PERFUSION TECHNIQUE

Question 1

The term “perfusion” is derived from the
French verb ‘perfuse’ meaning?

Answer 1

to ‘pour over or through’

Question 2

They employ artificial blood pumps to propel open-heart surgery patients’ blood through their body tissue, replacing the function of the heart while the cardiac surgeon operates.

Answer 2

Perfusionists

Question 3

a skilled, allied health professional, trained and educated specifically as a memberof an open- heart, surgical team responsible for the selection, setup, and operation of a mechanical device commonly referred to as the heart- lungmachine

Answer 3

Perfusionists

Question 4

include various modalities of temporary mechanical cardiopulmonary assistance used to support patients with severe heart and/or lung failure which is unresponsive to optimal conventional care

Answer 4

Extracorporeal membrane oxygenation (ECMO) and Extracorporeal Life Support
(ECLS)

Question 5

What is the main objective of ECMO and ECLS?

Answer 5

provide systemic perfusion and gas
exchange allowing the heart and/or lungs to rest and recover to different
modality of support or to transplantation

Question 6

development of a roller pump in the 1930’s led to the first successful extracorporeal assist in 1953

Answer 6

Dr. John Gibbon

Question 7

revolutionized the artificial lung with
the development of synthesis of silicone rubber

Answer 7

Kammermeyer

Question 8

developed an approach to continuously titrate coagulation with Heparin

Answer 8

Bartlett and Drinker

Question 9

reported the first successful cardiac ECMO run of 36 hours in a 2 year old infant with cardiac failure

Answer 9

Bartlett, Gazzaniga et al.

Question 10

provides a bloodless field for cardiac surgery

Answer 10

Cardiopulmonary bypass (CPB)

Question 11

What is the mechanism of CPB?

Answer 11

It incorporates an extracorporeal circuit to
provide physiological support in which venous blood is drainedto a reservoir, oxygenated and sent back to the body using a pump.

Question 12

True or False: Team effort between surgeon, perfusionist and anaesthesiologist is paramount for the successful use of CPB

Answer 12

True

Question 13

True or False: ECMO circuit includes pumps, cannulae, tubing, reservoir, oxygenator, heat exchanger and arterial line filter

Answer 13

False - CPB

Question 14

What are the 2 types of pumps?

Answer 14

1. Roller pump
2. Centrifugal pump

Question 15

Roller pump includes ____
positioned on a rotating arm, which
compress a length of tubing to produce
forward flow

Answer 15

2 rollers

Question 16

In roller pump, the compression of tubing produces forward flow, what can this action produce?

Answer 16

haemolysis and tubing debris

Question 17

True or false: Use of roller pumps for longer procedure is discouraged

Answer 17

True

Question 18

Centrifugal pump consists of _____ cones within housing

Answer 18

Impellers/stacked

Question 19

What happens to a centrifugal pump when rotated rapidly?

Answer 19

Negative pressure is created at one inlet, positive on the other = propelling blood forward

Question 20

True or false: Centrifugal pumps can’t improve platelet preservation, renal function and neurological outcomes in longer cases.

Answer 20

False: It can

Question 21

Which pump is afterload independent, no flowmeter required, and increase blood trauma and tubing debris?

Answer 21

Roller pump

Question 22

Which pump is retrograde flow possible, expensive but for long-term use, portable, and has no disruption?

Answer 22

Centrifugal pump

Question 23

Which pump has no backflow occurs, cheap, short-term use, bulky, and has circuit disruption?

Answer 23

Roller pump

Question 24

Which pump is afterload depndent,needs flowmeter, has descreased blood trauma and tubing debris?

Answer 24

Centrifugal pump

Question 25

Which pump has lesser risk of air embolism and more priming volume?

Answer 25

Centrifugal pump

Question 26

Which pump has greater risk of air embolism and less priming volume?

Answer 26

Roller pump

Question 27

connect the patient to the circuit and hence to the CPB machine. They are made of **polyvinylchloride (PVC)** and are wire reinforced to prevent obstruction due to kinking

Answer 27

Cannulae

Question 28

are used during most open-heart surgeries, where two cannulae are inserted into the superior and inferior vena cava and joined by a **Y-piece**

Answer 28

Venous cannulae/single-stage cannulae

Question 29

used for most closed-heart procedures, where a single cannula is inserted into the right atrium. **Drainage** occurs through gravity. Vacuum applied to the reservoir allows the use of smaller cannulae and tubing, thus decreasing the circuit volume.

Answer 29

Dual-stage cannulae

Question 30

are largely of historical interest in the era of membrane oxygenators.

Answer 30

Bubble oxygenators

Question 31

consist of hollow microporous polypropylene fibres (**100–200 μm internal diameter**)

Answer 31

Oxygenator

Question 32

These are generally made of PVC, due to PVC's durability and acceptable haemolysis rate. Plasticisers like di(2-ethylhexyl)phthalate which are added to impart flexibility are potentially toxic and shown to leach from the tubing

Answer 32

Tubing

Question 33

Newer plasticisers such as _______ have less leaching and are under investigation.

Answer 33

dioctyl adipate

Question 34

True or false: Closed reservoirs have a limited volume capacity, but offer a smaller area of blood contact with artificial surfaces

Answer 34

True

Question 35

They collect the blood drained from the ____. Open reservoirs are more commonly used. They allow passive removal of entrained venous air along with the option of applying vacuum to assist drainage.

Answer 35

heart

Question 36

a method of myocardial protection where the heart is perfused with a solution to cause electromechanical arrest which reduces myocardial oxygen consumption.

Answer 36

Cardioplegia system

Question 37

True or false: Cardioplegia can be crystalloid (cold) or blood-based (warm or cold); can be given continuously or intermittently.

Answer 37

True

Question 38

solutions are commonly used for cardioplegia system?

Answer 38

Potassium based solution

Question 39

Blood cardioplegia is a combination of **oxygenated blood and crystalloid in a ratio ranging from**

Answer 39

1:! to 8:1

Question 40

True or False: The deairing of CPB circuit is done by priming solutions, consisting of a mixture of crystalloids and colloids. P

Answer 40

True

Question 41

True or false: riming causes haemodilution which improves flows during hypothermia.

Answer 41

True

Question 42

Heparin ____ units/ml is added to the prime.

Answer 42

3–4 units/ml

Question 43

During anterial cannulation, systolic pressure should be __ to __ mm Hg to reduce the risk of aortic dissection.

Answer 43

90-100

Question 44

The aortic cannulation is done first to provide volume resuscitation in case of hypotension associated witvenous cannulation.

Answer 44

Initiation

Question 45

is a point-of-care test used to assess the adequacy of heparinisation. Normal ACT ranges from

Answer 45

80 to 120 s

Question 46

ACT must be monitored every?

Answer 46

30-40 mins

Question 47

Perfusion pressure is used as a surrogate marker of organ perfusion and should be maintained between

Answer 47

50 and 70 mmHg

Question 48

it evoked potentials and transcranial Doppler can be used to assess the adequacy of cerebral blood

Answer 48

Cerebral oximetry

Question 49

True or false: blood level in the reservoir should be monitored to prevent air embolism. Central venous pressure (CVP) should be low. High CVP indicates a good venous return.

Answer 49

Both are true

Question 50

Glucose is maintained between mg/dL. Anaesthesia can be maintained by inhalational route or total intravenous anaesthesia can be given.

Answer 50

120 and 180 mg/dl

Question 51

is frequently used during CPB for its presumed organ protective effects

Answer 51

Hypothermia

Question 52

is a point-of-care test used to assess the adequacy of heparinisation. Normal ACT ranges from 80 to 120 s

Answer 52

Activated clotting time (ACT)

Question 53

true or false: Blood viscosity decreases with hypothermia and allows maintenance of a higher perfusion pressure despite haemodilution. However, hypothermia reversibly inhibits the clotting factors and platelets.

Answer 53

1st false - increases dpt 2nd true

Question 54

CPB can be used for the induction of total body hypothermia, a state in which the body can be maintained for up to __ minutes without perfusion (blood flow). If blood flow is stopped at normal body temperature, permanent brain damage normally occurs in __ to __ minutes — death may follow shortly afterward.

Answer 54

45 mins; 3-4 mins

Question 55

used after completion of the surgical repair before protamine administration, with blood removed from the arterial line and returned to the venous line after passing through the haemofilter.

Answer 55

Modified ultrafiltration (MUF)

Question 56

removes inflammatory mediators and excess fluid thereby producing haemoconcentration.

Answer 56

Ultrafiltration

Question 57

the process where extracorporeal support is gradually withdrawn as the heart takes over the circulation

Answer 57

Weaning

Question 58

Nasopharyngeal temperature should not exceed __, although authors accept temperature range of 35.5°C–36.5°C.

Answer 58

37°C

Question 59

can be associated with bleeding, cannula malposition causing selective cerebral perfusion, plaque dislodgement and dissection.

Answer 59

Arterial cannulation - mechanical cannulation

Question 60

can be associated with bleeding, cannula malposition/air lock causing an inadequate return, leading to cerebral and splanchnic congestion

Answer 60

Venous cannulation - mechanical cannulation

Question 61

What are the systemic complications of CPB?

Answer 61

- Acute **respiratory** distress syndrome - Qualitative and quantitative **platelet dysfunction** - Inflammatory response and hypotension can cause acute **kidney** injury (AKI) - Risk factors are prolonged bypass time, **sepsis and diabetes**. - The spectrum of **cerebral injury** ranges from cognitive dysfunction to stroke.

Question 62

T or F: Subclinical myocardial injury can occur due to cross clamping of the aorta in spite of cardioplegia.

Answer 62

True