Consensus circulatory shock and hemodynamic monitoring

Question 1

How is circulatory shock defined?

Answer 1

life-threatening, generalized form of acute circulatory failure associated with inadequate oxygen utilization by the cells

Question 2

What are the 3 organ systems deemed most helpful to early on identify circl shock

Answer 2

• skin (cutaneous perfusion)
• kidneys (UOP)
• brain (mental status)

Question 3

Is BP required to defined shock? What is the sensitivity of SAP < 95 mm Hg to identify moderate to severe blood loss?

Answer 3

not recommended as defining criteria due to lack of sensitivity

SAP < 95 mm Hg
13% sensitive for moderate blood loss
33% sensitive for severe blood loss

Question 4

How can you use veno-arterial partial pressure of CO2 in circulatory shock?

Answer 4

high differences indicate insufficient blood flow to tissues
i.e., values > 6 mm Hg

Question 5

What is the recommended initial hemodynamic monitoring modality?

Answer 5

echocardiography

before more invasive modalities (e.g., PA catheter)

Question 6

What are recommended BP targets

Answer 6

• initially > 65 mm Hg appropriate but then individualized to patient
• lower in uncontrolled bleeding except if severe head injury
• higher in septic patients with history of hypertension

Question 7

What is the recommended monitoring modality to decide whether to administer inotropic agents?

Answer 7

echocardiogram to assess LV ejection fraction

Question 8

How much should CO increase by if a patient responds adequately to fluids?

When is CO measurement recommended?

Answer 8

by at least 10-15%

CO measurement not recommended for initial therapy response
Recommend CO measurement in patients that are not responding to initial therapy

Question 9

How can you estimate CO with echocardiography?

Answer 9

measure velocity-time integral of the ventricular outflow tract blooe flow (subaortic)
and the area of the duct crossed by this flow

Question 10

Explain E/A versus E/E’ ratios

Answer 10

E/A ratio
- peak doppler velocity of early and late diastolic filling

E/E’ ratio
- doppler velocity of early diastolic mital flow (i.e., diastolic filling) and early diastolic mitral annula velocity

E/E’ ratio < 8 is a good predictor of low LV filling pressure - likely fluid responsive