Direct arterial pressure monitoring

Abstract

Direct arterial pressure monitoring is a common practice in the modern intensive care unit and during complex anaesthesia cases. The methods for catheter introduction and maintenance are widely described and used. However, in the past few years there have been new developments and controversies surrounding direct arterial pressure measurement. First, rugged, inexpensive and convenient disposable transducers are supplanting the former expensive, fragile reusable transducers. Second, the fidelity or dynamic response required to reproduce the ‘real’ arterial pressure waveform continues to be a subject of controversy and concern. This review attempts to clarify the dynamic response issues and show how to test pressure monitoring systems in the clinical setting. Third, the arterial pressure waveform is distorted as it is transmitted from the aorta to peripheral arteries. Fourth, computer processing of the arterial waveform that presents ‘digital’ results must be improved. In some situations, the digitally displayed numbers ‘lie’. Despite the issues noted the use of direct arterial pressure measurement is a convenient, safe, and helpful method for continuously monitoring patients.