Shock

Question 1

Compensated Shock, AKA?

Answer 1

Warm or early shock

Question 2

Physiological changes in compensated shock:

Answer 2

• BP remains normal, only sign may be slightly increased CO
• Baroreceptors in aortic arch and carotid sinus sense hypotension and stimulate vasoconstriction and increase in HR
• Chemoreceptors in carotid body respond to cellular acidosis w/ vasoconstriction and respiratory stimulation
• RAAS system activated by decreased kidney perfusion: increased renin secretion, angiotensin II causes vasoconstriction and aldosterone release
• Humoral response = cathecholamine release increasing contractility and vasoconstriction

Question 3

Equation for BP?

CO?

SV?

Answer 3

BP = CO x SVR

CO = (SV x HR)

SV = EDV – ESV

Question 4

Uncompensated shock, aka:

Answer 4

cold, late

Question 5

Signs of end organ damage in patients with late shock:

Answer 5

Decreased urine output causing ARF

Restlessness progressing to agitation to obtundation to coma

Tachypnea leading to respiratory muscle hypoxia causing worsening acidosis and then respiratory failure

Tachycardia causing increased myocardial oxygen demand resulting in increased catecholamines causing more tachycardia and myocardial ischemia

Question 6

Late shock reversible?

Answer 6

Initially reversible, becomes irreversible

Question 7

Essentially absolute definition for hypotension (no matter the baseline) =

Answer 7

SBP < 90 or MAP < 65

Question 8

Cryptic shock =

BP drop suggestive of shock if ptn has baseline hypertension =

Low pressures some people normally live in?

Answer 8

Cryptic shock = normal SBP despite profound tissue hypoxia, normotensive but lactate ≥ 4

Baseline hypertension… drop of > 40mmHg in SBP is suggestive of shock

some patients live in 80s/50s

Question 9

SIRS criteria

Answer 9

Temperature: <96.8 F or >100.4 F

HR: >90

RR: >20 or PCO2 < 32

WBC: < 4 or >12 or bands > 10%

Question 10

Severe sepsis =

Signs of severe sepsis =

Answer 10

SIRS + known infection + organ dysfunction

Elevated creatinine, elevated INR, altered MS, elevated lactate, hypotension responding to IVF

Question 11

Septic Shock =

Answer 11

Severe sepsis, with no response to IVF

Question 12

According to Early Goal Directed Therapy, the key early measure to take in each patient is?

What does this estimate?

Answer 12

CVP

estimates preload

Question 13

Normal CVP?

CVP we want before administering pressors?

Answer 13

Normal = 0-4 mmHg

Want 8-12 mmHg before giving pressors

Question 14

MAP goal according to EGDT?

Most commonly used pressors?

Drug used if MAP too high?

Answer 14

65-90

Vasopressors used most often are norepinephrine and dobutamine

Use vasodilators if too high (nitro)

Question 15

EGDT Goal for ScVO2 (central venous oxygen saturation)

Should we be shooting for normoxia, hypoxia, or hyperoxia and why?

Answer 15

Goal is >70% (manipulate w/ CO and carrying capacity of oxygen)

Normoxia had 20% mortality, but hypoxia had 40% and hyperoxia had 34% (worse outcome if pushing for hyperoxic ScVO2)

Question 16

Goal for lactate for EGDT:

Answer 16

Definitely below 4

but nl is ≤ 2, so 2-4 range is “cryptic”

Question 17

Describe “Time to Antibiotic” idea:

Answer 17

Early ABX initiation is key: 7.6% absolute increase in mortality per hour