Experimental comparison of the measurement accuracy of the Licox(®) and Raumedic (®) Neurovent-PTO brain tissue oxygen monitors.
BACKGROUND
Only a few experimental reports are available on the direct comparison of Licox(®) and Raumedic(®)-Neurovent-PTO brain tissue oxygen pressure (P(br)O(2)) monitors. We compared the two systems regarding their measurement properties under experimental in vitro and in vivo conditions.


METHODS
Eight Licox(®) and Raumedic(®) Neurovent-PTO(®) sensors were tested for 10 min at 37°C, atmospheric pressure, at an oxygen content of 0% and 100% before and after the in vivo test. The same probes were implanted in German landrace pigs, which underwent hepatectomy. The mean P(br)O(2) values were recorded every minute. An O(2) challenge with inhalation of 100% O(2) for 10 min was performed 2 h post-abdominal surgery.


RESULTS
At 0% O(2) content values varied from 0.2 to 7 mmHg, at 100% O(2) content from 130 to 165 mmHg. No difference between probes was found. In vivo tests: Raumedic® showed higher P(br)O(2) values (mean +6.3 mmHg, p < 0.0001) compared with Licox®. During O(2) challenge, both probes responded similarly; however, Raumedic(®) had a 10% higher response amplitude (p < 0.005). After explantation there was again no difference between the two sensors.


CONCLUSIONS
Raumedic(®) sensors measured higher P(br)O(2) values. There was no significant difference regarding overall measurement of in vitro accuracy between the two probes, which proved to be robust when used consecutively for longer periods and in different environments.
Department of Neurosurgery, Eberhard Karls University Hospital, Tübingen, Germany. matthias.morgalla@med.uni-tuebingen.de
Matthias H
MH
Morgalla
R
R
Haas
G
G
Grözinger
Christian
C
Thiel
Karolin
K
Thiel
Martin U
MU
Schuhmann
Martin
M
Schenk
D000465:Algorithms; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000378:metabolism*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D005215:Fasting; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D010100:Oxygen / Q000032:analysis* / Q000378:metabolism; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013552:Swine
D010100:Oxygen