Exam #2

Question 1

Know the formula for oxygen content

Answer 1

O2 content = (gm Hbg)(1.34 ml O2/gm Hbg)(% sat) + 0.003(pO2) = ml O2/Dl

UNITS = ml O2/Dl

Question 2

hemoglobin formula

Answer 2

hematocrit/3

Question 2

what are the 4 types of hypoxia

Answer 2

Hypoxemic hypoxia ( decreased Pa02)

Anemic hypoxia (decreased Hgb)

Circulatory hypoxia (decreased lung or cardiac function)

Histotoxic hypoxia (decreased cell utilization)

dealing with most likely the first THREE

Question 3

assessing oxygenator performance

Answer 3

if flowing at 100%, PO2 should be at 500

if PO2 is lower

if FiO2 is at 50%, it should be 250

figure out oxygen requirement increased

Question 4

calculation of oxygen delivery DO2

Answer 4

DO2 = CaO2 x Q, where q is blood flow (either cardiac output or arterial pump flow)

calculate on arterial side

CaO2 = oxygen content

NOTE: If L/min is the unit of measure for flow, a factor of 10 will be used to convert everything to “mls
DO2 = CaO2 x Q x 10
DO2 = 12.27 ml O2% x 4.8 L/min x 10
DO2 = 588.9 ml O2/min

For example, if DO2 is indexed, Qindex = 4.8/2.02 = 2.38 L/min/m2
Therefore, DO2 index = 12.27 x 2.38 x 10 = 292 ml O2/min/m2

Question 5

oxygen consumption

Answer 5

VO2= Qt(CaO2-CvO2) x 10

calculate venous side

Question 6

Oxygen transfer

Answer 6

.(Art sat-Ven sat) x1.34 x Hgb x Q(cc)/100
Not the best formula as factors influence saturations.

DO2/VO2 ratio

ONLY NEED TO KNOW THIS DOWN BELOW

–> KNOW the difference arterial and venous sat = 25% –> NORMAL SATURATION
100%-75% = 25%
between 25%-35%

Question 7

The cardiovascular system can be sub divided into 3 different catagories: KNOW this

Answer 7

1. Cor (Heart)
2. Conduits(Vessels)
3. Content (Blood)

Question 8

4 subunits of CONDUITS

Answer 8

1. DISTRIBUTION VESSELS (AORTA,PULM ART,LARGE ART)
2. RESISTANCE VESSELS (ARTERIOLOES)
3. EXCHANGE VESSELS (MET ARTERIOLES,CAPILLARIES) highest control of resistance is arterioles
4. CAPACITANCE VESSELS ( VENULES,GREAT VEINS,IVC,SVC). –> holds majority of your blood

Question 9

BODY CONSISTS OF 2 MAJOR CAPILLARY BEDS

Answer 9

1) PULMONARY CIRCULATION 30-35%
2) SYSTEMIC CIRCULATION 65-70%

Question 10

what percentage do the Capacitance vessels contain of the systemic blood volume?

Answer 10

65%-70%

Question 11

Shunting

Answer 11

5-10% of the blood flow returns to the left heart without returning to the pulmonary vasculature.
Bronchial Artery –> drain into pulmonary veins
Plueral arteries –> drain into pulmonary veins
Thesbesian vessels –> drain into all hambers

Shunting is: Perfusion in excess of Ventilation or Ventilation in excess of Perfusion

Question 12

lactic acid

Answer 12

Lactic acid –> anerobic
Metabolized in the liver and excreted out by the kidneys
Important molecule that gets excreted is HYDROGEN H+

Question 13

carbonic anhydrase

Answer 13

CO2 binds to water –> carbonic anyhydrase (enzyme) –> creates Bicarb and Hydrogen

renal tubular cells produce carbonic anhydrase

Question 14

urine output

Answer 14

want 1cc/kg per hour

Question 15

renal mechanism

Answer 15

H+ is buffered

if you have poor kidney function, you might have a difficult time regulating pH on bypass

Question 16

three important ccemical buffers

Answer 16

Protein buffer system –> Hemoglobin is the BIGGEST buffer in the body

phosphate buffer system
bicarbonate buffer system

Question 17

number one factor of metabolic acidosis

Answer 17

LACTATE

Question 18

decrease in anion gap maybe due to…

Answer 18

hypoproteinemia –> decrease in albumin

Question 19

Hypoalbuminemia

Answer 19

decreased anion gap

decrease in negative charge

Question 20

Finding Cardiac index

Answer 20

Cardiac index = Q/BSA

Question 21

nil composition same osmotic pressure as plasma

Answer 21

35% remains in the vasculature

Question 22

crystalloid compared to blood

Answer 22

want it to be same osmotic pressure as plasma
same electrolytes and water

ph same as plasma 7.4

permeable

Question 23

major priming solutions

Answer 23

plasma Lyte A

isolyte
normosol
lactated ringers

Question 24

colloids

Answer 24

oncotic force
keeps fluid to stay in the vasculature

Question 25

albumin

Question 26

RAP

Answer 26

retrograde autologous prime

Question 27

CPR

Answer 27

clear prime replace

can also be known as VAP

Question 28

hemodilution

Answer 28

POSITIVES:
DECREASE VISCOSITY
DECREASE SHEAR STRESS
INCREASES REGIONAL AND MICROCIRCULATORY BLOOD FLOW
DECREASES EFFECTS OF DRUGS DUE TO PROTIEN BINDING
NEGATIVES:
DECREASES O2 CARRYING CAPACITY
HYPOTENSION
ISCHEMIC ORGAN INJURY
WHATS ACCEPTABLE???
DELIVERY MEETS CONSUMPTION 2X