Shock

Question 1

what is shock?

Answer 1

inadequate tissue perfusion to meet metabolic demand and tissue oxygenation

Question 2

what are the physiological categories of shock?

Answer 2

cardiogenic
hypovolemic
distributive
obstructive

Question 3

what are the stages of shock?

Answer 3

compensated
decompensated
irreversible

Question 4

what is compensated shock?

Answer 4

reflex compensatory mechanisms activated and perfusion to vital organs is maintained

*increased HR and BP

Question 5

what is decompensated shock?

Answer 5

tissue hypoperfusion and onset of worsening circulatory and metabolic derangement

• hypotension
• lactic acidosis

Question 6

what is irreversible shock?

Answer 6

organ and tissue injury is so severe that even if hemodynamic effects are corrected, survival is not possible

Question 7

what are the subtypes of distributive shock?

Answer 7

septic

non-septic (inflammatory, anaphylactic, neurogenic)

Question 8

what are the subtypes of cardiogenic shock?

Answer 8

cardiomyopathic
arrhythmogenic
mechanical

Question 9

what are the subtypes of hypovolemic shock?

Answer 9

hemorrhagic

non-hemorrhagic (fluid loss)

Question 10

what are the subtypes of obstructive shock?

Answer 10

pulmonary vascular

mechanical

Question 11

what are the hemodynamic changes of cardiogenic shock?

Answer 11

decreased CO
increased SVR
increased CVP/PCWP

Question 12

what are the hemodynamic changes of hypovolemic shock?

Answer 12

decreased CO
increased SVR
decreased CVP/PCWP

Question 13

what are the hemodynamic changes of septic and anaphylactic shock?

Answer 13

increased CO
decreased SVR
decreased CVP/PCWP

Question 14

what are the hemodynamic changes of neurogenic shock?

Answer 14

decreased CO
decreased SVR
decreased CVP/PCWP

Question 15

what are the hemodynamic changes of obstructive shock?

Answer 15

decreased CO
increased SVR
variable CVP/PCWP

Question 16

what are signs of shock?

Answer 16

hypotension
tachycardia
oliguria
AMS
tachypnea
cold, cyanotic skin
metabolic acidosis
elevated lactate

Question 17

what’s the most important thing to remember with an unstable patient?

Answer 17

Airway
Breathing
Circulation
Disability
Exposure

Question 18

how do you treat shock?

Answer 18

IVFs
vasopressors
US evaluation (RUSH protocol)
broad-spectrum abx (if sepsis suspected)

Question 19

Equation to determine BP

Answer 19

CO x TPR

Question 20

Where is BP the highest?

Answer 20

Proximal Aorta

• hits about 30 mmHg at capillaries
• almost 0 in the RA

Question 21

64% of blood is held where in circulation?

Answer 21

Veins
- SNS decreases venous compliance, shifting blood to the heart and to arterial circulation

• Also a mechanism by which Nitrates work to decrease O2 demand by the cardiac myocytes. Shift the blood more into the veins to decrease preload

Question 22

Possible outcomes of anoxic cells

Answer 22

1. Thrombosis
2. Hemorrhage
3. Edema

Release of inflammatory cytokines IL-1 and TNF

Question 23

2 phases of distributive septic shock

Answer 23

1. Warm shock- High CO but low TPR causing edema. Treat with Fluid resuscitation
2. Cold shock- low CO, high TPR causing hypo perfusion. Skin is cold and petechiae form.

Question 24

What is the mainstay treatment for hypotension in the absence of cariogenic shock (aka pump failure)

Answer 24

Give IVF to raise JVP!

Question 25

Review Anaphylactic Shock

Answer 25

1. IgE-mediated (type I hypersensitivity) 2. Mast cell degranulation (Histamine, Leukotrienes, PGe's) 3. Vasodilation, bronchoconstriction 4. Can cause ACS Tx: Epi +/- Antihistamine +/- Albuterol

Question 26

At what stage of hypovolemic shock do you typically start to give blood products instead of just saline?

Answer 26

Class III aka >30% blood loss | - Drugs typically not needed

Question 27

Typical inotropes/Vasopressers to give in shock

Answer 27

1. Dobutamine (B1 agonist) 2. Epi (all receptors) 3. NE (all - B2) 4. DA 5. Phenylephrine 6. Vasopressin (want V1 receptor activation in vasculature, not V2 in kidney where ADH acts)

Question 28

Common causes of cardiogenic shock aka pump failure

Answer 28

MI Arrhythmias Valvular Dz

Question 29

Describe how Systolic dysfunction progresses to failure and death

Answer 29

1. Decreased CO (reduced EF) 2. Decreased perfusion of coronary and peripheral vessels 3. Compensatory vasoconstriction 4. Progressive failure

Question 30

Describe how diastolic dysfunction progresses to failure and death

Answer 30

1. Increased LVEDP (Left Ventricle End Diastolic Pressure) 2. Pulmonary Congestion due to back up 3. Hypoxemia 4. Ischemia 5. Progressive failure

Question 31

Primary drug for cardiogenic shock

Answer 31

NE | - Dobutamine can be used when decreased CO in presence of adequate filling

Question 32

Review signs of sepsis

Answer 32

1. Hypotensive 2. Tachycardic 3. Tachypnic 4. edema 5. AMS 6. Fever

Question 33

First choice vasopressor for septic shock

Answer 33

NE +/- Epi Vasopressin can be added Dobutamine if needed

Question 34

What other hormone is necessary to survive critical illness and is elicited by corticosteroid dosage in shock?

Answer 34

Cortisol