Disruptions in homeostasis

Question 1

Physiological response to stress

Answer 1

Fight or flight response

• blood vessels dilate, increase in HR, R, and bronchodilation
• blood shunted to heart and brain and away from GI tract
• Increase in gluconeogenesis for increased energy

Question 2

Initial stage of shock

Answer 2

• decrease in cardiac output
• decrease in MAP
• sympathetic nervous system stimulated

Question 3

Compensatory stage of shock

Answer 3

• SNS releases epinephrine
• vasoconstriction, blood shunts to heart and brain
• vasodilation causes decreased BP, increase HR, increased myocardial force, decrease in renal perfusion
• increase in water reabsorption in the kidneys
• restlessness, bounding thready pulse, pale cool skin

Question 4

Progressive stage of shock

Answer 4

• Compensatory mechanisms become ineffective
• decrease in CO
• vasoconstriction causes cellular hypoxia
• metabolic acidosis and lactic acid levels rise
• increase in vasoconstriction forces fluid shift to interstitial space
• hypotensive, weak thready pulse, tachycardia, shallow respirations, cool clammy skin, decrease in temp

Question 5

Irreversible stage of shock

Answer 5

• compensatory mechanisms ineffective
• increase in lactic acid
• increase in capillary permeability
• decrease in intravascular volume
• low perfusion to heart and brain, organ systems fail
• pt is unresponsive, low BP, slow irregular or absent pulses, cheyenne-stokes respirations, cardiac arrest

Question 6

Cardiogenic shock

Answer 6

Inadequate pumping causes a decrease in cardiac output, inadequate perfusion and hypotension. Can be caused by MI, arrhythmias, CHF and myocarditis.

Question 7

Hypovolemic shock

Answer 7

Decrease in intravascular volume leads to decrease in cardiac output and circulating volume.

• class 1 - 15% loss
• class 2 - 16-30% loss
• class 3 - 31-40% loss
• class 4 - greater than 40% loss

Question 8

Causes of hypovolemic shock

Answer 8

1. Hemorrhage
2. Burns
3. Surgery
4. Trauma
5. Dehydration
6. DM or DI
7. Peritonitis
8. Pancreatitis
9. Cirrhosis
10. Pneumothorax

Question 9

Distributive shock

Answer 9

Poor distribution of blood, includes

• anaphylactic shock
• neurogenic shock
• septic shock
• obstructive shock

Question 10

Anaphylactic shock

Answer 10

Antigen-antibody reaction that releases histamines into the bloodstream causing dilation of arterioles and capillary beds and bronchial sensitivity.

Question 11

Neurogenic shock

Answer 11

Vascular resistance with generalized vasodilation. Results from GA, epidural, spinal cord injury.

Question 12

Septic shock

Answer 12

Systemic response to microorganisms int eh blood causing vasodilation

Question 13

Obstructive shock

Answer 13

Physical obstruction that decreases cardiac output

- PE, dissecting aortic aneurism, tension pneumothorax

Question 14

Complications of shock

Answer 14

1. Arrhythmias (MI and HF)
2. ARDS
3. Renal failsure
4. recirculation of bacteria and cellular debris
5. DIC
6. GI ulceration

Question 15

Inflammatory process

Answer 15

Phase 1 - vasoconstriction to prevent bleeding
Phase 2 - Production of exudate
Phase 3 - Damaged cells repaired by regeneration or formation of scar tissue