Pressure-volume index in head injury

Abstract

The authors studied intracranial pressure (ICP) and intracranial compliance as defined by the pressure-volume index (PVI) in 34 severely head-injured patients with a Glasgow Coma Scale score of 8 or less. The objective of the research was to determine if there was a correlation between the pressure-volume status and subsequent increase in ICP. The PVI and ICP measurements were obtained serially, and the temporal course of the pressure-volume status and ICP was determined during the 5-day period following injury. Aggressiveness of ICP was quantified by a therapy intensity level scale. A clear relationship between the PVI measured soon after injury and subsequent development of ICP emerged. Following mechanical trauma the PVI is reduced, and the degree of reduction and extent of biomechanical recovery are closely related to outcome and development of raised ICP.

Assessment of Craniospinal Pressure-Volume Indices

“…This was not expected because the general hypothesis is that PVI CC would be higher among the healthy and that a low PVI CC is pathologic. However, in the Table, studies using a slightly different pressure-volume model without a constant term account for the reports of high PVI CC values, 1,18 while those using a pressure-volume model with a constant term (as used in this study) have produced reports of PVI CC more similar to that generated in this study. 19,20 Aside from differences potentially originating in the choice of model, aging is known to influence the compliance of the craniospinal cavity, 20 and thus addition of normative data of elderly subjects is crucial.…”

The Course of Intracranial Pressure in Traumatic Brain Injury: Relation with Outcome and CT-characteristics

“…The Therapy Intensity Level (TIL) scale was used to monitor the stepwise therapeutic approach of ICP elevation by recording each measure that is applied to control ICP [11]. The TIL-scores range from 2 (ventilation and sedation) to 15 (barbiturates).…”

“…Duration of ICP monitoring varied from 1 to 24 days [median 7, interquartile range (IQR) [5][6][7][8][9][10][11]. Duration of mechanical ventilation varied from 1 to 50 days (median 15, IQR 8-23).…”

Traumatic Brain Edema in the Pathogenesis of Post-traumatic Hydrocephalus

“…Maset et al (1987) showed a clear correlation between PVI reduction and the subsequent development of normal ICP, both of which were related to the outcome. These results are close to our findings, but we also found that PVI reduction and increase of E developed even when ICP was held within the normal ranges (lower than 20 mmHg) , and that PVI reduced nonlinearly and E increased linearly during the growth of brain edema volume.…”