Intracranial pressure dynamics in clinical practice: online PC-based ICP monitoring system.

Correct patient management involves determining the exact point on the intracranial pressure/volume (P/V) curve that corresponds to the patient; this requires calculating intracranial elastance (IE). Intracranial pressure (ICP) monitoring systems should provide the necessary information for this purpose. An ICP monitoring unit is presented that acquires ICP, systemic arterial pressure (SAP) and airway pressure (AWP). The cerebral perfusion pressure (CPP) and the mean values and the peak-to-peak values of the two of them (ICPmean, SAPmean, ICPp-p, SAPp-p,) are calculated. Graphs display the temporal evolution (TE) of the ICP and SAP, as well as histograms of the ICP (%) and intracranial pulse amplitude (ICPAmP) with respect to the ICP or CPP during the preceding 3, 6, 12 or 24 h of monitoring. By digital filtering the ICP respiratory and cardiac components (RCICP, CCICP) are calculated. Finally, the pulse amplitudes (AmP) of the ICP, CCICP and RCICP are computed, as well as the average pulses per minute of SAP, CCICP, AWP and RCICP. Two off-line pulse-amplitude and pulse-morphology oriented toolkits display the afore-mentioned curves, histograms and average pulses per minute, and other additional ones, in order to achieve a deeper patient monitoring study.