Premium
Recording of intracranial pressure in conscious rats via telemetry (668.2)
Author(s) -
Guild SarahJane,
Budgett David,
Malpas Simon
Publication year - 2014
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.28.1_supplement.668.2
Subject(s) - intracranial pressure , telemetry , medicine , catheter , biomedical engineering , hydrocephalus , anesthesia , pressure sensor , surgery , aerospace engineering , physics , engineering , thermodynamics
Measurement of intracranial pressure (ICP) is a critical diagnostic measure in treating head trauma, intracerebral hemorrhage and hydrocephalus. The pressure values are generally between 5‐15 mmHg with >20 mmHg considered abnormal. There is a scarcity of animal models of chronic ICP measurement in part associated with the difficulty of measuring ICP chronically with good accuracy. Previous telemetry devices utilizing fluid filled catheters have proved problematic due to movement artefacts. The purpose of this study was to develop the methodology to record ICP in the conscious rat using a solid state pressure sensor by telemetry. We implanted TRM54PP telemetry devices which incorporate solid state 2 Fr (0.6 mm) sensors in rats. Arterial pressure (AP) was measured via the abdominal aorta and the other pressure catheter (25cm long) was tunnelled subcutaneously to the skull and inserted thru the dura to lie against the brain tissue for the measurement of ICP. All rats appeared healthy and recovered well from surgery. ICP and AP were successfully recorded in conscious rats for up to 4 weeks post‐surgery. When rats were resting quietly, a strong respiratory rhythm was seen in both signals. Postural changes during head up and head down tilt tests resulted in reversible decreases and increases of ICP as expected. No visible damaged from the ICP catheter was found on the brain surface at post‐mortem. The stability and fidelity of the signals were excellent over time. In a second group of animals, basal cistern injection of kaolin was used to increase ICP as a model of communicating hydrocephalus. Grant Funding Source : Supported by the Neurological Foundation of New Zealand