Shock: General Overview and Approach

Question 1

definition of shock

Answer 1

inadequate tissue perfusion to meet cellular requirements of O2 and nutrtients

Question 2

outline the changes to the vascular system that occurs during stress to ensure oxygen delivery

Answer 2

• increased HR
• increased contractility
• vasoconstriction and vasodilation to enhance blood flow.
• if unable to meet metabolic requirements, leads to end organd dysfunction and clinical evidence of shock.

Question 3

how to blood pressure change in someone who is hsock

Answer 3

usually hypotensive (but not always).

Question 4

how is preload clinically evaluated

Answer 4

JVP or catheter pressures

Question 5

4 broad categories of shock

Answer 5

1. hypovolemic
2. cardiogenic
3. obstructive
4. distributive.

Question 6

primary problem of hypovolemic shock

Answer 6

• reduced preload due to tauma (ex/ traumatic amputation, massive GI bleed)

Question 7

what clinical/physical exam findings are altered when a person has hypovolemic shock

Answer 7

hypovolemic shock is caused by decreased preload, which results in low JVP

Question 8

hypovolemic shock is caused by decreased preload, which results in low JVP. What mechanisms are in place to compensate for the preload reduction?

Answer 8

1. afterload– results in cool extremities
2. contractiliy –>increased CO
3. rate–> tachycardia

Question 9

primary problem causing cardiogenic shock

Answer 9

1. contractilty –>> decreased CO
2. rate –> rachycardia
3. rhythm –>pulse irregularity
   - all cause an elevated JVP.

this can be caused due to MI ex

Question 10

cardiogenic shock is due to decreased CO, tachycardia, and pulse irregulairty causing an elevated JVP and poor system circulation and perfusion. What systems are in place to compensate for the measures of cardiogenic shock?

Answer 10

1. afterload –> cool extremities
2. rate –> tachycardia

Question 11

causes of distributive shock and primary problem of DS.

Answer 11

• usually septic or anaphylaxis

primary problem is reduced afterload. –> warm extremities

compensation is elevated contractiltiy causing increased CO and tachycardia

Question 12

6 main mechanisms of how inadequate perfusion may occur

Answer 12

1. afterload changes
2. changes in rate
3. changes in rhythm
4. changes in preload
5. changes in contractility
6. changes in blood content.

Question 13

causes of obstructive shock and primary problems of obstructive shock

Answer 13

• can be due to PE or pulmonary hypertension
• primary problem is due to reduced contractility (decreased CO) or elevated preload (elevated JVP)

compensated due to afterload (cool extremities) and rate (tachy

Question 14

two types of shock that result in high JVP elevation

Answer 14

• cardiogenic
• obstructive.

Question 15

type of shock that has warm extremities

Answer 15

distributive shock

Question 16

two types of shock with low JVP

Answer 16

• hypovolemic shock
• decompensated distributive.

Question 17

initial workup for shock

Answer 17

1. history
2. physical exam
3. investigations; abg, cbc, lytes, creatinine, glucose, ECG, CXR

Question 18

clinical manifestations of shock

Answer 18

Question 19

Six Physiologic Factors to Optimize in the Management of Shock (PRRCAC)

Answer 19

Preload

Rate

Rhythm

Contractility

Afterload
Content

Question 20

adequad preload is essential for cardiac output. You must assess JVP or CVP, or if necessary use echo or PAC.

too little preload –> administer ___

too much preload –> administer ___,___

Answer 20

too little: administer fluids

too much preload ; administer diuretics or venodilators

Question 21

how should you give fluids to someone in preload?

Answer 21

BOLUS– not infusion.

Question 22

Rate
 Too fast: -usually need to treat the
underlying cause -may need rate-controlling agent
or cardioversion
 Too slow: -administer __, ___, pacing
(transcutaneous or transvenous)

Answer 22

Rate
 Too fast: -usually need to treat the
underlying cause -may need rate-controlling agent
or cardioversion
 Too slow: -atropine, epinephrine, pacing
(transcutaneous or transvenous)

Question 23

contractility can be assessed with ___.

inadequate contractility can be treated by:

Answer 23

assessed with echo

• trated by inotropes, optimize oxygen delivery to myocardium, correct metabolic derangements

Question 24

Afterload
 Assess through clinical exam
 Too much: ___, typically in
combination with fluids +/- inotropic
agent
 Too little: ___

Answer 24

Afterload
 Assess through clinical exam
 Too much: vasodilators, typically in
combination with fluids +/- inotropic
agent
 Too little: vasoconstrictors