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Published on: October 17, 2017
Intracranial Pressure Values Are Highly Variable After Cerebral Spinal Fluid Drainage
Michael Rogers1, Sonja E Stutzman, Folefac D Atem
1Michael Rogers, BSN RN CCRN, is Bedside Nurse, Neurointensive Care Unit, Zale-Lipshy Hospital, University of Texas Southwestern Medical Center, Dallas, TX. Sonja E. Stutzman, PhD, is Clinical Research Manager, University of Texas Southwestern Medical Center, Dallas, TX. Folefac D. Atem, PhD MS, is Assistant Professor of Biostatistics, University of Texas Southwestern Medical Center, Dallas, TX. Samarpita Sengupta, PhD, is Scientific Research Writer, University of Texas Southwestern Medical Center, Dallas, TX. Babu Welch, MD FAANS, is Associate Professor of Neurosurgery and Radiology, University of Texas Southwestern Medical Center, Dallas, TX. Questions or comments about this article may be directed to DaiWai M. Olson, PhD RN CCRN FNCS, at Daiwai.Olson@utsouthwestern.edu. He is an Associate Professor, Departments of Neurology and Neurotherapeutics and of Neurosurgery, University of Texas Southwestern Medical Center, Dallas, TX. The study was funded by the Agnes Marshal Walker Foundation and the Integra Foundation.
Observing intracranial pressure (ICP) waveforms after clamping an external ventricular drain (EVD) for at least 5 minutes is safe and provides an accurate patient status. This duration ensures reliable ICP monitoring without missing critical changes.
Area of Science:
- Neuroscience
- Critical Care Medicine
- Nursing
Background:
- Intracranial pressure (ICP) monitoring via external ventricular drains (EVDs) is crucial in neurocritical care.
- Nurses are primarily responsible for observing, adjudicating, and documenting ICP values.
- Cerebrospinal fluid drainage through EVDs temporarily halts ICP monitoring.
Purpose of the Study:
- To determine the optimal duration for clamping an EVD to obtain an accurate ICP reading.
- To establish an evidence-based standard for post-clamping ICP waveform observation.
- To inform nursing practice regarding ICP monitoring after EVD manipulation.
Main Methods:
- A study involving 30 subjects undergoing continuous ICP monitoring.
- ICP waveforms were observed for 15 minutes after clamping the EVD.
- Conditional probabilities of observing peak ICP within specific timeframes were calculated.
Main Results:
- No universal ICP pattern was observed after EVD clamping.
- A 5-minute observation period yielded a 0.0181 conditional probability of capturing the highest ICP.
- Extending observation to 10 minutes increased this probability to 0.0402, with no interventions required.
Conclusions:
- At least 5 minutes of ICP monitoring post-EVD clamping is recommended.
- This duration is considered safe and necessary for reflecting true ICP values.
- The findings support an evidence-based practice for ICP monitoring in neurocritical care settings.
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