Short paper

The effect of whole body position on lumbar cerebrospinal fluid opening pressure

Pasiri Sithinamsuwan^1,2 , Nakorn Sithinamsuwan² , Sirakarn Tejavanija² , Chesda Udommongkol^1,2 and Samart Nidhinandana^1,2

¹  Division of Neurology, Phramongkutklao Hospital and College of Medicine, Bangkok, 10400, Thailand

²  Department of Medicine, Phramongkutklao Hospital and College of Medicine, Bangkok, 10400, Thailand

author email corresponding author email

Cerebrospinal Fluid Research 2008, 5:11doi:10.1186/1743-8454-5-11

Published:	2 July 2008

Abstract

We compared cerebrospinal fluid (CSF) opening pressure measurements in the lumbar subarachnoid space between the flexed position (F-OP) and relaxed position (R-OP) in recumbent patients. We devised an equation for using F-OP to determine the existence of raised intracranial pressure (ICP). Patients (n = 83) underwent lumbar puncture while in the flexed lateral decubitus position and then were moved to the relaxed position. F-OP and R-OP were measured with a water manometer. R-OP > 180 mmH₂O plus relevant clinical signs were taken as indicators of raised intracranial pressure. Mean pressures for F-OP and R-OP were 178.54 and 160.52 mmH₂O respectively, p <0.001. When F-OP > 180, raised ICP could be significantly over diagnosed. The authors recommend an equation [R-OP_{(calculated, mmH2O)} = 0.885 × F-OP_{(measured, mmH2O)}] or using 200 mmH₂O as the threshold for increased ICP with flexed posture.