ECMO Physiology / Midterm Exam

Question 1

VA ECMO Cannulation ?

Answer 1

– Right Internal Jugular

– Right Common Carotid

Question 2

Goal or VA ECMO ?

Answer 2

80% of the cardiac output (80-100 ml/kg)

– Maintain pulsatile waveform (dampened)

Question 3

Optimal pulse pressure for VA ECMO ?

Answer 3

10 - 15 mmHg

Question 4

Anything that changes the volume status of the patient will change the ratio of pump to heart flow, such as ?

Answer 4

IV,
urine,
edema,
hemoconcentrator

Question 5

How can we calculate the preload to the pump?

Answer 5

CVP = Bladder Pressure

Question 6

On VA ECMO how can we monitor adequacy of perfusion?

Answer 6

SVO2

Question 7

Adding volume would increase pulse pressure, so therefore what can we expect of the PaO2 ?

Answer 7

Drop

Question 8

Removing volume would decrease our pulse pressure, so therefore what can we expect of the PaO2 ?

Answer 8

Increase

Question 9

Reducing pump flow would increase our pulse pressure, therefore what can we expect of the PaO2 ?

Answer 9

decrease

Question 10

Increasing pump flow would decrease our pulse pressure, therefore what can we expect of the PaO2 ?

Answer 10

Increase

Question 11

VV ECMO Cannulation ?

Answer 11

– Withdraw from RA

– Return to RA

Question 12

Goal of VV ECMO ?

Answer 12

• Increase blood O2 content
  prior to lungs.
• Dependent on heart for
  patient circulation

Question 13

What ECMO setup has has no effect on hemodynamics and the patient is dependent on heart for perfusion ?

Answer 13

VV ECMO

Wean from inotropes more slowly.

Question 14

SvO2 monitors recirculation with what ECMO circuit?

Answer 14

VV-ECMO

Question 15

Oxygen CAPACITY definition ?

Answer 15

The maximum amount of oxygen the blood is
capable of holding.
(Depends on Hct)
↓ Hct > ↓capacity > ↓ content > ↓ Delivery

Question 16

Oxygen CONTENT definition ?

Answer 16

The amount of oxygen actually in the blood.

CaO2

Question 17

Oxygen DELIVERY definition ?

Answer 17

The amount of oxygen provided to the cells.

Question 18

Oxygen CONSUMPTION definition ?

Answer 18

The amount of oxygen removed from the blood
by the cells.

SvO2

Question 19

What carries 98% of all

oxygen in the blood?

Answer 19

RBC

Question 20

Hct that would reflect an anemic patient?

Answer 20

Plasma 72%

Blood 28%

Question 21

Hct that would reflect an patient with Polycythemia?

Answer 21

Plasma 30%

Blood 70%

Question 22

Hct that would reflect a normal patient ?

Answer 22

Plasma 55%

Blood 45%

Question 23

Oxygen content CaO2 formula?

Answer 23

(Hb x 1.36 x SaO2)+(0.003 x PaO2)

Question 24

[Bound]

1 g Hb (3% Hct) =

Answer 24

[Dissolved]

450 mmHg

Question 25

Oxygen delivery DO2 formula =

Answer 25

CaO2 x CO

Question 26

C.O. formula =

Answer 26

HR X SV

Question 27

S.V. formula =

Answer 27

C.O. / HR

Question 28

Oxygen Consumption VO2 formula ?

Answer 28

(DaO2 - DvO2) x C.O.

Question 29

Normal newborn Arterial: SAT 100% PO2 = PCO2 =

Answer 29

``` PO2 = 100 PCO2 = 40 ```

Question 30

Normal newborn Venous: SAT 75% PO2 = PCO2 =

Answer 30

``` PO2 = 40 PCO2 = 45 ```

Question 31

Mixed Venous Oxygen Saturation SVO2 formula =

Answer 31

O2 delivered - O2 consumed

Question 32

what does a decrease in SVO2 represent ?

Answer 32

indicates that the body has called upon its last line of defense to preserve O2 balance and intervention may be appropriate.

Question 33

What are the 3 different blood samples to evaluate on VA ECMO ?

Answer 33

– Venous (pre oxygenator) – Post Oxygenator – Patient Arterial (mixed arterial)

Question 34

How would you evaluate Oxygenator function ?

Answer 34

Compare pre to post oxygenator blood gas

Question 35

How would you evaluate overall patient support ?

Answer 35

Compare patient and | venous blood gases

Question 36

How would you evaluate ECMO vs Patient contribution ?

Answer 36

– Compare Post and Patient blood gases. – Consider pump flow and arterial pulsatility

Question 37

Standing orders and parameters to maintain Hct ?

Answer 37

Maintain Hct > 40 % | – 10 ml/kg

Question 38

Standing orders and parameters to maintain Platelets ?

Answer 38

Maintain Platelets > 100 K – 1 unit for more than 20K below parameter – 1/2 unit is less than 20 K below parameter

Question 39

Standing orders and parameters to maintain fibrinogen ?

Answer 39

Maintain Fibrinogen >100 K | – 1 unit Cryoprecipitate (about 10 ml)

Question 40

Standing orders and parameters to maintain Flow ?

Answer 40

Give 10 ml/kg to maintain flow | – Fluid to be determined

Question 41

Unheparinized pts ACT normal values ?

Answer 41

90-120 sec

Question 42

ECMO average ACT range ?

Answer 42

160-220 sec | based on patient

Question 43

Uncomplicated TERM patient ECMO ACT range?

Answer 43

200-220 sec

Question 44

Uncomplicated PRETERM patient ECMO ACT range?

Answer 44

180-200 sec

Question 45

Surgical patient ECMO ACT range?

Answer 45

160-180 until hemostasis achieved, then increase parameter.

Question 46

Heparin dose to cannulate ? Heparin dose to initiate ?

Answer 46

- Bolus 100 u kg | - ACT > 200 sec

Question 47

Heparin management as ACT begins to drop ?

Answer 47

- Start GTT (100u/ml) - (monitor frequently) 50 u/kg/hr to start - Titrate GTT up and down to maintain ACT

Question 48

I'm having a hard time maintaining my ACT, what is the likely cause and what should I do about it?

Answer 48

- Platelets may decrease ACT, monitor frequently when administering Platelets. - Bolus 1/2 previous hours dose

Question 49

Diagnosing low bladder pressure on | (VA and V ECMO)?

Answer 49

• CVP