Exam 2: Ch 20 Shock

Question 1

circulatory shock

Answer 1

hypo-perfusion of organs

too little O2 for cell functions

Question 2

cellular response to circulatory shock

Answer 2

anaerobic metabolism – not enough ATP

Na/K pump fails

cells swell and die

Question 3

compensations for circulatory shock

Answer 3

similar to HF – SNS, RAA

counter-productive over time

Question 4

hypovolemic shock definition and compensations

Answer 4

not enough blood volume in system (15-20% lost)

SNS stimulation increases HR, vasoconstriction, inotrophy, venoconstriction (mobilize blood)

RAA stimulation increases ADH/Aldo to restore circulating volume

Question 5

hypovolemic shock symptoms and treatment

Answer 5

thirst, acidosis, mentation

high HR, systemic vascular resistance, afterload

low BP, venous return, PP, SV, CO, EDV, CVP, PCWP, urine output

give volume

Question 6

causes of hypovolemic shock

Answer 6

hemorrhage

plasma loss from burns

extracellular loss (GI)

Question 7

physiology of hypovolemic shock

Answer 7

15% volume loss well tolerated

after 15%, SNS vasoconstriction maintains BP even though CO is low

PP is narrowed and SVR is high

45% blood loss takes CO and BP to 0

Question 8

cardiogenic shock definition and causes

Answer 8

inadequate pumping of the heart

MI, LV aneurysm, valve dysfunction, ischemia

Question 9

physiology and symptoms of cardiogenic shock

Answer 9

low BP, SV, CO, EF contractility, but high afterload

cyanosis, hypoxia, oliguria, high CVP and PCWP (pulmonary capillary wedge pressure)

Question 10

treatment of cardiogenic shock

Answer 10

up inotropics

nitroprusside (arterial/venous dilator) to dec. after/preload

NTG venous dilator to decrease preload

IABP: intra aortic balloon pump

Question 11

IABP

Answer 11

intra aortic balloon pump used to treat cardiogenic shock

deflates during systole to decrease afterload

inflates during diastole to increase CA blood floow

Question 12

obstructive shock

Answer 12

circulation blocked by an obstuction (pulmonary emboli, tamponade, pneumothorax)

generally Rt HF with high CVP and distended neck veins

Question 13

treatment of obstructive shock

Answer 13

pulmonary emboli may respond to thrombolytics

tamponade requires drainage

pneumothorax requires chest tube

Question 14

distributive shock

Answer 14

blood volume adequate but vessels are dilated

low vessel tone (afterload) –> capacity of vascular space expands and blood can’t fill it

low venous return and low CO

LOW SVR

Question 15

types of distributive shock

Answer 15

neurogenic

anaphylactic

septic

Question 16

nerogenic shock

Answer 16

brain or cord damage causes low SNS output and vasodilation

causes: injury, general or spinal anesthesia, hypoxia

Question 17

anaphylactic shock

Answer 17

reaction causes histamine release and vasodilation

treatment: remove allergen and give epi

Question 18

septic shock

Answer 18

bacterial toxins recruit WBC and release cytokines

cytokines disrupt endothelium and causes vasodilation and capillaries leak protein/fluid

result is severe hypovolemia, arterial and venous dilation

Question 19

treatment of septic shock

Answer 19

antibiotics

give volume (fluid, vasopressors)

insulin returns normal blood sugar to dec. mortality

recombinant protein C is anti-inflammatory and an anticoagulant

Question 20

5 complications of shock

Answer 20

acute lung injury/respiratory distress syndrome (ALI/ARDS)

acute renal failure

GI complications

Disseminated intravascular coagulation (DIC)

multiple organ dysfunction syndrome

Question 21

acute lung injury/respiratory distress syndrome (ALI/ARDS)

Answer 21

shock from trauma/sepsis

hypoxemia, hypercapnea, V/Q mismatch

pulmonary capillaries leak fluid so impaired gas exchange

Question 22

cause of ALI/ARDS and Rx

Answer 22

cause: unknown, maybe endothelial damage

Rx: support respiration with mechanical ventilation, avoid O2 toxicity

Question 23

acute renal failure

Answer 23

shock from trauma/sepsis

renal tubules are vulnerable to ischemia and become nectoric

ATN is the most frequent lesion… may be reversible

Question 24

GI complications

Answer 24

shock decreases mucosal perfusion which leads to ulcers and bleeding

Rx: NG suction, proton-pump inhibitors

Question 25

disseminated intravascular coagulation (DIC)

Answer 25

coagulation pathways become activated throughout circulation

seen in 1/3 to 1/2 of septic shock patients

clots lead to organ failure

platelet and clotting factor depletion leads to hemorrhage

Question 26

treatment of DIC

Answer 26

give platelets and anticoagulants

Question 27

multiple organ dysfunction syndrome

Answer 27

strikes kidney, liver, brain, heart, lungs simultaneously

very high mortality rate

Question 28

can shock be progressive?

Answer 28

yes