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Description

• Polyethylene balloon filled with helium: 2-50cc in size
• Placed in the descending aorta just distal to the subclavian artery

1. Inflates in diastole: improves coronary blood flow
2. Deflates in systole: reducing afterload

• Improves oxygen supply:demand ratio
• Cardiac output may be increased by 40%

Indications

1. Weaning from bypass
2. Peri-operative ischaemia
3. Post-op poor cardiac output refractory to inotrope support

Contraindications

1. Aortic regurgitation
2. Aortic dissection
3. Caution in peripheral vascular disease

Principles

1. Reduces impedance of heart by rapid deflation prior to ventricular systole
2. Increases diastolic coronary perfusoin by rapid inflation just after aortic valve closure

Insertion

1. Prepare the pack / balloon
   • 2 Sterile drapes
   • Prep
   • Sterile gown and gloves
   • Suture
   • 11 blade
   • 10ml of 1% lignocaine if the patient is awake
   • Balloon pump, balloon: 40cc for men, 30cc for women
   • Giving set with saline
2. Palpate the femoral pulse (mid femoral point between ASIS and PS)
3. Prep and drape
4. Check that the wire runs smoothly through the wire holder
5. Draw back 60mls on the syringe connected to the IABP to ensure that the balloon is collapsed
6. Remove the IABP from packaging and withdraw the wire from the sidearm
7. Aspirate the femoral artery (saline syringe advanced into artery)
8. Remove syringe, advance the guidewire
9. Make a nick in the skin with the 11 blade over the wire and advance the dilator into the femoral artery
10. Measure the IABP so that the tip is at the 3rd rib space; advance the proximal end of the guard so that it is at the groin
11. Withdraw the dilator, press over the wire to prevent bleeding
12. Insert the IABP over the wire into the femoral artery up to the proximal guard
13. Remove the guide wire
14. Take the manometry line, flush and connect to the IABP via a three-way-tap; aspirate blood; when the system is free from air connect it to the IABP console - an arterial trace should be visible
15. Remove the yellow internal marker and attach the air port to the side arm and hand out to the balloon console
16. Fix in place
17. Obtain a CXR to check the position (should be just distal to the subclavian artery - to not impair blood flow to the ITA); TOE

Intra-aortic balloon pump timing

1. ECG
   
   
   
   
   • Provided input from skin leads
   • Inflation set for the peak of the T-wave
   • Deflation set just before or on the R-wave
2. Arterial waveform
   
   
   
   • Inflation occurs on dichrotic notch
   • Deflation just before the onset of the aortic upstroke

Troubleshooting the balloon

1. Inability to Balloon
   
   
   

   Challenge	Physiology / Features	Remedy
   Unipolar atrial pacing	Produces large atrial spike mis-interpreted as a QRS complex Leads to inappropriate inflation / deflation	Use bipolar pacing
   Rapid rates	Balloon unable to inflate / deflate fast enough	Use 1:2 augmentation
   Arrythmias	Atrial / ventricular ectopics disrupt normal inflation	Treat causes
   Volume loss from balloon	Due to a leak in the system at connectors / balloon
   Balloon rupture	Signified when blood is in the balloon tubing	Remove immediately before thrombus occurs within the balloon leading to balloon entrapment

2. Vascular / Haematological complications
   
   
   

   Challenge	Physiology / Features	Remedy
   Catastrophic injury	Aortic dissection Rupture of iliac artery Rupture of aorta Haematoma Embolisation
   Distal ischaemia	5-10% of patients Common in patients with small BSA Thrombosis at insertion site or distal thromboembolism can occur	Heparin maintaing APTTR 1.5-2 times control (if balloon remains in for > a few days) Assess distal pulses Remove sheath Remove balloon if stable; consider femoral exploration Remove balloon and replace in contralateral leg if IABP dependent
   Thrombocytopenia	Mechanical inflation/deflation destroys platelets	Daily check of platelet count

   
   

Weaning the IABP

1. Satisfactory Cardiac output
   • Indication for IABP passed
   • Inotropes weaned to min-moderate dose
2. Decrease inflation ratio from 1:1 to 1:2 for 2-4hours; then to 1:3 for 1-2 hours (ratio should be 1:2 to prevent thrombus formation)
3. Stop heparin 1 hour before removal
4. Check coagulation and platelets (>50) before removal - prevents haematoma/false aneurysm
5. Turn down the augmentation
6. Put balloon on assist-standby mode: observe trace to make sure there is no augmentation
7. Turn off the balloon pump
8. Cut off sutures
9. Pull balloon out; wait 3 seconds to flush out clot
10. Apply pressure for 20-30 minutes at site of arterial puncture
11. Monitor next 24/h for haematoma formation and distal limb ischaemia