7. Fluid and Hemodynamics

Question 1

What is the first step of treatment in hypovolemia?

Answer 1

Normal saline! to stabilize the BP

Question 2

After you stabilize a hypovolemic patient with normal saline, what do you do now?

Answer 2

Figure out what kind of fluid they initially lost (isotonic vs. hypertonic vs. hypotonic) and replete with that kind of fluid

Question 3

What is the most common cause of sepsis?

Answer 3

E. coli from indwelling catheter

Question 4

Cardiogenic/hypovolemic shock - what does the skin feel like?

Answer 4

Cold and clammy because catecholamines have vasoconstriction to redirect blood to vital organs

Question 5

What is the main factor controlling peripheral vascular resistance?

Answer 5

Radius of the vessel (to the 4th power)

Question 6

What happens to peripheral vascular resistance in septic shock?

Answer 6

Decreases because we have vasodilation - makes skin warm because of increased blood pressure

Question 7

What is cardiac output in septic shock vs. cardiogenic/hypovolemic shock?

Answer 7

Septic shock - increase because of vasodilation vs. cardiogenic/hypovolemic shock - decrease because of vasoconstriction

Question 8

Is mixed venous oxygen content lower in septic shock or cardiogenic/hypovolemic shock?

Answer 8

Cardiogenic/hypovolemic shock because cardiac output is decreased and peripheral resistance is increased so tissues have lots of time to extract oxygen from the blood (opposite in septic shock - high mixed venous oxygen content)

Question 9

Total peripheral resistance is determined mainly by which vessels?

Answer 9

Arterioles

Question 10

How do we differentiate cardiogenic vs. hypovolemic shock?

Answer 10

Pulmonary capillary wedge pressure = measure of end diastolic pressure in left ventricle

Cardiogenic - high vs. Hypovolemic - low

Question 11

Which organ suffers greatest from decrease in BP?

Answer 11

Kidney (medulla)

Question 12

What’s the most common cause of respiratory alkalosis?

Answer 12

Anxiety - hyperventilation

Question 13

Why do all pregnant women have a little bit of respiratory alkalosis?

Answer 13

Estrogen and progesterone overstimulate the respiratory center

Question 14

What are the acid-base disturbances in septic shock?

Answer 14

Respiratory alkalosis - from overstimulation of respiratory center by endotoxin

Metabolic acidosis - from anaerobic glycolysis (lactic acid build up)

Question 15

What are the acid-base disturbance caused by salicylate toxicity?

Answer 15

Respiratory alkalosis - from overstimulation of respiratory center

Metabolic acidosis - from build up of salicylic acid