Original article
The Pulmonary Artery Catheter: Gold Standard or Redundant Relic

https://doi.org/10.1016/j.jopan.2005.09.006Get rights and content

Pulmonary artery catheter (PAC) technology has changed significantly and use has decreased over the last 20 years. Barriers to use include: (a) increased patient risk with placement; (b) ability to measure similar variables via less invasive measures; (c) increased cost; (d) inaccurate measurement leading to misuse of PAC-derived variables; (e) incorrect interpretation and clinical application; and (f) lack of proven benefit for patient management. Advances in technology have allowed for continuous trending of hemodynamic parameters measured via the PAC. Patient risk is similar to that of central line placement; however risks associated with pulmonary artery infarction and rupture are inherent to the PAC. Less invasive assessment of cardiac output equals that of the PAC, whereas pulmonary capillary wedge pressure and mixed venous oxygen saturation monitoring are unique features of the PAC. Effective use of PAC data will require ongoing standardized education. More studies are needed on the cost-effectiveness of PAC monitoring as well as outcome benefits. Much of the data available from the PAC can be obtained via less invasive methods. However, the PAC continues to be useful in specific situations and remains the gold standard for comparison of new technologies. This paper discusses use of the PAC during the past 2 decades and reviews studies affecting its use in clinical practice.

Section snippets

PAC Monitoring 20 Years Ago

The PAC was initially used primarily with assessment and monitoring in acute cardiac disease.5 By 1985, the desire to differentiate between cardiac-related pulmonary edema and respiratory failure from acute lung injury resulted in frequent PAC insertion in the critical care areas. Furthermore, many surgeries were considered high risk and met criteria for perioperative PAC monitoring. Use in surgical patients was driven by several studies in the late 1980s and early 1990s, which demonstrated

PAC Monitoring Today

In 2005, use of the PAC is reserved for a minority of acutely ill and high-risk surgical patients.2, 5 The trend toward outcome-based practice challenged the common use of the PAC solely for the sake of data without proven outcome improvement.

Technological advances allow for simultaneous continuous monitoring of multiple pressures using transducer tubing with multiple separate transducers. Continuous trending capabilities include CO, stroke volume (SV), SVR, PVR, right ejection fraction (REF),

Barriers to PAC Use

In view of the plethora of monitoring options available thanks to technology, why are we seeing a decreased use of the PAC? Pinsky identified several reasons a physician might decide against using the PAC,4 including patient risk, availability of variables via less invasive measures, cost, inaccurate measurement with potential for incorrect interpretation and clinical application, and lack of known benefit (Table 1).

Patient Risk

Greatest patient risk related to PAC monitoring primarily is associated with inserting a central venous catheter. Complications due specifically to the PAC include pulmonary artery rupture with balloon inflation, serious ventricular dysrhythmias during placement, and endocardial lesions. Serious PAC-related complications occur in 0.1 to 0.5% of surgical patients. PA rupture is estimated to occur in 0.03 to 0.25% of cases, with mortality between 41-70% (Table 2).2, 13 As a result, some

Less Invasive Assessment Methods

Advances in technology have allowed for the development of noninvasive measurements for some hemodynamic parameters. New technologies include esophageal Doppler monitoring, echocardiography (Echo), central venous fiberoptic technology, pulse contour cardiac output, lithium dilution cardiac output, and thoracic electrical bioimpedance.17, 18 It is important to understand the physiologic principles of each method as well as the strengths and limitations for clinical application.

Notably, no

PAC Monitoring Cost

The cost of PA catheterization includes the cost of the equipment and personnel. Studies related to PAC cost are frequently fraught with uncontrolled variables such as underlying disease states, the practice environment, and lack of sample size.2 The more important question is whether PAC use is cost effective. Cost-effectiveness cannot be properly determined without establishing clinical effectiveness and therefore remains speculative.

Inaccurate Measurement and Incorrect Interpretation and Misuse

Lack of clinician knowledge and competency related to measurement and interpretation of PAC data has been identified in several studies. In 1990 Iberti et al found that only 67% of 496 North American physicians completed a 31-item examination on PACs accurately.19 In 1996, a survey of more than 1,000 critical care physicians found that although 83% of questions were answered correctly, one-third of the participants could not correctly identify a PCWP tracing or identify the major components of

Lack of Proven Benefit

A review of the literature demonstrates conflicting evidence for outcome benefits, particularly in medical patients. No clear evidence of benefit or harm managing patients with a PAC was the conclusion of a recent, randomized controlled trial with 1,014 patients.26 A need for PAC management protocols for specific populations was identified to validate the PAC as a useful technology.

Practice parameters for hemodynamic support of sepsis in adult patients were updated and published in 2004.27 The

Conclusion

Effort toward a standardized level of knowledge and expertise related to PAC use remains a priority. While educational resources are available, ways the resources are used and any effect on patient outcomes and practice changes remain unclear. It is vital that nursing continually reassess outcomes and apply evidence-based practices.

The PAC continues to be the gold standard for hemodynamic monitoring. This legacy of Doctors Swan and Ganz provides data that cannot be attained by other monitoring

Sherrie Smart, RN, BSN, CCRN, is Regional Clinical Specialist, Roche Diagnostic Corporation, Indianapolis, INPACU Per Diem Staff Nurse, CoxHealth, Springfield, MO.

References (28)

  • J. Headly

    Invasive hemodynamic monitoringApplying advanced technologies

    Nurs Q

    (1998)
  • B. Leeper

    Monitoring right ventricular volumesA paradigm shift

    AACN Clin Issues

    (2003)
  • M.L. Cheetham et al.

    Right ventricular end-diastolic volume index as a predictor of preload status in patients on positive end-expiratory pressure

    Crit Care Med

    (1998)
  • L. Diebel et al.

    End-diastolic volume versus pulmonary artery wedge pressure in evaluation cardiac preload in trauma patients

    J Trauma

    (1994)

    • Sherrie Smart, RN, BSN, CCRN, is Regional Clinical Specialist, Roche Diagnostic Corporation, Indianapolis, INPACU Per Diem Staff Nurse, CoxHealth, Springfield, MO.

    Editor’s note: Pulmonary artery catheter technology was invented and developed during the career of many a currently practicing perianesthsia nurse. Hemodynamic monitoring is therefore an age-old and oft-published topic. Today’s more discriminating use of the PAC is notable. Ms Smartt has previously written about cardiovascular and hemodynamic issues.

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    Copyright © 2005 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.