep general/spinal anaesthesia, brain damage.

Question 21

What is obstructive shock?

Answer 21

A blockage in blood flow to the heart or major blood vessels.

Question 22

Name 3 causes of obstructive shock

Answer 22

PE, Cardiac tamponade, tension pneumothorax etc.

Question 23

Name 4 symptoms of obstructive shock

Answer 23

• Increased RR
• Tachycardia
• Low BP
• Oliguria