A pulmonary artery catheter (PAC), also known as a Swan-Ganz catheter or right heart catheter, is a balloon-tipped catheter that is inserted into a pulmonary artery in a procedure known as pulmonary artery catheterization or right heart catheterization. Pulmonary artery catheterization is a useful measure of the overall function of the heart particularly in those with complications from heart failure, heart attack, arrythmias or pulmonary embolism. It is also a good measure for those needing intravenous fluid therapy, for instance post heart surgery, shock, and severe burns. The procedure can also be used to measure pressures in the heart chambers. The pulmonary artery catheter allows direct, simultaneous measurement of pressures in the right atrium, right ventricle, pulmonary artery, and the filling pressure (pulmonary wedge pressure) of the left atrium. The pulmonary artery catheter is frequently referred to as a Swan-Ganz catheter, in honor of its inventors Jeremy Swan and William Ganz, from Cedars-Sinai Medical Center. Indications General indications are: Management of complicated myocardial infarction Hypovolemia vs cardiogenic shock Ventricular septal rupture (VSR) vs acute mitral regurgitation Severe left ventricular failure Right ventricular infarction Unstable angina Refractory ventricular tachycardia Assessment of respiratory distress Cardiogenic vs non-cardiogenic pulmonary edema Primary vs secondary pulmonary hypertension Assessment of types of shock Assessment of therapy Afterload reduction Vasopressors Beta blockers Intra-aortic balloon counter-pulsation Assessment of fluid requirement in critically ill patients Hemorrhage Sepsis Acute kidney injury Burns Management of postoperative open heart surgical patients Assessment of valvular heart disease Assessment of cardiac tamponade/constriction No study has definitively demonstrated improved outcome in critically ill patients managed with PA catheters. Given that the PA catheter is a monitoring tool and not a therapy in and of itself this is not entirely surprising. Justification for its continued use rests on a large body of clinical experience, disadvantages of other cardiac output monitoring systems, its ability to accurately measure pulmonary artery pressure, and the potential to use the catheter as a direct conduit for drug administration into the pulmonary artery. Procedure The catheter is introduced through a large vein—often the internal jugular, subclavian, or femoral veins. Ease of placement for a pulmonary artery catheter from easiest to difficult is: right internal jugular > left subclavian > left internal jugular > right subclavian. From this entry site, it is threaded through the right atrium of the heart, the right ventricle, and subsequently into the pulmonary artery. The passage of the