2. • Brief history
• Structure
• functions & physiological effects
• indications & contraindications
• Device operation – Balloon insertion & device set up, timing, trigger,
weaning
• Special circumstances
• Literature
3. Brief History
• 1961 – preliminary studies using latex balloon in animals -
Moulopoulous et al
• 1963 – concept of ext counterpulsation explained by Dennis et al
• 1967 – first successful clinical treatment in cardiogenic shock
• 1970s – series of successful treatment of patients in cardiogenic
shock by Krantrowitz et al
• by 1976 - > 5000 patients in USA with post MI cardiogenic shock were
offered IABP
4. Structure
The console consists of :
• Monitor system – for acquisition of ECG or iBP input
• Control unit - processes the input & times the valve unit
• Valve unit – delivers gas to the balloon
• Gas source
5. Balloon
• Made of polyurethane membrane ( 1 mm thick)
• Actual inflatable segment is round 28 cms long, and insertable length is
about 70 cms.
• Appropriate size selection based on patient’s height.
• Balloon length : estimated by keeping distal tip at : sternal angle – umbilicus -
proximal tip at femoral artery
• When inflated , it occupies 80-90% of aortic diameter
• Optimal position : just (1cm) distal to origin of left subclavian artery & above the
bifurcation of renal arteries
Patient
Height ( cm )
Balloon
Volume ( ml )
1. < 152 cm 25
2. 152 – 163 cm 35
3. 164 -183 cm 40
4. > 183 cm 50
7. Driving Gas
• Helium
• CO2 – used earlier
Hagen Poisseuille law :
Helium has least viscosity maximum flow
8. Functions
• BALLOON INFLATION – immediately after Aortic valve closure
-- corresponds to middle of T wave
• BALLOON DEFLATION – during isovol. contraction & systole
-- deflation to peak of R wave
9. What does that do on Aortic waveform ?
• slope of augmented diastolic wave form is
straight and parallel to the systolic upstroke
• the augmented DP should exceed non-
augmented SP
• the EDP at balloon deflation is lower than
preceding unassisted EDP by 15 mmHg
• the SP following a cycle of balloon inflation
should be lower than the previous
unassisted SP by about 5 mmHg
10. Physiological effects
Inflation-occurs immediately after aortic valve closure
1. Increase in pressure in descending aorta during diastole.
2. Increase in coronary and peripheral perfusion pressure - coronary flow
increases upto 5 -15 %, cerebral flow can increase upto 50 %.
3. Increases O2 supply.
4. Increases baroreceptor response.
5. Decreases sympathetic response.
11. • Deflation occurs during isovolumetric contraction and balloon
remains deflated during complete systole.
1. Decreases afterload
2. Improved O2 consumption
3. Increases ejection fraction and forward flow
12. Indications
• Cardiogenic shock
• Failure to wean from CPB
• Procedural support during coronary intervention
• Bridge to cardiac trasplant
13. Contraindications
• aortic regurgitation
• aortic dissection
• severe aortoiliac or peripheral vascular disease
• aneurysm or other anatomical disease of aorta
• prosthetic aortic tree grafts
• local sepsis
• lack of experience with management
• severe coagulopathy
• not effective in a setting of a CI of < 1.2 and tachyarrhythmias
• Mitral SAM with dynamic outflow tract obstruction
14. Device Operation : Insertion & Setup
• Insertion Techniques :
1. Direct Access
• Ascending aorta or aortic arch in patients with PVD or paediatric
patients with small vasculature.
• Insertion requires median sternotomy
• Removal requires re-exploration
15. 2. Percutaneous insertion with seldinger technique
• Pass balloon through sheath over guidewire and insert estimated distance –
measure from sternal angle to umbilicus then to femoral artery.
• Must be inserted to at least the level of the manufacturer’s mark (usually double
line) to ensure that entire balloon has emerged from sheath
• Balloon should be positioned so that the tip is about 1 cm distal to the origin of the
left subclavian artery
• watch for loss of left radial pulse (too high)
16. CONFIRMATION OF POSITION
• Arterial and balloon waveforms on console monitor
• Radiologically – fluroscopy or CXR
• CXR - in left 2nd ICS just above left bronchus
• With TOE - just distal to origin of left subclavian artery.
18. Setting Up The Machine To Commence Pumping
• Connect to mains
• Check that the helium tank is open
• Ensure ECG and arterial trace can be obtained on monitor either direct or slave cables
from the monitor
• Augmentation is to be kept at full and frequency of heart beat to balloon pumping is set
at 1:1
• Timing of balloon cycling is synchronized
• All the cables and catheters are connected to console.
• Once connected , hold IAB fill button for 2 seconds.
19. 2. Timing
• Refers to inflation and deflation of IAB in relation to cardiac cycle.
• Inflation occurs just after diacrotic notch and sustained through
diastole
• Deflation occurs during iso-volumetric contraction phase of systole
and sustained all through systole.
20. 3. Trigger
• Triggers are physiological variables used to enable correct timing
1. ECG -best available trigger (inflation corresponds to middle of T wave
and deflation to peak of R wave)
2. Arterial pressure waveforms- (inflation corresponds to diacrotic
notch and deflation to a point just before the upstroke)
21. Triggering modes-
• Ecg Pattern: the height, width and slope of a positively or negatively
deflected QRS complex are analysed by the IABP machine. This is the
preset (default) trigger mode
• Ecg Peak: the height and slope of a positively or negatively deflected
QRS complex are analysed by the IABP machine. This is the trigger
mode of choice in wide complex rhythms
• A. Fib: the QRS complex is analysed in the same manner as in the
peak mode. This is the trigger mode of choice in varying R-R intervals
as in atrial fibrillation.
22. • V Pace: Ventricular signal is used as the trigger signal. This is the trigger mode of
choice in 100% ventricular or AV paced rhythms
• A Pace: Atrial is used as the trigger signal. This is the trigger mode of choice in 100%
atrial paced rhythms
• Arterial Pressure: Systolic upstroke of the arterial pressure waveform as the trigger
signal. This is the trigger mode of choice where ECG signals are distorted or
unavailable ( eg , during CPR )
• Internal: The balloon inflates and deflates at a preset rate regardless of the patient's
cardiac activity. This mode is used in situations where there is no cardiac output or ECG
is unavailable.
23. Augmentation
• This is the ability of balloon to be fully expanded and contain the full amount of
helium for catheter
• During normal pumping balloon should be kept on full augmentation (full lights
on the monitor),to prevent blood clots and thrombosis formation
• Augmentation to be done slowly to unwrap the balloon, fast augmentation may
cause balloon to unwrap incompletely.
24. Monitoring Patient On IABP
• Haemodynamic Monitoring
• Assessment Of Waveforms
• Peripheries Examination (Radial And Dorsalis Pedis Pulse, Colour,
Warmth)
• Urine Output
• Platelet Counts
• ACT (180-200 Seconds)
• APTT (1.5-2 Times The Control Value)
26. Weaning Off IABP
• With judicious use of inotropes and vasodilators
• Balloon augmentation reduced in stepwise manner from 1:1 to 1:2 to 1:3
• Continuous monitoring of haemodynamic parameters, neurological status,
cardiac output, mixed venous oxygen saturation
• Anticoagulation should be ceased 4-6 hours before removing the balloon.
27. Use In Special Circumstances
1. Cardiac arrest
• The IAB can be used in normal mode of either ecg or pressure trigger as
the system will synchronize to the rate and rhythm of chest compression.
• Internal trigger can be used sometimes which provides fixed rate of 80
beats /min
• Or it can be left on standby mode but not more than 30 minutes in situ
2. Defibrillation-
• The current IABP is completely isolated from the patient and it is safe to
have patient defibrillated with IABP in situ. Ensure that everybody is away
from IABP machine.
28. 3. Atrial fibrillation
• IAB should be triggered from the ecg and deflation point should be
moved to the extreme right.
• This will cause automatic deflation on R wave , maximizing the time
the IAB catheter is inflated with irregular heart rate and arterial
pressure
4.Pacemaker
• Either V/AV trigger or A trigger can be used.
29. Problems associated with timing
1. Early inflation
2. late inflation
3. early deflation
4. late deflation
30. 1. Early Inflation
Waveform Characteristics :
• Inflation prior to dicrotic notch
• Diastolic augmentation encroaches onto systole
Effect :
• Premature closure of AoV
• Increased LVEDV & LVEDP
• Incresed LV stress or afterload
• Ao regurgitation
• Incresed MVO2 demand
32. 3. Early deflation
Waveform Characteristics :
• deflation seen as a sharp drop after dias. augmentation
• assisted Ao EDP may be equal or > unassisted EDP
• Assisted sys pressure may rise
• Effects :
• Suboptimal coronary perfusion
• potential for retrograde coronary & carotid blood flow
• suboptimal afterload reduction
• increased oxygen demand
33. 4. Late deflation
Waveform characteristics :
• Assisted Ao EDP may be equal to unassisted Ao EDP
• Rate of rise of assisted systole is prolonged
• Dias Augmentation is widened
Effects :
• Absent afterload reduction
• inc oxygen demand
34. Complications related to IABP use
VASCULAR
• Arterial injury –
perforation, dissection
• Aortic perforation
• Aortic dissection
• Femoral artery thrombosis
• Peripheral embolization
• Inadvertant femoral vein
cannulation
• Femoral pseudoaneurysm
• Limb ischemia
• Visceral ischemia
• Compartment syndrome
MISCELLANEOUS
Hemolysis
Thrombocytopenia
Infection
claudication
hemorrhage
SC necrosis
Aggravation of dynamic outflow
tract obstruction
BALLOON RELATED
Perforation
Tear during insertion
Incorrect positioning
gas embolization
inadvertent removal
35. Literature related to IABP in shock
• IABP-SHOCK II trial (2012) - no 30-day mortality benefit from IABP insertion for
cardiogenic shock following MI when early revascularisation was planned.
• Ranucci et al (2013) found that in patients undergoing nonemergent coronary
operations, with a stable hemodynamic profile and a left ventricular ejection
fraction <35%, the pre-incision insertion of intra-aortic balloon pump does not
result in a better outcome.
• Sjauw et al (2009) systematic review found that only low-quality observational
studies support IABP use post-STEMI for thrombolysis, not for PCI.
• TACTICS trial (2005) was a small trial that showed no mortality benefit for IABP
in addition to thrombolysis for STEMI
• Despite the paucity of evidence for cardiogenic shock complicating MI, use of
IABP for mechanical assistance had a class IC recommendation in the current
ESC guidelines and a class IB recommendation in the ACC/AHA Guidelines.
