Martin H Deininger1, Astrid Weyerbrock. 1. Department of Neurosurgery, University of Freiburg Medical School, Breisacher Str. 64, D-79106 Freiburg, Germany. martin.deininger@uniklinik-freiburg.de
Abstract
BACKGROUND: In the subgroup of bedridden hydrocephalic patients with ventriculo-peritoneal shunts and gravitational valves, we occasionally observed persisting hydrocephalic complaints even when mechanical or infection-related obstruction was excluded. METHODS: To investigate the cause of these hydrocephalic symptoms, in vitro and in vivo analyses were used to determine valve opening, intra-abdominal and hydrostatic pressure of an Aesculap-Miethke 10/40 cm H2O gravitational valve at different angles of upper body and head inclination. FINDINGS: Since hydrostatic pressure is lacking, the resulting intra-ventricular pressures are shown to peak up to 27 cm H2O in supine patients with head, but not upper body inclined. CONCLUSIONS: We conclude that in the subgroup of bedridden patients with ventriculo-peritoneal shunts and gravitational valves, upright posture is a prerequisite for proper cerebrospinal fluid drainage.
BACKGROUND: In the subgroup of bedridden hydrocephalic patients with ventriculo-peritoneal shunts and gravitational valves, we occasionally observed persisting hydrocephalic complaints even when mechanical or infection-related obstruction was excluded. METHODS: To investigate the cause of these hydrocephalic symptoms, in vitro and in vivo analyses were used to determine valve opening, intra-abdominal and hydrostatic pressure of an Aesculap-Miethke 10/40 cm H2O gravitational valve at different angles of upper body and head inclination. FINDINGS: Since hydrostatic pressure is lacking, the resulting intra-ventricular pressures are shown to peak up to 27 cm H2O in supine patients with head, but not upper body inclined. CONCLUSIONS: We conclude that in the subgroup of bedridden patients with ventriculo-peritoneal shunts and gravitational valves, upright posture is a prerequisite for proper cerebrospinal fluid drainage.
Authors: Jeremiah N Johnson; Mohamed Samy Elhammady; Christian B Theodotou; Ramsey Ashour; Mohammad Ali Aziz-Sultan Journal: Asian J Neurosurg Date: 2014 Jul-Sep