Monitoring arterial blood pressure: what you may not know.

Hemodynamic monitoring is a costly procedure, both materially and with regard to nursing time involved to ensure proper functioning of the monitoring system and correct interpretation of the data obtained. Dynamic response testing is the ideal method of confirming the ability of a monitoring system to accurately reproduce hemodynamic waveforms. MAP is a stable hemodynamic parameter, because it is least affected by monitoring method, catheter insertion site, the dynamic response characteristics of the catheter system, and wave reflection. MAP provides the best estimate of central aortic pressure and is the main hemodynamic parameter monitored by the neurohormonal system to control blood pressure. The superior informational value of MAP provides strong support for its preferred use in clinical practice, especially when use of vasoactive drugs is started or the dosages of these drugs are titrated. However, numerically satisfactory ABP or MAP values are not necessarily related to adequate peripheral tissue perfusion and organ system function. For optimal management of patients, data obtained from assessment tools such as hemodynamic monitoring devices must be integrated with information gained from clinical assessment of patients' status.