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IABP (INTRA-AORTIC BALLOON PUMP (IABP) COUNTERPULSATION)

Introduction:

Aspiration of arterial blood during systole with reinfusion during diastole decreased

cardiac work without compromising coronary perfusion Harkin-1960s Intraascular olume displacement with late! balloons - early 1960s

"he Intra-aortic balloon pump #IA$%& is a mechanical deice that is used to decrease

myocardial o!ygen demand' left ventriculr !"!tolic #or$% left ventriculr end-di!tolic

&re!!ure% nd #ll ten!ion while at the same time increasing cardiac output( $y increasingcardiac output it also increases coronary blood flow and therefore myocardial o!ygen deliery(

T'e &rir" ol! of IABP tretent re to incre!e "ocrdil o*"en !u&&l" nd

decre!e "ocrdil o*"en dend+ Secondr"% i&roveent of crdic out&ut (CO)%

e,ection frction (E)% n incre!e of coronr" &erfu!ion &re!!ure% !"!teic &erfu!ion nd

decre!e of 'ert rte% !"!teic v!culr re!i!tnce occur+

Princi&le! of t'e IABP

Counter&ul!tion: A techni)ue that synchroni*es the e!ternal pumping of blood with the

heart+s cycle to assist the circulation and decreasing the work of the heart(

,ounterpulsation pumps when the heart is resting to increase blood flow and o!ygen to

the heart( ,ounterpulsation stops pumping when the heart is working to decrease the

heart+s workload and lessen o!ygen demand(

%repared by (./"HI/',2

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INSERTION TEC.NI/UES

3ince 1949' a percutaneous placement of the IA$ ia the femoral artery using a modified

Seldiner techni)ue allows an easy and rapid insertion in the ma5ority of situations( Afterpuncture of the femoral artery a -shaped guide wire is inserted to the leel of the aortic

arch and then the needle is remoed( "he arterial puncture side is enlarged with thesuccessie placement of an to 10'78r dilatorsheath combination( :nly the dilator needs

to be remoed( ,ontinuing' the balloon is threaded oer the guide wire into the descending aorta 5ust

below the left subclaian artery( "he sheath is gently pulled back to connect with the

leak-proof cuff on the balloon hub' ideally so that the entire sheath is out of the arterial

lumen to minimi*e risk of ischemic complications to the distal e!tremity( ;ecentlysheathless insertion kits are aailable( ;emoal of a percutaneously placed IA$ may

either be ia surgical remoal or closed techni)ue( "here are alternatie routes for

balloon insertion( In patients with e!tremely seere peripheral ascular disease or inpediatric patients the ascending aorta or the aortic arch may be entered for balloon

insertion( :ther routes of access include subclaian' a!illary or iliac arteries

Correct &lceent of Intr-Aortic Blloon

It i! in!erted into t'e de!cendin ort vi t'e feorl rter" eit'er &ercutneou!l"

or 0" !uricl cut-do#n+

It should be positioned so that the tip is appro!imately 1 to < cm below the origin of the

left subclaian artery and aboe the renal arteries(

After correct placement of the IA$ in the descending aorta with it=s tip at the distal aortic

arch #below the origin of the left subclaian artery& the balloon is connected to a drie console(

"he console itself consists of a pressuri*ed gas reseroir' a monitor for 2,> and pressure wae


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recording' ad5ustments for inflationdeflation timing' triggering selection switches and battery

back-up power sources( "he gases used for inflation are either helium or carbon dio!ide( "he

adantage of helium is its lower density and therefore a better rapid diffusion coefficient(?hereas carbon dio!ide has an increased solubility in blood and thereby reduces the potential

conse)uences of gas emboli*ation following a balloon rupture(

Correct &o!itionin i! criticl in order to void 0loc$in off t'e !u0clvin or renl

rterie!+ So &lceent if confired 0" flouro!co&" or C'e!t 1-r"+ T'e ti& !'ould 0e vi!i0le

0et#een 2ndnd 3rdinterco!tl !&ce+

T0le 4: .eod"nic effect! of IABP T'er&"

ctor! Affectin 5i!tolic Auenttion

1( %atient Hemodynamics

Heart ;ate' 3troke olume' .ean Arterial %ressure' 3ystem ascular ;esistance

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INLATION AN5 5ELATION O BALLOON

It then rapidly inflates immediately following aortic ale closure to augment #"o make

#something already deeloped or well under way& greater' as in si*e' e!tent& diastolic

coronary perfusion pressure( ?hen inflated' the balloon blocks 7-90D of the aorta(,omplete occlusion would damage the walls of the aorta' red blood cells' and platelets(

"he balloon rapidly deflates 5ust before entricular systole to reduce the impedance #A

measure of the total opposition to current flow in an alternating current circuit& to left

entricular e5ection

Inflation and deflation are synchroni*ed to the patientsE cardiac cycle( Inflation at the

onset of diastole results in pro!imal and distal displacement of blood olume in the aorta(Ceflation occurs 5ust prior to the onset of systole(

Infltion of IABP:

"he balloon is inflated during diastole in sync with the closure of the aortic ale(


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"he blood in the aortic arch aboe the leel of the balloon is pushed backward proiding

increased coronary artery blood flow and increased myocardial o!ygen supply(

Infltion of IABP Cu!e!

o Increased coronary perfusion pressureo Increased systemic perfusion pressure

o Increased :< supply to both the coronary and peripheral tissue

o Increased baroreceptor response

o Cecreased sympathetic stimulation causing decreased Heart ;ate' decreased

3ystemic ascular ;esistance' and increased eft entricular function

5efltion O IABP

"he balloon rapidly deflates 5ust before entricular systole to reduce eft entricular

work helps to decrease afterload( "he space where the balloon was inflated creates an empty space where the blood doesn+t

hae to flow against any resistance(

5efltion cu!e!

o Ceflation creates a Fpotential spaceF in the aorta' reducing aortic olume and

pressure

o Afterload reduction and therefore a reduction in myocardial o!ygen consumption

#.:

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3ome medications #i(e( asoconstrictors' asodilators&

Afterlod i! t'e re!i!tnce t't t'e 'ert u!t overcoe in order to e,ect t'e 0lood volue

fro t'e left ventricle+ Afterlod cn 0e ffected 0":

Aortic alular stenosis

Arterial asoconstrictors and asodilators

Hypertension

%eripheral arterial constriction

.EMO56NAMICS

Blloon Infltion : .eod"nic!

Inflation of the balloon occurs at the onset of diastole( At the beginning of diastole'

ma!imum aortic blood olume is aailable for displacement because the left entricle has

5ust finished contracting and is beginning to rela!' the aortic ale is closed' and the

blood has not had an opportunity to flow systemically(

"he pressure wae that is created by inflation forces blood superiorly into the coronaryarteries("his helps perfuse the heart(

$lood is also forced inferiorly increasing perfusion to distal organs #brain' kidneys'

tissues' etc(&

Benefits of Accurately timed Inflation :

- ,oronary artery blood flow and pressure are increased(( Increased perfusion may increase the

o!ygen deliered to the myocardium(

- ,oronary collateral circulation is potentially increased from the increased ,%% #coronaryperfusion pressure&

-Increased diastolic pressure also increases the perfusion to distal organs and tissues(

-3ystemic perfusion pressure is increased(

Blloon 5efltion : .eod"nic!

"he balloon remains inflated throughout diastole(

At the onset of systole' the left entricle has to generate a pressure greater than the

A2C% #Aortic 2nd Ciastolic %ressure& to achiee e5ection( $ut the sudden loss of aorticpressure caused by the deflation of the balloon reduces this afterload(

"he left entricle does not hae to generate as much pressure to achiee e5ection since the

blood has been forced from the aorta(


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"his lower e5ection pressure reduces the amount of work the heart has to do resulting in

lower myocardial o!ygen demand(

Benefit! of ccurtel" tied 5efltion:

"he pressure that the must generate is less throughout the systolic phase( "herefore'

afterload is reduced which decreases myocardial o!ygen demands( ;educed afterload allows the to empty more effectiely so 3 #stroke olume& is

increased(

2nhanced forward ,:(

Also decreases the amount of blood shunted from left to right in cases of intraentricularseptal defects(

P'"!ioloicl Effect! of IABP

ARTERIAL 7A8EORM 8ARIATIONS 5URIN9 IABP T.ERAP6


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Sc'etic re&re!enttion of coronr" 0lood flo#% ortic nd left ventriculr &re!!ure #ve

for #it' #it'out IABP+ (Effect! on 5PTI nd TTI + Blloon infltion durin di!toleuent! di!tolic &re!!ure nd incre!e! coronr" &erfu!ion &re!!ure ! #ell !

i&rovin t'e reltion!'i& 0et#een "ocrdil o*"en !u&&l" nd dend (5PTI:TTI

rtio)

CONTROL O T.E IABP

TRI99ERIN9

"o achiee optimal effect of counterpulsation' inflation and deflation need to be correctly

timed to the patientEs cardiac cycle( "his is accomplished by either using the patientEs 2,>

signal' the patientEs arterial waeform or an intrinsic pump rate( "he most common method oftriggering the IA$ is from the ; wae of the patientEs 2,> signal( .ainly balloon inflation is set

automatically to start in the middle of the " wae and to deflate prior to the ending ;3

comple!( "achyarrhythmias' cardiac pacemaker function and poor 2,> signals may causedifficulties in obtaining synchroni*ation when the 2,> mode is used( In such cases the arterial

waeform for triggering may be used(

TIMIN9 nd 7EANIN9

It is important that the inflation of the IA$ occurs at the beginning of diastole' noted on thedicrotic notch on the arterial waeform( Ceflation of the balloon should occur immediately prior

to the arterial upstroke( $alloon synchroni*ation starts usually at a beat ratio of 1J

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TIMIN9 ERRORS

4+ Early Inflation - Inflation of the IA$ prior to aortic ale closure

7vefor C'rcteri!tic! :

Inflation of IA$ prior to dicrotic notch(

Ciastolic augmentation encroaches onto systole' #may be unable to distinguish&(

P'"!ioloic effect!:

%otential premature closure of the aortic ale(


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%otential increase in 2C and 2C%(

Increased left entricular wall stress or afterload(

Aortic regurgitation(

Increased .0< demand(

2. Late Inflation - Inflation of the IA$ markedly after closure of the aortic ale

7vefor C'rcteri!tic!:

Inflation of IA$ after the dicrotic notch(

Absence of sharp (

P'"!ioloic Effect!:

- 3ub-optimal coronary artery perfusion

- 3ub-optimal diastolic augmentation

3. Early Deflation - %remature deflation of the IA$ during the diastolic phase

7vefor C'rcteri!tic!

Ceflation of IA$ is seen as a sharp drop following diastolic augmentation(

3ub-optimal diastolic augmentation(

Assisted aortic end diastolic pressure may be KL the unassisted aortic end diastolicpressure(

Assisted systolic pressure may rise(


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P'"!ioloic Effect!:

- 3ub-optimal coronary perfusion

- %otential for retrograde coronary blood flow

- Angina may occur as a result of retrograde coronary blood flow

- 3ub-optimal afterload reduction B Increased .0< demand(

4. Late Deflation- ate deflation of the IA$ during the diastolic phase(

7vefor C'rcteri!tic!:

Assisted aortic end diastolic pressure may be e)ual to the unassisted aortic end diastolic

pressure(

;ate of rise of assisted systole is prolonged(

Ciastolic augmentation may appear widened(

P'"!ioloic Effect!:

Afterload reduction is essentially absent(

Increased .0< consumption due to the left entricle e5ecting against a greater resistance

IA$ may impede left entricular e5ection and increase the afterload

IN5ICATIONS


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1( ;efractory Mnstable Angina

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3eere calcific aorta-iliac disease or peripheral ascular disease

3heathless insertion with seere obesity' scarring of the groin' or other contraindications

to percutaneous insertion

;enal failure and bowel ischemia

eurologic complications including paraplegia

Heparin induced thrombocytopenia

Side Effect! nd Co&liction! of IABP T'er&"

. Lim! Isc"emia:

2. E#cessi$e !leeding from insertion site:

3. Balloon lea% & IAB ru'ture:

4. Infection

(. Aortic &erfortion ndor di!!ection

) .*om'artment syndromes may de$elo' after IAB remo$ed.(

CONTRACTILIT6

Q ,ontractility refers to the elocity and igor of contraction during systole(


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