Background: The process of measuring intracranial pressure (ICP) can be accomplished using a variety of monitors placed primarily either in the ventricles or brain parenchyma.
Objective: There is inadequate data to support the conclusion that ICP measured simultaneously from 2 different sites using 2 different devices produces similar findings in the same subject. The purpose of this study was to identify the correlation between simultaneous measurements from both an external ventricular drain (EVD) and an intraparenchymal monitor (IPM).
Methods: In this retrospective observational study, manual chart abstraction was used to obtain time-indexed ICP values during a period of 2 years from patients diagnosed with severe traumatic brain injury who had received simultaneous EVD and IPM placement.
Results: When all time points were compared, the correlation between EVD and IPM was strong (r = 0.6955). However, when limiting the ICP values to be <20 or <25 in either the EVD or the IPM, the correlation was noted to be weaker (r = 0.3576 and r = 0.4232, respectively).
Conclusion: There is inadequate evidence to support that intraparenchymal ICP values can be treated in a similar manner to ICP values obtained from an EVD.
Abbreviations: CSF, cerebrospinal fluidEVD, external ventricular drainICP, intracranial pressureIPM, intraparenchymal monitorTBI, traumatic brain injury.