Known as the pulmonary artery catheter or the right heart catheter, the Swan Ganz thermodiultion catheter is a useful tool that provides vital information about the functioning of the heart in patients who are critically ill. Basically, it is a soft catheter with a tip fitted with an inflatable balloon that is used to monitor blood pressure in the pulmonary artery. Initially used to manage acute myocardial infraction in patients, the Swan Ganz catheter procedure is today widely used for the diagnosis, management, assessment of response, and monitoring of patients who are suffering from any type of cardiac disease.
The Swan Ganz catheter is a long tube with several openings or ports; it is inserted into a large vein in the neck by a surgeon who then guides it to the pulmonary artery on the right side of the heart. This helps doctors and nurses keep an eye on the pressure in the heart and the blood vessels going to the lungs, as it is connected to a monitor. In addition, the Swan Ganz catheter insertion also serves to take blood samples and to introduce medicines and IV fluids into the body. The blood samples from the veins are assessed for oxygen transport, consumption, and utilization. Also read more on paracentesis procedure.
Swan Ganz catheter pressures monitored include the direct measurement of the pressures in the right artery, right ventricle, and the pulmonary artery. Left arterial pressure is measured indirectly by measuring the pulmonary artery occlusion pressure by using the balloon at the tip of the catheter. In order to obtain accurate information that can facilitate diagnosis, the pulmonary artery catheter must be zeroed and referenced. Continuous and accurate monitoring of pulmonary artery pressure is vital as the therapy will depend on the values obtained. Hemodynamic data, along with additional information obtained from the Swan Ganz catheter values, may provide clues for the diagnosis, guide management, and help determine the prognosis.
Apart from pressure measurements, the pulmonary artery catheter also helps to get a quantitative measurement of cardiac output through the indicator thermodilution method or the Fick method. Apart from inserting the Swan Ganz catheter, interpretation of the pressure curves requires far more skill and training from the physicians, if the hemodynamic data derived is to be useful in treating the patient. There is also the view that the Swan Ganz catheter should be used only in cases where hemodynamic data cannot be obtained from non-invasive procedures or clinical evaluation.