The pulmonary artery catheter in 2008 - A (finally) maturing modality?

Abstract

The first description of the flow-directed pulmonary artery catheter (PAC) was published in the 1970s by Jeremy Swan and William Ganz. Ever since its clinical debut, many controversies surrounded the use of the PAC. Regardless of these controversies, the most fundamental issues surrounding this hemodynamic monitoring device remain unresolved, including the exact indications, contraindications, identification of patients who potentially benefit from this technology, and the way we interpret and use PAC-derived parameters. Despite recent intensification of attacks against the use of the PAC by its opponents, it seems overly harsh to discount a technology that might be beneficial in appropriately selected clinical situations, especially when considering the fact that our true knowledge of this technology is somewhat limited. In fact, the PAC may still play an important role considering the resurgence of the concepts of euvolemic resuscitation and hemodynamic sufficiency. Republished with Permission from: Stawicki SP, Prosciak MP. The pulmonary artery catheter in 2008 - a (finally) maturing modality? OPUS 12 Scientist 2008;2(4):5-9.

Keywords: Euvolemic resuscitation; hemodynamic monitoring; hemodynamic sufficiency; pulmonary artery catheter; surgical critical care.

Figure 1

The concept of hemodynamic sufficiency. In addition to adequate treatment of the underlying pathologic condition, the perfect resuscitation requires perfect balance between fluid resuscitation, inotrope and/or vasopressor use, and the clearance of by-products of anaerobic metabolism (i.e., metabolic debris). Source: Gracias and McGonigal.[24]

Figure 2

A proposed resuscitation algorithm to help facilitate the achievement of hemodynamic sufficiency. Using an automotive analogy, note the use of central venous pressure as the “accelerator” and the use of pulmonary artery catheter as the “brake” pedal to continued fluid resuscitation. Source: Vincent[23]

Figure 3

The concept of organ perfusion pressure and its relationship to the balance of the mean arterial pressure (MAP), the central venous pressure, and the efficient output of the cardiac pump. Imbalances between the arterial inflow and central venous pressures affect the end organ flow efficiency (curved red and blue arrows) and contribute to venous congestion and organ dysfunction. Eventually, the state of iatrogenic edema leads to inefficient end organ functioning. Note that, in addition to inotrope regulation of cardiac pump, both the arterial and central venous sides of the equation can be modified using a combination of vasopressor, volume removal or resuscitation, or continuous renal replacement therapy (in cases of renal failure). This diagram demonstrates the potential roles of central venous pressure as the “accelerator” and the pulmonary artery catheter as the “brake pedal”. Also note that central venous pressure in combination with transthoracic or (preferably) transesophageal echocardiography is capable of providing clinical information similar to that provided by the pulmonary artery catheter. Other less invasive methods of hemodynamic monitoring await full clinical validation