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The Pulmonary Artery Catheter Kit:
The sterile kit containing the pulmonary artery catheter contains fewer parts than the kit for the central venous catheter.
- Multi-hub pulmonary artery catheter : This long catheter has 4 separate hubs on one end. The large hub is the themistor connector, and is used for thermodilution to assess cardiac output (more on that later.) There is the distal lumen hub, which connects to a distal outlet on the tip of the catheter, and a proximal hub, which
 connects to a more proximal hub on the catheter. The fourth hub is a balloon inflation valve which is used to inflate a small balloon on the end of the catheter in order to attain pulmonary capillary wedge pressure (more on that later as well!) If you look closely, the length of the catheter has markings every 10cm along its length to help the operator determine the position of the catheter within the vasculature and heart.
- Syringe: This syringe is used to fill the balloon of the catheter with air, and is limited to only 1.5ml; this prevents the balloon from becoming overinflated.
- Plastic Sheath : This long sheath is to cover the part of the pulmonary artery
 catheter which sticks out from the central venous catheter port, and to keep the PAC sterile so it may be advanced or withdrawn as needed without exposing the patient to increased risk of infection.
The Procedure:
As with placing the central venous catheter, placing a pulmonary artery catheter (or “PAC”) is done in a sterile fashion. Usually, the pulmonary artery catheter is placed immediately following central venous catheter cannulation and securing. The PAC is threaded through a port of the central venous introducer, so of course the central venous catheter first must be in the vein, and should be tested for proper placement before insertion of the PAC can begin.
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After the central venous introducer is in place and has been secured with sterile dressing, an assistant will open the pulmonary artery kit in a sterile fashion, being careful not to contaminate any of the contents.
- Remove the pulmonary artery catheter from the kit, and check the proximal and distal ports for patency by flushing them with sterile saline. An assistant should hook up the ports to the transducer, and make sure that the readings are accurate as the catheter is being manipulated.
- Place the sterile plastic sleeve over the catheter, and pass the end with the hubs to the assistant to hook up to the transducer. The transducer will measure the pressures from the catheter, which will then be shown on the monitor during surgery. The catheter should pick up wave tracings as it is manipulated.
- Remove the syringe from the kit, and with this syringe, test the balloon by filling it with 1.5ml of air. Watch as the balloon should inflate and deflate easily.
- The distal end of the PAC is then inserted into the central venous sheath hub, and is threaded down the internal jugular, into the superior vena cava. Once in the SVC, the balloon is inflated and the catheter is advanced through the right atrium, past the tricuspid valve into the right ventricle, quickly through the right ventricle (to minimize occurrence of arrhythmias) and past the pulmonary valve into the pulmonary artery. Once in the pulmonary artery, the catheter should be carefully advanced until it wedges. At this point the balloon can be deflated, and pulmonary artery tracings should reappear. If the balloon wedges before maximal re-inflation, then the catheter is “overwedged” and should be pulled back slightly until it wedges only with maximal inflation (this helps prevent pulmonary artery rupture- a very bad thing.).
- During this threading process, keep track of how far the catheter tip has traveled into the patient; this is made easier by noting the markings along the length of the
 catheter. In the kits used at UVA, one dash signifies 10cm, two dashes indicates 20cm, and so forth. A broad black mark defines the 50 cm point. There are general guidelines for how far the catheter must be advanced to reach a certain area:
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The waveforms and pressure readings seen on the monitor while the catheter is being advanced will provide more definitive information on the position of the catheter in the vasculature (a working example of this can be seen on the movie clip). Although this will be explained in detail on another page, an overview of the characteristics of each position are as follows:
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Right atrium: a, c and v waves, 0-8mmHg
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Right ventricle: increase in systolic pressure, 15-30/0 mmHg
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Pulmonary artery: increase in diastolic pressure, 15-30/10mmHg
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Pulmonary artery wedge: 5-15mmHg
At this point, with the catheter in the correct position, the balloon can be deflated, and the catheter secured in place in the central venous catheter hub. The sterile plastic sleeve should cover the PAC entirely until the point it disappears into the hub; this way, if the PAC needs to be advanced or withdrawn slightly during the case, the risk of infection is kept to a minimum. Correct catheter placement may be confirmed with a chest x-ray.
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