Mechanical Circulatory Devices Flashcards
With use of an IABP, when does the cardiac cycle supply decrease?
The Intra-Aortic Balloon Pump decreases cardiac supply during balloon deflation.
** E = E **
What does the IAMP function as?
The Intra-Aortic Balloon Pump functions as a volume displacement device.
What are the three triggers to initiate the IABP balloon inflation cycle?
The three triggers to initiate the IABP balloon inflation cycle are:
- “R” wave
- Arterial Waveform
- Pacing Spikes
What trigger does the IABP machine primarily utilize to initiate a correctly timed balloon inflation?
The “R” wave is used as the primary trigger used by the Intra-Aortic Balloon Pump machine in order to correctly time the balloon inflation.
Your patient has an IABP. Which of the following statements is true?
A. You would expect that this patient would have a decreased coronary blood flow because of the IABP.
B. Renal blood flow is reduced in patients with an IABP
C. The IABP will decrease the patients afterload
D. The IABP will increase this patient’s heart rate
C. The IABP will decrease the patients afterload
What does the formula (SV x HR) ÷ BSA give you?
Cardiac Index = [(SV x HR) ÷ 1000] ÷ BSA
After completing the initial limb pulses check, how often should the subsequent checks for limb pulses be conducted?
2 Hours
After the initial 30 minute check after the Intra-Aortic Balloon Pump insertion, subsequent checks for limb pulses must be conducted at least every 2 hours.
What does the dicrotic notch signify?
The dicrotic notch signifies closure of the aortic valve.
Which of the following equations is true regarding cardiac output?
A. Cardiac output = End diastolic pressure - systolic pressure
B. Cardiac output = Stroke Volume x Heart Rate
C. Cardiac output = (Stroke Volume x Heart Rate) ÷ BSA
4. Cardiac output = Systemic Vascular Resistance - peripheral vascular resistance
B. Cardiac output = Stroke Volume x Heart Rate
If the machine fails and the balloon becomes immobile, it must be inflated by hand every ______ minutes.
A. 1 - 5 minutes
B. 3 - 5 minutes
C. 5 - 10 minutes
D. 10 - 15 minutes
C. 5 - 10 minutes
What is the calculation for MAP?
Mean Arterial Pressure:
MAP = (DBP x 2) + SBP ÷ 3
What are the five major stages of the cardiac cycle?
The five major stages of the cardiac cycle are:
- Late Diastole (ventricular filling)
- Atrial Systole
- Isovolumetric Ventricular Contraction
- Ventricular Ejection (systole)
- Isovolumetric Ventricular Relaxation
What is the Fick Principle?
The Fick Principle assumes that the rate at which oxygen is consumed is a function of the rule of blood flow and the rate of oxygen picked up by the red blood cells.
You are transporting a patient with a VAD. As you are auscultating heart tones, you note that the VAD is making a knocking sound. Which of the following should you suspect?
A. The pump has failed the VAD
B. The patient is hypotensive or the VAD is in overdrive (suckdown)
C. The patient’s VAD is having electrical inference with something nearby
D. The VAD has a valve that is sticking
B. The patient is hypotensive or the VAD is in overdrive (suckdown)
What should the provider do every 5 - 10 mins in the event the IABP machine fails?
The provider should manually inflate and deflate the intra-aortic balloon with 40 - 60 mL of air/helium every 5 - 10 mins.
You observe what appears to be rust in the IABP tubing Which of the following should you expect?
A. Mechanical problems with the machine
B. Blood in the tubing
C. Infiltration of helium into the balloon
D. Use of an expired tubing set
B. Blood in the tubing
A patient with a VAD can be in a lethal arrhythmia and still be hemodynamically stable.
A. True
B. False
A. True
What is Isovolumetric Ventricular Contraction?
Isovolumetric Ventricular Contraction is an event occurring in early systole during which the ventricles contract with no corresponding volume change.
** all heart valves are closed **
If the IABP machine fails, what should the provider do?
The provider should manually inflate and deflate the intra-aortic balloon with 40 - 60 mL of air/helium every 5 - 10 mins.
In the presence of minimal supply and increasing demand, what harmful mechanism occurs to the myocardium?
As coronary perfusion requirements increase, cardiac ischemia increases.
** as this cycle increases, the damage increases **
Which of the following is the EKG trigger used to determine IABP inflation?
A. Diastolic notch
B. QRS complex
C. “P” Wave
D. “R” Wave
D. “R” Wave
What complication does an aortic valve insufficiency present with IABP application?
The driving systemic pressure is derived from the pressure generated via Intra-Aortic Balloon Pump inflation. If aortic valve insufficiency is present, pressure is lost via aortic valve regurgitation, backing up into the left ventricle and decreasing IABP effectiveness.
Does SVR mirror MAP or is it inverse?
Systemic Vascular resistance follows Mean Arterial Pressure.
** If one is high, the other is high **
Coronary blood flow increases during systole.
A. True
B. False
B. False
What effect on SVR does vasodilation have?
Vasodilation decreases System Vascular Resistance.
What is AEDP?
Aortic End-Diastolic Pressure (AEDP)
The pressure that the Left Ventricle (LV) must overcome in order to push volume out through the aortic valve and into systemic circulation.
** If AEDP is 80 mmHg, the LV must be able to pump at 81 ≥ in order to overcome the pressure difference **
When correctly placed, the IABP will occlude _______% of the aorta.
80 - 90%
When correctly placed, the IABP will occlude 80 - 90% of the aorta.
The __________ assumes that the rate at which oxygen is consumed is a function of the rule of blood flow and the rate of oxygen picked up by the red blood cells.
The Fick Principle assumes that the rate at which oxygen is consumed is a function of the rule of blood flow and the rate of oxygen picked up by the red blood cells.
What is Isovolumetric Ventricular Relaxation?
Isovolumetric Ventricular Relaxation is when ventricular pressure drops below the diastolic aortic pressure, the aortic and pulmonary valves close.
** This closure produces the S2 sound, marking the beginning of diastole **
How much air or helium should be in the syringe that is used to manually inflate the IABP balloon in the event of failure?
A. 1 mL
B. 10 mL
C. 60 mL
D. 100 mL
C. 60 mL
Which of the following is first-line treatment in an unstable VAD patient?
A. Increase the VAD’s speed
B. Externally pace the patient
C. Attempt volume resuscitation
D. Begin external chest compressions
C. Attempt volume resuscitation
What is the formula for SVR?
System Vascular Resistance:
SVR = (MAP - CVP) ÷ CO
What are the absolute contra indications for the IABP?
Absolute contraindications for the Intra-Aortic Balloon Pump:
- Aortic Valve Insufficiency
- Dissecting Aortic Aneurysm
When correctly placed, where does the cardiac supply IABP rest?
When correctly placed, the Intra-Aortic Balloon Pump will rest in the thoracic aorta, 1 - 2 centimeters below the subclavian artery.
What does myocardial oxygen consumption equate to?
Myocardial oxygen consumption (MVO2) equates to “supply and demand.”
In what way do overloaded ventricles result in a decreased supply of blood volume?
Ventricles result in a decreased supply of blood volume due to:
- Reduced contractility
- Reduced force of contractility
Which of the following patients would be a candidate for an IABP?
A. A patient with a congenital heart defect
B. A patient with unstable angina
C. A patient who is in hemorrhagic shock following a motor vehicle accident
D. A patient who has a history of SVT
B. A patient with unstable angina
_______ is the amount of blood pumped out of the left ventricle during each cycle.
A. Preload
B. Afterload
C. Ejection Fraction
D. Cardiac output
C. Ejection Fraction
How does hypertrophy affect cardiac output (pathological process)?
Stoke Volume (SV) is decreased as the myocardium grows enlarged
** thicker muscle walls does NOT equal bigger chambers **
What effect on SVR does vasoconstriction have?
Vasoconstriction increases System Vascular Resistance.
What is the maximum time frame for IABP immobility before consultation with medical control must be established?
30 mins is the maximum time frame for IABP immobility before consultation with medical control must be established.
What is the primary anatomical factor resulting in overall vascular resistance?
Arterioles are the primary anatomical factor resulting in overall vascular resistance.
Subsequent to IABP placement, how often must you check limb pulses?
Limb pulses must be checked 30 minutes after inserting an Intra-Aortic Balloon Pump.
With use of an IABP, when does the cardiac cycle supply increase?
The Intra-Aortic Balloon Pump increases cardiac supply during balloon inflation.
** I = I **
What should be suspected if “rust like flakes” are observed in the IABP tubing?
Tearing and/or bursting of the balloon should be suspected if “rust like flakes” are observed in the Intra-Aortic Balloon Pump tubing.
Which of the following patients would be a candidate for ECMO?
A. A patient with advanced multiple organ failure
B. A patient waiting for cardiac surgery that has a very low cardiac output with end-organ damage
C. A patient with septic shock who is unresponsive to other treatments.
D. A patient who is in severe metabolic acidosis with low cardiac output.
B. A patient waiting for cardiac surgery that has a very low cardiac output with end-organ damage
Which of the following indicates proper positioning of the IABP after insertion?
A. It should be placed 1 - 2 cm below the subclavian artery
B. It should be placed 1 - 2 cm above the subclavian artery
C. It should be placed 1 - c cm below the mesenteric artery
D. It should be placed 1 - c cm above the mesenteric artery
A. It should be placed 1 - 2 cm below the subclavian artery
When IABP timing is correct, when does the balloon deflate?
The Intra-Aortic Balloon Pump delates the balloon before the full onset of systole, if the timing is correct.
The loss of peripheral pulses in a patient with a VAD always signifies shock or cardiac arrest.
A. True
B. False
B. False
Which of the following represents an absolute contraindication for the IABP?
A. Cariogenic shock
B. Cardiac tamponade
C. Patients less than the age of 18
D. Severe aortic valve insufficiency
D. Severe aortic valve insufficiency
What is SVR?
Systemic Vascular Resistance (SVR) is the resistance to blood flow offered by all of the systemic vasculature EXCLUDING the pulmonary vasculature.
What does (HR x SV) ÷ 1000 =
(Heart Rate x Stroke Volume) ÷ 1000 =
Cardiac Output = (HR x SV) ÷ 1000
What is occurring hemodynamically upon IABP balloon inflation?
Blood is being pushed superiorly into the coronary arteries, increasing myocardial perfusion;
Blood is being pushed inferiorly into the distal organs.
In ECMO patients, there should be hourly assessments of neurovascular status in cannulated limbs and hourly assessment of urine output.
A. True
B. False
A. True
What are the FOUR measurements of cardiac output?
The FOUR measurements of cardiac output are:
- Cardiac Output (CO) : (SV x HR) ÷ 1000 = CO
- Cardiac Index (CI) : [(SV x HR) ÷ 1000] ÷ BSA
- Fick Principle
- Systemic Vascular Resistance (SVR)
In the event of IABP machine failure, how much air/helium should be used to manually inflate/deflate the intra-aortic balloon?
40 - 60 mL of air/helium every 5 - 10 mins.
__________ is an event occurring in early systole during which the ventricles contract with no corresponding volume change.
Isovolumetric Ventricular Contraction is an event occurring in early systole during which the ventricles contract with no corresponding volume change.
** all heart valves are closed **
The primary benefit of the IABP is that it corrects a supply verses demand mismatch in the heart.
A. True
B. False
A. True
Which of the following statements best describes the purpose of a ventricular assist device?
A. It is designed to replace all functions of the heart
B. It must be used in conjunction with a pacemaker
C. It only assists the right ventricle
D. It decreases the workload of the heart while maintaining adequate flow and blood pressure.
D. It decreases the workload of the heart while maintaining adequate flow and blood pressure.
