Flow-directed pulmonary artery catheters are used as an invasive method to monitor hemodynamic status in critically ill patients and in diagnostic and therapeutic procedures in cardiology. Pulmonary artery (PA) catheters are also called Swan-Ganz catheters.
The placement of a pulmonary artery catheter is invasive. The insertion site of a PA catheter must be determined on an individual basis, because each potential site for insertion is associated with specific risks and benefits.
The potential sites for insertion of Swan-Ganz catheters include the internal jugular vein, the subclavian vein, the femoral vein and the right or left brachial veins.
The right internal jugular vein and left subclavian vein are often used because these veins provide the easiest passage of the Swan-Ganz catheter into the pulmonary artery. This is simply because of the curve of the catheter and the vein.
However, there are risks associated with both of these potential insertion sites. When using the internal jugular (IJ) vein, puncture of the carotid artery is relatively common and there is a risk of pneumothorax (air filling the pleural cavity from puncturing the lung).
There is an even higher risk of pneumothorax when using the subclavian vein to place a PA catheter. In addition, it is possible to puncture the subclavian artery. If the carotid artery is punctured when attempting an IJ line it is possible to apply direct pressure on the artery to stop the bleeding. However, it is difficult, if not impossible, to directly compress the subclavian artery given its deep internal location.
The femoral vein may be used to place a PA catheter. However, there is a higher risk of infection and a risk of deep vein thrombosis (DVT) formation as compared to the IJ and subclavian veins. Additionally, it may be more difficult to place the catheter and imaging with fluoroscopy may be required.
The right or left brachial veins are a safer option if the patient has a bleeding disorder or coagulopathy (difficulty clotting). This access may also be the easiest option in morbidly obese patients. However, placement of a PA catheter using brachial veins is more difficult and time consuming. Once the PA catheter is placed, its use is limited to a 72 hour duration because of the risk of infection and phlebitis (inflammation of the vein).
PA catheters are an invasive means to measure hemodynamic status and are associated with fairly significant risks. PA catheters should only be placed when there is a specific question regarding a patient’s hemodynamic status that cannot be answered by clinical or noninvasive means.