The intra-aortic balloon pump is a support device that works on the principle of counterpulsation. It inflates during diastole thereby augmenting diastolic aortic pressure, improving coronary blood flow, and systemic perfusion. And deflates during systole, thereby reducing LV afterload.
Demonstrating the insertion of balloon pump today, will be myself and Dr.Ganesh Gajanan, Interventional Cardiology Fellow at the University of Nebraska Medical Center. Before performing the procedure, have the patient lay flat in the supine position and prepare and drape the patient in the usual sterile fashion with a plan to access the femoral artery. Next, use a 50 milliliter syringe to apply vacuum to the one-way valve at the catheter hub of the IABP catheter.
When the balloon has been completely deflated remove the stylet in the catheter and manually flush the inner lumen with three to five milliliters of saline. For IABP insertion use the Seldinger technique to obtain femoral arterial access. Using ultrasound guided vascular access improves the first pass success and minimizes vascular complications.
Insert a micropuncture needle at a 45 degree angle. When blood return is observed insert the introducer wire. Briefly insert the micropuncture sheath before exchanging for a larger IABP sheath.
Using short strokes, advance the IABP catheter through the sheath until the tip of the balloon is situated distal to the left subclavian artery takeoff. Using the carina of the trachea as a landmark and ensuring that the proximal end of the catheter is above the renal arteries. Then secure the catheter in place.
When the catheter has been secured remove the guide wire. Flush the inner lumen with three to five milliliters of saline, and attach a piece of standard arterial pressure monitoring tubing to the catheter hub. Remove the one way valve from the catheter and use the provided extension catheter to attach the catheter hub to the console.
Turn the IABP on and open the gas tank. Connect the ECG cable and the fiber optic or pressure cable to the console. Press the start key on the console to automatically purge, fill, and calibrate the balloon.
Select an appropriate ECG lead and trigger and set the inflation and deflation timing. Select an appropriate operation mode according to the clinical scenario and select a trigger source. The IABP uses a trigger to identify the beginning of the next cardiac cycle, and deflates the balloon when it recognizes a trigger event.
Set a one to two frequency and observe the pressure changes on the IABP console to confirm that the assisted systolic pressure is lower than the unassisted one, that there is a decrease in the assisted and diastolic pressure, and that the diastolic augmentation is above the systolic pressure. If an optimal IABP support has been obtained set an appropriate IABP frequency and confirm that the IABP timing is appropriate. Then set the catheter to deliver a continuous flush of saline at a rate of three milliliters per hour through the inner lumen.
Start the patient on systemic anticoagulation with unfractioned heparin or bivalirudin to reduce the risk of arterial thromboembolism, provided that there are no clinical contraindications to anticoagulation. After checking the distal pulses of the patient check the insertion site for signs of bleeding or hematoma and monitor the urine output. Recheck the balloon position to confirm that the balloon lies above the level of the renal arteries.
If there is blood in the IABP tubing, balloon rupture is suspected. Then obtain a chest x-ray to verify optimal positioning of the device and change the sterile dressing to reduce the chances of infection daily. Stop systemic anti-coagulation prior to removing the IABP and set the IABP to one to one.
After checking baseline distal perfusion using doppler and the activated clotting time, remove the sutures and press stop on the IABP console. Pull the IABP until resistance is met against the sheath. Hold the sheath in the IABP as a unit and apply manual pressure over the femoral artery for 20 to 30 minutes or until the bleeding stops.
Reassess the distal pulses with doppler. In this table, the hemodynamic changes caused by IABP can be observed. As illustrated optimal IABP support can be confirmed by the presence of an assisted systolic pressure that is lower than the unassisted pressure, a decrease in the assisted and diastolic pressure, and a diastolic augmentation that is above the systolic pressure.
There are a few important things to remember when inserting a balloon pump. Make sure that the balloon pump is inserted into the sheath as quickly as possible. The balloon tends to expand very rapidly once it's out of the plastic protector wrapping.
The balloon pump can be inserted either by back loading with the wire or by wiring into the vasculature first and then advancing the balloon over the wire. Finally, make sure that the tip of the balloon is situated just to the left subclavian artery take off and the the proximal end is above the renal arteries.
