Objective: To determine the statistical characteristics of blood pressure (BP) readings from a large number of head-injured patients.
Methods: The BrainIT group has collected high time-resolution physiological and clinical data from headinjured patients who require intracranial pressure (ICP) monitoring. The statistical features of this dataset of BP measurements with time resolution of 1 min from 200 patients is examined. The distributions of BP measurements and their relationship with simultaneous ICP measurements are described.
Results: The distributions of mean, systolic and diastolic readings are close to normal with modest skewing towards higher values. There is a trend towards an increase in blood pressure with advancing age, but this is not significant. Simultaneous blood pressure and ICP values suggest a triphasic relationship with a BP rising at 0.28 mm Hg/mm Hg of ICP, for ICP up to 32 mm Hg, and 0.9 mm Hg/mm Hg of ICP for ICP from 33 to 55 mm Hg, and falling sharply with rising ICP for ICP .55 mm Hg.
Conclusions: Patients with head injury appear to have a near normal distribution of blood pressure readings that are skewed towards higher values. The relationship between BP and ICP may be triphasic.
Mitchell P, Gregson BA, Piper I, Citerio G, Mendelow AD, Chambers IR. Blood pressure in head-injured patients. J. Neurol. Neurosurg. Psychiatry 2007;78;399-402.
Dr. Iain R. Chambers, Cleveland Unit, Middlesbrough. Tel: +44 (0)1642-854-778.
Regional Medical Physics Department, Newcastle General Hospital, Newcastle upon Tyne, NE4 6BE, UK.
Tel: +44 (0)191-233-6161 Fax: +44 (0)191-226-0970 E-mail: webmaster@rmpd.org.uk Web: http://www.rmpd.org.uk
By using this site you agree to our Terms and Conditions of Use. Please read our legal page.
Regional Medical Physics Department, a Clinical Directorate of the Newcastle upon Tyne Hospitals NHS Foundation Trust.
Copyright ©1999-2008 All Rights Reserved. Revised 28 April, 2008.
