SHOCK STATE (Chart)

Question 1

Define SVR

(Systemic Vascular Resistance)

My Notes (not in textbook)

Answer 1

is defined as the systemic mean arterial blood pressure minus right arterial pressure divided by cardiac output.

MAP - Right Arterial Pressure / CO

Systemic vascular resistance is the quantitative value for left ventricular afterload.

In most patients, changes in vascular resistance reflect changes in arteriolar tone or changes in the viscosity of blood (often secondary to anemia or polycythemia). In patients who are in shock or hypotensive, SVR calculation helps to differentiate among etiologies and can guide therapy. For example, whereas a hypotensive patient with a low SVR may have sepsis, a patient in cardiogenic shock often has hypotension with an elevated SVR

Question 2

Define CVP

(Central Venous Pressure)

Answer 2

Central venous pressure is considered a direct measurement of the blood pressure in the right atrium and vena cava.

Normal CVP is 2-6 mm Hg.

CVP is elevated by :

• overhydration which increases venous return
• heart failure or PA stenosis which limit venous outflow and lead to venous congestion
• positive pressure breathing, straining,

CVP decreases with:

• hypovolemic shock from hemorrhage, fluid shift, dehydration
• negative pressure breathing which occurs when the patient demonstrates retractions or mechanical negative pressure which is sometimes used for high spinal cord injuries.

Question 3

Cardiogenic

(Shock State)

Answer 3

CVP (Central Venous Pressure): Increased

CO (Cardiac Output): Decreased

SVR (Systemic Vascular Resistance: Increased

Question 4

Septic

(Shock State)

Answer 4

CVP (Central Venous Pressure): Decreased

CO (Cardiac Output): Increased then Decreased

SVR (Systemic Vascular Resistance): Decreased

Question 5

Hypovolemic

(Shock State)

Answer 5

CVP (Central Venous Pressure): Decreased

CO (Cardiac Output): Decreased

SVR (Systemic Vascular Resistance): Increased

Question 6