Intracranial pressure and clinical status: assessment of two intracranial pressure transducers

The aim of this study was to determine the in vivo accuracy and reliability of intracranial pressure (ICP) measurement using the Codman MicroSensor by comparison with the Camino TCP transducer and associated clinical and radi ological information. Paired ICP readings were recorded every minute in 17 patients. A total of 5 6 790 validated paired measurements were obtained over a wide range of ICP values (-16 nun Hg to 114 mm Hg). Recording periods ranged from 3 hours to 6 days (median 31 hours). In 11 patients the MicroSensor and Camino readings were in good agreement. Paired readings were within 10 mm Hg fur 99% of the recording time and both readings were compatible with clinical intracranial events at all times (i n one case it was not possible to verify the clinical information). In six patients large differences occurred between transducer readings (>10 mm Hg apart for 42% of the recording period). In one case, either reading could h ave been compatible with intracranial clinical events. In two cases, althou gh both readings were comparable, Camino readings were more consistent with clinical and radiological Endings. In three cases, the MicroSensor reading s were inconsistent with the clinical condition of the patients whereas the Camino readings were compatible. These results suggest that, during routine clinical use in our department, the MicroSensor provided misleading information in 18% of our patients and thus is not sufficiently reliable for routine use in the detection of adver se clinical events.