PMID- 10930012
OWN - NLM
STAT- MEDLINE
DCOM- 20000831
LR  - 20151119
IS  - 0022-3085 (Print)
IS  - 0022-3085 (Linking)
VI  - 93
IP  - 2
DP  - 2000 Aug
TI  - Continuous monitoring of regional cerebral blood flow: experimental and clinical 
      validation of a novel thermal diffusion microprobe.
PG  - 265-74
AB  - OBJECT: Current clinical neuromonitoring techniques lack adequate surveillance of 
      cerebral perfusion. In this article, a novel thermal diffusion (TD) microprobe is 
      evaluated for the continuous and quantitative assessment of intraparenchymal 
      regional cerebral blood flow (rCBF). METHODS: To characterize the temporal 
      resolution of this new technique, rCBF measured using the TD microprobe (TD-rCBF) 
      was compared with rCBF levels measured by laser Doppler (LD) flowmetry during 
      standardized variations of CBF in a sheep model. For validation of absolute 
      values, the microprobe was implanted subcortically (20 mm below the level of 
      dura) into 16 brain-injured patients, and TD-rCBF was compared with simultaneous 
      rCBF measurements obtained using stable xenon-enhanced computerized tomography 
      scanning (sXe-rCBF). The two techniques were compared using linear regression 
      analysis as well as the Bland and Altman method. Stable TD-rCBF measurements 
      could be obtained throughout all 3- to 5-hour sheep experiments. During 
      hypercapnia, TD-rCBF increased from 49.3+/-15.8 ml/100 g/min (mean +/- standard 
      deviation) to 119.6+/-47.3 ml/100 g/ min, whereas hypocapnia produced a decline 
      in TD-rCBF from 51.2+/-12.8 ml/100 g/min to 39.3+/-5.6 m/100 g/min. Variations in 
      mean arterial blood pressure revealed an intact autoregulation with pressure 
      limits of approximately 65 mm Hg and approximately 170 mm Hg. After cardiac 
      arrest TD-rCBF declined rapidly to 0 ml/100 g/min. The dynamics of changes in 
      TD-rCBF corresponded well to the dynamics of the LD readings. A comparison of 
      TD-rCBF and sXe-rCBF revealed a good correlation (r = 0.89; p < 0.0001) and a 
      mean difference of 1.1+/-5.2 ml/100 g/min between the two techniques. 
      CONCLUSIONS: The novel TD microprobe provides a sensitive, continuous, and 
      real-time assessment of intraparenchymal rCBF in absolute flow values that are in 
      good agreement with sXe-rCBF measurements. This study provides the basis for the 
      integration of TD-rCBF into multimodal monitoring of patients who are at risk for 
      secondary brain injury.
FAU - Vajkoczy, P
AU  - Vajkoczy P
AD  - Department of Neurosurgery and Anesthesiology, Klinikum Mannheim, University of 
      Heidelberg, Germany. peter.vajkoczy@nch.ma.uni-heidelberg.de
FAU - Roth, H
AU  - Roth H
FAU - Horn, P
AU  - Horn P
FAU - Lucke, T
AU  - Lucke T
FAU - Thome, C
AU  - Thome C
FAU - Hubner, U
AU  - Hubner U
FAU - Martin, G T
AU  - Martin GT
FAU - Zappletal, C
AU  - Zappletal C
FAU - Klar, E
AU  - Klar E
FAU - Schilling, L
AU  - Schilling L
FAU - Schmiedek, P
AU  - Schmiedek P
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Neurosurg
JT  - Journal of neurosurgery
JID - 0253357
RN  - 3H3U766W84 (Xenon)
SB  - IM
MH  - Adolescent
MH  - Animals
MH  - *Cerebrovascular Circulation
MH  - Craniocerebral Trauma/physiopathology
MH  - Equipment Design
MH  - Humans
MH  - Intracranial Pressure
MH  - Laser-Doppler Flowmetry/*instrumentation
MH  - Microcirculation/physiology
MH  - Monitoring, Physiologic
MH  - Sensitivity and Specificity
MH  - Sheep
MH  - Temperature
MH  - Tomography, X-Ray Computed
MH  - Xenon
EDAT- 2000/08/10 11:00
MHDA- 2000/09/02 11:01
CRDT- 2000/08/10 11:00
PHST- 2000/08/10 11:00 [pubmed]
PHST- 2000/09/02 11:01 [medline]
PHST- 2000/08/10 11:00 [entrez]
AID - 10.3171/jns.2000.93.2.0265 [doi]
PST - ppublish
SO  - J Neurosurg. 2000 Aug;93(2):265-74. doi: 10.3171/jns.2000.93.2.0265.