Analysis of intracranial pressure pulse waveform in studies on cerebrospinal compliance: a narrative review

Abstract

Continuous monitoring of mean intracranial pressure (ICP) has been an essential part of neurocritical care for more than half a century. Cerebrospinal pressure–volume compensation, i.e., the ability of the cerebrospinal system to buffer changes in volume without substantial increases in ICP, is considered an important factor in preventing adverse effects on the patient’s condition that are associated with ICP elevation. However, existing assessment methods are poorly suited to the management of brain injured patients as they require external manipulation of intracranial volume. In the 1980s, studies suggested that spontaneous short-term variations in the ICP signal over a single cardiac cycle, called the ICP pulse waveform, may provide information on cerebrospinal compensatory reserve. In this review we discuss the approaches that have been proposed so far to derive this information, from pulse amplitude estimation and spectral techniques to most recent advances in morphological analysis based on artificial intelligence solutions. Each method is presented with focus on its clinical significance and the potential for application in standard clinical practice. Finally, we highlight the missing links that need to be addressed in future studies in order for ICP pulse waveform analysis to achieve widespread use in the neurocritical care setting.

Automatic calculation for pulse wave morphology change: a rheoencephalographic study

“…The comprehensive clinical aspect of ICP elevation was presented by [10,11]. The consequence of computerized monitoring has resulted in several new methods, speci cally the analysis of ICP pulse waves [12][13][14][15][16][17][18][19]. Measuring the P2/P1 ratio is used in the B4C system, a noninvasive intracranial compliance monitoring device [17] by [20].…”

“…Measuring the P2/P1 ratio is used in the B4C system, a noninvasive intracranial compliance monitoring device [17] by [20]. The P1/P2 ratio of the ICP pulse wave was compared to [19].…”

Intracranial pressure and pulsatility in different head and body positions

“…ICP pulsatility (pulse amplitude) is the amplitude of the cardiac-induced fluctuation in ICP and is an important, indirect biomarker of intracranial compliance. [35][36][37] Compliance is the capacity of the intracranial compartment to buffer an increase in volume against an increase in pressure. 36,37 Pulsatility and intracranial compliance are inversely related such that greater pulsatility reflects decreased compliance.…”