test 3

Question 1

What is one of the main uses for the intra-aortic balloon pump?

Answer 1

• cardoigenic shock

Question 2

Miocardial infarctions effect on the systolic phase

Answer 2

• a decrease in CO and SV -> hypotenstion -> decrease coronary perfusion pressure -> ischemia -> progressive myocardial dysfunction -> death
• a decrease in CO and SV -> decrease in systemic perfusion -> compensatory vasoconstriction (increase in afterload) -> progressive myocardial dysfunction -> death

Question 3

Miocardial infarctions effect on the diastolic phase

Answer 3

• an increase in left ventricular end diastolic pressure ending up in pulmonary congestion -> hypoxia -> ischemia -> progressive myocardial dysfunction -> death

Question 4

what is the intra-aortic balloon pump considered

Answer 4

• Cardiac ASSIST Device: Patient must be ejecting blood

- won’t keep a patient alive on its own

Question 5

intra-aortic balloon pump components

Answer 5

1) Gas cylinder (He)
2) Gas supply unit
3) Monitoring system
4) Control unit
- duel lumen = gas and blood compartment

Question 6

IABP Treatment for:

Answer 6

 Cardiogenic shock postmyocardial infarction - bridge to reperfusion therapies
 Acute myocardial ischemia / Unstable angina
 Acute cardiac defects - bridge to emergent surgery
 Bridge to transplant/assist device implant
 Perioperative support of high-risk cardiac and general surgical patients
 Weaning from CPB
 Stabilize high-risk patient for PTCA (balloon that clears out plaque from the coronaries), stent placement & angiography
 Pharmacologically intractable ventricular arrhythmias
 Septic Shock*

Question 7

Contraindications - Absolute

Answer 7

 Thoracic or abdominal aortic aneurysm
 Dissecting aortic aneurysm
 Severe aortic insufficiency - regurgitation
 Major coagulopathies (bleeding is major problem)
 Underlying brain death
 End-stage diseases
 Advanced or terminal neoplastic disease

Question 8

Contraindications - Relative (at the surgeon or caregivers choice)

Answer 8

 Severe aortic or femoral atherosclerosis

 Symptomatic peripheral vascular disease

Question 9

Intra-Aortic Balloon Insertion Sites

Answer 9

1) both right and left femoral artery (main insertion sites)
2) abdominal aorta
3) ascending or descending aorta (will have to leave chest open)
4) right subclavian

Question 10

how does the balloon inflate?

Answer 10

• Base to tip
• As balloon expands, it displaces the same amount of blood pushing it toward the tip.
• designed to be put in retrograde

Question 11

Percutaneous Insertion Seldinger Technique: Step 1

Answer 11

• after palpating the artery, the physician inserts an 18 gauge angiographic needle through the skin and into the artery

Question 12

Percutaneous Insertion Seldinger Technique: Step 2

Answer 12

• The physician removes the stylet from the angiographic needle, and inserts the guidewire through the needle and into the artery.
• The guidewire is advanced up into the descending aorta so the tip of the wire is above the bifurcation of the aorta

Question 13

Percutaneous Insertion Seldinger Technique: Step 3

Answer 13

• The physician removes the angiographic needle from the artery, and then placing a dilator on the guidwire, advances the dilator into the artery.
• The dilator is removed and replaced with the sheath-dilator assembly

Question 14

Percutaneous Insertion Seldinger Technique: Step 4

Answer 14

• The dilator portion of the dilator-sheath assembly is removed.
• Physician removes the central lumen stylet from the balloon, places the balloon catheter over the guidewire, then advances the balloon catheter through the sheath and into the artery.
• The balloon is then advanced into the proper position within the descending aorta
• Use TEE to make sure the tip of the balloon is right where you want it

Question 15

Arterial Cut-Down (Surgical)

Answer 15

• done in the femoral artery
• make incision and expose femoral artery
• make incision in it
• insert the balloon
• get it into the right position
• put a flexible graft onto the outside of the vessel and secure that down to prevent any bleeding

Question 16

Benefits of doing a surgical insertion

Answer 16

• Direct visualization
• Less vessel trauma
• Less catheter kinking
• Applicable for patients with peripheral vascular disease

Question 17

Risks of doing a surgical insertion

Answer 17

• Bleeding
• Thromboembolism
• Infection
• Increased insertion time
• Requires surgical removal

Question 18

Benefits of doing a percutaneous insertion

Answer 18

• Increased speed of insertion
• Performed throughout hospital
• Less bleeding
• Decreased incidence of distal thromboembolism
• Decreased risk of infection

Question 19

Risks of doing a percutaneous insertion

Answer 19

• Lack of vessel visualization
• Potential increased vessel trauma
• Increased chance of thromboembolism during removal
• Increased chance for dissection
• Not applicable for patients with peripheral vascular disease

Question 20

Proper Balloon Position

Answer 20

• the tip of the balloon should be at the junction of the aortic arch and the descending aorta
• about 1 to 2 cm below the left subclavian artery
• on X-ray
  - top of the balloon at the center of the second intercostal space
  - bottom of the balloon should be at the L1 vertibrae

Question 21

What is possible if the balloon is too low

Answer 21

• could occlude their renal ateries resulting in no renal blood flow which leads to renal failure

Question 22

How occlusive is the balloon in the aorta

Answer 22

• want it to be 80 to 90% of the diameter of the patients aorta
• not completely occlusive or could result in:
  - damage to aorta
  - block blood flow
  - platelet activation

Question 23

Goals of Balloon Pump Treatment

Answer 23

- increase supply and decrease demand
 Increase cardiac output
 Decrease myocardial work
 Decrease myocardial oxygen demand
 Decrease myocardial ischemia
- all done by volume displacement

Question 24

Inflate the balloon during

Answer 24

• diastole

Question 25

Deflate the balloon during

Answer 25

- systole

Question 26

Balloon Counterpulsation

Answer 26

- Generation of a balloon pulse that is synchronized to occur opposite the cardiac cycle.  Heart creates pulse during systole  Balloon creates pulse during diastole

Question 27

Goal of Counterpulsation

Answer 27

 Inflate balloon during diastole |  Deflate balloon before ventricular ejection (during isovolumetric contraction => right at the peak of R wave)

Question 28

Purpose of Trigger Logic

Answer 28

- Synchronizes the patient’s cardiac cycle of systole and diastole with the balloon pump’s cycle of deflation and inflation

Question 29

Trigger Logic

Answer 29

 Tells pump console when the patient’s heart has entered systole  Provides starting point for timing logic  Provides mechanism to ensure that balloon will not be inflated during systole  Triggering information HAS to be provided by the patient

Question 30

Triggering Options

Answer 30

 Electrocardiogram  Senses the rate at which the ECG voltage changes  Usually upstroke of R wave satisfies the criteria  What if the patient has a pacemaker => pacer spikes will do the trick  Pressure (if patient doesn't have and EKG like during CPR)  Senses the rate at which the arterial blood pressure changes  Internal (patient doesn't have either)

Question 31

Optimize ECG Triggering

Answer 31

 Maximize amplitude of R wave  Do not need (or want) a diagnostic ECG  Minimize amplitude of other waves  Avoid electrical interference

Question 32

Establishing Optimal ECG Trigger

Answer 32

 Skin preparation  Use silver-silver chloride electrodes  Consider lead placement

Question 33

Where to connect the IABP to get an EKG reading

Answer 33

- add to anesthesias monitor using a slave cord to trigger off of that

Question 34

Where to connect the IABP to get an EKG reading when the case is over

Answer 34

- put the 4 to 5 leads on and switch the balloon back over

Question 35

Optimize Pressure Triggering

Answer 35

 You can measure patients aortic pressure from the tip of the balloon (internal lumen)  Prevent catheter whip  Prevent over damping of waveform

Question 36

Fiber-optic (at the tip) IAB catheters

Answer 36

 Automatic in vivo calibration  Every 2 hours  Instantaneous signal transmission  Consistent and accurate arterial blood pressure waveform

Question 37

Purpose of Timing Logic

Answer 37

- Used to set the precise inflation and deflation points

Question 38

Timing Logic

Answer 38

 Separate controls for setting inflation and deflation  Act as timers  Affected by trigger source  Set inflation point first, then set deflation point  Changing inflation point will affect timing of deflation point  Proper timing can ONLY be verified by looking at the patient’s arterial waveform (have to compare it to the patients native arterial waveform)

Question 39

Effects of Balloon Inflation on the Proximal Compartment

Answer 39

 Increased perfusion pressure at the coronary ostia  Increased diastolic pressure in the aortic root  Coronary blood flow may increase  Collateral coronary circulation may open  Increased perfusion to head vessels

Question 40

Effects of Balloon Inflation on the Distal Compartment

Answer 40

 Increased peripheral runoff  Increased systemic perfusion  Magnitude of effect depends on position of balloon tip (toward head or toward legs)

Question 41

Effects of Balloon Deflation

Answer 41

 Rapid reduction in aortic pressure  10 to 15 mmHg decrease in pressure (afterload) - decreases pressure in the aorta so the aortic valve opens earlier

Question 42

Isovolumic Contraction

Answer 42

- using the IABP reduces this phase - This is where 90% of the oxygen consumption occurs - therefore reduces the oxygen consumption

Question 43

Effects of Decreased Afterload

Answer 43

 Cardiac work is decreased  Maximum tension developed by ventricle reduced  Myocardial oxygen consumption is decreased  Balance between myocardial oxygen supply and demand may be restored

Question 44

Factors that effect the demand

Answer 44

- DECREASING THE LV WALL TENSION - myocardial contractility will increase the demand - heart rate will increase the demand - the heart is ejecting faster and less time for diastole so the filling is reduced - we reduce the afterload so decreasing LV wall tenstion by using the IABP

Question 45

Factors that effect the supply

Answer 45

- INCREASING DIASTOLIC BLOOD PRESSURE AND DECREASING LV INTRAMURAL PRESSURE - myocardial O2 uptake - LV intramural pressure - when intramural pressure is greater you have less blood flow down the coronaries and putting a greater pressure on the coronaries - it is reduced by using the IABP - coronary flow - Diastolic BP - we are augmenting with the IABP (when it deflates we are raising the diastolic P)

Question 46

Endocardial viability ratio

Answer 46

= Diastolic pressure time index (supply) / time tension index (area under LV systolic curve or demand) - the goal is to increase the ratio - anything less than 0.7 is severe myocardial ischemia