Ch 14 IABP Flashcards
What are the 8 indications for IABP?
- Unstable angina
- Acute MI
- Cardiogenic Shock
- Mechanical Complications following MI
- Adjunct to Percutaneous Transluminal Coronary Angioplasty (PTCA)
- Adjunct to cardiac cath
- BTT
- Operative (pre, intra, and post) support
What are 5 contraindications to IABP?
ABSOLUTE:
- Thoracic / Abdominal Ao Aneurysm
- Occluded Aorta
RELATIVE:
- AI
- Severe PVD
- Disease not amenable to definitive therapy
What are 7 complications to IABP ?
- Limb Ischemia
- Thromboembolism
- Aortic Dissection
- Vascular Injury (laceration, false aneurysm, hematoma)
- Infection
- Balloon Rupture
- Thrombocytopenia
What medication must be given when initiating IABP therapy?
Heparin 5,000 units IV
Before you remove the IAB from the holder, what kind of preparation must be done to the IAB?
Negative pressure applied to the IAB with the one-way valve in place.
Inflation of the IAB causes what?
Increase in diastolic pressure due to the displacement of volume.
When the IAB inflates, it causes an increase in diastolic pressure, what is the benefit of this?
Increased coronary perfusion
If the IAB inflates too EARLY, what can we assume?
Causes the following:
1.) Resistance to systolic ejection > Reduction of LV
emptying > ↓ Cardiac Output
2.) Greatly increased afterload.
3.) Premature closure of the Aortic Valve
4.) Increased cardiac workload and oxygen consumption
** DETRIMENTAL**
If the IAB inflates too LATE, what can we assume?
Inflation would be late in the diastolic portion of the cardiac cycle, therefore; this limits
- Amount of augmentation that can be achieved
- Reduces coronary perfusion
In relation to the IAB waveform, what are the following waveform characteristics from left to right at 1:1 ?
- ) Upward wave #1
- ) Upward wave #2
- ) Downward wave #3
- ) Upward wave #4
- ) Unassisted Systole
- ) Assisted diastolic augmentation
- ) Assisted AEDP
- ) Assisted Systole
When the IAB deflates just prior to systole, there is a sudden decrease of pressure within the Aorta; this causes what?
1.) ↓ AEDP > ↓ Afterload = ↓Myocardial work, ↓ O2 consumption, ↑ Cardiac Output
What does conventional timing refer to ?
Based on the duration of inflation during diastole, R to R interval on the EKG or peak to peak interval of the arterial pressure wave.
Real timing of the IAB is based on?
Balloon deflation corresponding to systole.
The delay between the QRS complex and the Aortic valve opening is called what?
Pre-ejection period (PEP)
[Relatively constant]
The period of time between the opening and closing of the Aortic valve is referred to as?
Ejection Time (ET)
[Relatively constant]
PEP + ET + ( ) = Contraction
Ventricular Diastole, the remaining period where changes with irregular rates and rhythms occur.
- ) How long does it take for the counterpulsation event to reach the subclavian artery?
- ) How long does it take for the counterpulsation event to reach the Aortic Root?
- ) Approximately, what is the total delay ?
4.) Therefore, how do you compensate for this delay when timing inflation of the IABP?
- ) 25 msec
- ) 25 msec
- ) One small block (40 msec) on standard EKG paper at a speed of 25 mm/sec.
4.) Time inflation 1 block left of the dicrotic notch.
How do you determine deflation of the IABP?
1.) Evaluate the Assisted AEDP, it should be less than
the Unassisted AEDP.
2.) Make sure the Assisted Systole following augmentation is less than
Deflation, when using conventional timing is set to occur at ?
The End if Diastole during isovolumetric contraction
REAL TIMING DEFLATION occurs at what point?
At each QRS complex
EARLY Deflation results in ?
- ) Lesser level Reduction in AEDP
- ) Decreased Afterload Reduction
- ) Retrograde flow in the Aorta > Angina
LATE Deflation results in ?
Causes the IAB to remain inflated into the next systolic ejection, this causes the heart to work much harder.
- ) ↑ Myocardial Work
- ) ↑ MvO2
- ) ↓ Cardiac Output
DETRIMENTAL
What is the correct order in FRQUENCY RATIO WEANING?
1:1, 1:2, 1:3,
What is VOLUME WEANING?
Volume decreased by a small portion 20-25% of the total volume. If tolerated, additional volume may be reduced NOT to go below 20% of its total volume.
