There has been little evidence to show that the use of PA catheters improves outcome. Recently, a small number of papers were published which suggested that PA catheters actually caused harm. The paper by Connors et al. is one example. They looked at nearly 6000 patients going through an ICU in the USA. Just over 2000 had PA catheters. They adjusted for severity of illness and paired PA catheter patients with similar non-PA catheter patients. The PA catheter patients had worse outcomes and longer ICU stays (thus increasing costs). Possible explanations include:
• Clinicians tend to put PA catheters in patients who are sicker and not responding to conventional therapy.
• Clinicians may not be using the PA catheter appropriately - that is, relying on numbers rather than clinical assessment.
• Studies in the USA may not apply to European intensive care practice.
Several randomised controlled trials are now in progress to answer these questions and early results suggest that PA catheters do not increase mortality. Rhodes et al. looked at 200 patients in intensive care. In this study the PA catheter did not affect outcome either way. Clinicians were allowed to use clinical discretion when manipulating haemodynamic values rather than work to a protocol, and this fact may be significant. Larger trials are awaited that will help to answer the question of PA catheter use more definitively. In the meantime, use of PA catheters varies between different intensive care units.
Was this article helpful?