324 Approach to shock

Question 1

Shock defined as

Answer 1

clinical syndrome from inadequate tissue perfusion

Question 2

Clinical shock is usually accompanied by hypotension with a value of

Answer 2

MAP < 60 mmHg in previously normotensive person

Question 3

MAP value when autoregulation fails

Answer 3

MAP < 60 mmHg

Question 4

Classification of Shock (7)

Answer 4

Hypovolemic
Traumatic
Cardiogenic - Intrinsive or compressive
Septic - Hyperdynamic or Hypodynamic
Neurogenic
Hypoadrenal

Question 5

Early septic shock is also called as

Answer 5

Hyperdynamic septic shock

Question 6

Late septic shock is also called as

Answer 6

Hypodynamic septic shock

Question 7

Represents a common end-stage pathophysiologic pathway in various forms of shock

Answer 7

Cell membrane dysfunction

Question 8

Released in increased response to adrenergic discharge and reduced perfusion of juxtaglomerular apparatus in the kidney.

Answer 8

Renin

Question 9

Induces the formation of Angiotensin I

Answer 9

Renin

Question 10

An extremely potent VASOCONSTRICTOR and stimulator of aldosterone and vasopressin

Answer 10

Angiotensin II

Question 11

Contributes to the maintenance of intravascular volume by enhancing renal tubular reabsorption of Na

Answer 11

Aldosterone

Question 12

Has a direct action on vascular smooth muscle leading to vasoconstriction; acts on renal tubules to enhance water reabsorption

Answer 12

Vasopressin

Question 13

Three variables that control stroke volume

Answer 13

pre-load (ventricular filling)
afterload (resistance to ventricular ejection)
Myocardial contractility

Question 14

Major determinant of tissue perfusion

Answer 14

Cardiac output

CO = SV x HR

Question 15

Systemic vascular resistance is (increased ? decreased?) in hyperdynamic septic shock and neurogenic shock?

Answer 15

Decreased

Question 16

Serves as dynamic reservoir for autoinfusion of blood

Answer 16

Venous system

Question 17

How does septic shock cause heart failure?

Answer 17

Septic shock -> increase pulmonary vascular resistance -> RIGHT heart failure

Question 18

Renal responses to shock

Answer 18

Conserve salt and water
Decrease renal blood flow
Increase afferent arteriolar resistance
Reduced urine formation (low GFR, increased aldosterone and vasopressin)

Question 19

This diagnostic test will represent an innefficient cycling of substrate with minimal net energy production / measure of anaerobic metabolism and reflects inadequate tissue perfusion

Answer 19

Plasma lactate/ pyruvate ratio

Question 20

TXA2 is a potent _

Answer 20

vasoconstrictors

Contributes to pulmonary hypertension and ATN of shock

Question 21

PGI2 PGE2 are potent _

Answer 21

vasodilators

Question 22

LTB4

Answer 22

A potent neutrophil chemoattractant and secretagogue that stimulates the formation of ROS.

Question 23

Produced by activated macrophages, promotes hypotension, lactic acidosis and respiratory failure

Answer 23

Tumor necrosis factor a

Question 24

PAC / Swan-Ganz catheter did not alter mortality, lenght of stay or cost for ICU. True or false.

Answer 24

True

Question 25

Serves as an approximation of Left atrial pressure

Answer 25

Pulmonary capillary wedge pressure (PCWP)

Question 26

Normal cardiac output per L/min

Answer 26

4-8 L/min

Question 27

Stroke volume per mL /beat

Answer 27

50-100 mL/beat

Question 28

O2 carrying capacity of hemoglobin

Answer 28

1.39 mL/g

Question 29

What type of shock? CVP and PCWP ↓ CO ↓ SVR↑

Answer 29

Hypovolemic Table 324-4 p. 1748

Question 30

What type of shock? CVP and PCWP ↑ CO ↓ SVR↑

Answer 30

Cardiogenic Table 324-4 p. 1748

Question 31

What type of shock? CVP and PCWP ↑↓ CO ↓ SVR↑

Answer 31

Septic shock :Hypodynamic Table 324-4 p. 1748

Question 32

What type of shock? CVP and PCWP ↑↓ CO ↑ SVR (decreased)

Answer 32

Septic shock: Hyperdynamic Table 324-4 p. 1748

Question 33

What type of shock? CVP and PCWP ↓ CO ↓ SVR↓

Answer 33

Neurogenic or Hypoadrenal (In hypoadrenal shock, SVR may be normal) Table 324-4 p. 1748

Question 34

Most common form of shock

Answer 34

Hypovolemic shock

Question 35

Approximately how many blood loss does the patient have if he/she has mild tachycardia, relatively few external signs?

Answer 35

<20%

Question 36

Approximately how many bloodloss does the patient have if he/she has become increasingly anxious, tachycardic, with significant postural hypotension and tachycardia? (BP may be normal on supine position)

Answer 36

20-40%

Question 37

Approximate blood loss if there is hypotension, unstable in supine position, marked tachycardia, oliguria, agitation?

Answer 37

>40%

Question 38

Ominous clinical sign in shock

Answer 38

Mental obtundation/ altered sensorium

Question 39

As the attending physician at the ER, you are considering hypovolemic shock in a patient; what monitoring should you do if patient is unstable, HR >120 and SBP <90?

Answer 39

Central monitoring, do CVP

Question 40

Upon monitoring of a shock patient, you noted that CVP is <15, what is your next step?

Answer 40

Administer colloid/ blood | HCT <30, CVP >15

Question 41

Upon monitoring of a shock patient, you noted that CVP is >15, what is your next step?

Answer 41

ECHO and treat appropriately | Differentials: cardiac dysfunction or tamponade

Question 42

Despite hydration in a Shocky patient, unstable VS and acidosis worsens; what is your next step?

Answer 42

Insert PAC

Question 43

In monitoring a shocky patient, PCWP is <15, what's next?

Answer 43

Administer crystalloid, blood

Question 44

In monitoring a shocky patient, PCWP is 20, what's next?

Answer 44

Administer 500mL boluses until preload and monitor

Question 45

In monitoring a shocky patient, PCWP is >20, what's next?

Answer 45

Give inotropes, do ECHO

Question 46

Infusion of how many Liters salt solution will restore normal hemodynamic parameters?

Answer 46

2-3 L over 20 - 30 minutes.

Question 47

True or false. EARLY administration of component therapy during massive transfusion (FFP and platelets) approacing to a ratio of 1:1 of PRBC/ FFP appears to IMPROVE survival.

Answer 47

True.

Question 48

Pulsus paradoxus defined as

Answer 48

Inspiratory reduction in systolic pressure of >10mmHg

Question 49

Best inotropic agent for Neurogenic shock.

Answer 49

Norepinephrine or Phenylephrine

Question 50

Anesthetic agent which may cause hypoadrenal shock.

Answer 50

Etomidate.

Question 51

Hypoadrenal shock is characterized by (3)

Answer 51

decreased vascular resistance, hypovolemia and reduced cardiac output.

Question 52

Diagnosis of adrenal insufficiency is established by

Answer 52

ACTH stimulation test.

Question 53

Treatment for Hypoadrenal shock - empirically

Answer 53

Dexamethasone 4mg IV | Because unlike hydrocortisone - it does not alter your ACTH test

Question 54

Treatment for hypoadrenal shock - after establishing diagnosis

Answer 54

Hydrocortisone 100mg IV q6

Question 55

Inotropic with simultaneous afterload reduction - minimizing cardiac -o2 consumption increase as cardiac output increases.

Answer 55

Dobutamine

Question 56

Inotropic and chronotropic which supports vascular resistance in those whose blood pressure will not tolerate peripheral vascular dilation.

Answer 56

Dopamine

Question 57

Supports blood pressure through vasoconstriction and increases myocardial oxygen consumption; inotropic without chronotropy.

Answer 57

Norepinephrine.

Question 58

Being used to increase afterload and may better protect vital organ blood flow and prevent pathologic vasodilation.

Answer 58

Arginine-vasopressin.