Interleukin-1 beta enhances spinal cord blood flow after intrathecal administration in the normal rat

The effects of acute intrathecal recombinant human interleukin-1 beta (rhIL-1 beta) administration on spinal cord blood flow (SCBF), volume, and velocity were determined by laser-Doppler flowmetry in normal anesthetized rats with the use of a randomized and blinded protocol. The intrathecal administration of rhIL-1 beta (0.16-16 ng) produced a dose-dependent increase in SCBF that was not related to changes in blood pressure; arterial pH, PO2, PCO2; or spinal cord temperature. The IL-1 beta-induced enhancement of SCBF was directly proportional to the resultant elevation of spinal cord rhIL-1 beta content and was significantly correlated with an elevated blood velocity. The IL-1 receptor antagonist (IL-1ra) in concentrations 50- and 200-fold higher than IL-1 beta completely blocked the IL-1 beta-induced increase in SCBF when both compounds were administered concomitantly, but when administered alone, IL-1ra did not affect SCBF or other parameters. This suggests that IL-1 beta action was mediated by a specific interaction with an IL-1 membrane receptor site. The results suggest a role of IL-1 beta in the regulation of spinal cord hemodynamics. A potential pharmacological approach using IL-1 agonists for the treatment of the delayed appearance of posttraumatic spinal ischemia is proposed.

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Validation of laser-Doppler flowmetry in measurement of spinal cord blood flow

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1989.257.2.h674 ◽

1989 ◽

Vol 257 (2) ◽

pp. H674-H680 ◽

Cited By ~ 2

Author(s):

P. J. Lindsberg ◽

J. T. O'Neill ◽

I. A. Paakkari ◽

J. M. Hallenbeck ◽

G. Feuerstein

Keyword(s):

Spinal Cord ◽

Blood Flow ◽

Cord Blood ◽

Laser Doppler Flowmetry ◽

Laser Doppler ◽

Microvascular Blood Flow ◽

Base Line ◽

Spinal Cord Blood Flow ◽

Flow Measurements ◽

Doppler Flowmetry

Laser-Doppler flowmetry (LDF) is a non-invasive method for continuous on-line monitoring of microvascular blood flow. LDF has previously been validated with established methods in various tissues, yet its validity and resolution in the central nervous system (CNS) remain unclear. We compared LDF with the microsphere method (MS) using two independent laser probes placed on the dorsal lumbar spinal cord (L5 laminectomy) of anesthetized rabbits (n = 9). After base-line flow measurements, spinal cord blood flow (SCBF) was increased (up to 50%) with phenylephrine (10-80 micrograms.kg-1.min-1 iv) and decreased (up to 50%) with chlorisondamine (10 mg/kg iv) or other stimuli. The percentage changes of lumbar SCBF and vascular resistance (VR) from the base line obtained by LDF and MS excellently agreed (rBF = 0.86, rVR = 0.94, P less than 0.0001). LDF estimated also the absolute SCBF values parallel to MS (r = 0.77, P less than 0.001). In conclusion, the validity of LDF in estimating the SCBF and dynamic changes of BF and VR is confirmed. Therefore, LDF may prove useful for monitoring CNS microcirculation in normal or pathophysiological states.

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Towards rapid intraoperative axial localization of spinal cord ischemia with epidural diffuse correlation monitoring

PLoS ONE ◽

10.1371/journal.pone.0251271 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0251271

Author(s):

David R. Busch ◽

Wei Lin ◽

Chia Chieh Goh ◽

Feng Gao ◽

Nicholas Larson ◽

...

Keyword(s):

Spinal Cord ◽

Blood Flow ◽

Cord Blood ◽

Spinal Cord Ischemia ◽

Correlation Spectroscopy ◽

Spinal Cord Blood Flow ◽

Doppler Flowmetry ◽

Spatially Resolved ◽

Highly Correlated ◽

Sensitivity Specificity

Spinal cord ischemia leads to iatrogenic injury in multiple surgical fields, and the ability to immediately identify onset and anatomic origin of ischemia is critical to its management. Current clinical monitoring, however, does not directly measure spinal cord blood flow, resulting in poor sensitivity/specificity, delayed alerts, and delayed intervention. We have developed an epidural device employing diffuse correlation spectroscopy (DCS) to monitor spinal cord ischemia continuously at multiple positions. We investigate the ability of this device to localize spinal cord ischemia in a porcine model and validate DCS versus Laser Doppler Flowmetry (LDF). Specifically, we demonstrate continuous (>0.1Hz) spatially resolved (3 locations) monitoring of spinal cord blood flow in a purely ischemic model with an epidural DCS probe. Changes in blood flow measured by DCS and LDF were highly correlated (r = 0.83). Spinal cord blood flow measured by DCS caudal to aortic occlusion decreased 62%. This monitor demonstrated a sensitivity of 0.87 and specificity of 0.91 for detection of a 25% decrease in flow. This technology may enable early identification and critically important localization of spinal cord ischemia.

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Spinal cord blood flow changes following systemic hypothermia and spinal cord compression injury: an experimental study in the rat using Laser-Doppler flowmetry

Spinal Cord ◽

10.1038/sj.sc.3101127 ◽

2001 ◽

Vol 39 (2) ◽

pp. 74-84 ◽

Cited By ~ 50

Author(s):

H Westergren ◽

M Farooque ◽

Y Olsson ◽

A Holtz

Keyword(s):

Spinal Cord ◽

Experimental Study ◽

Blood Flow ◽

Cord Blood ◽

Cord Compression ◽

Compression Injury ◽

Spinal Cord Blood Flow ◽

Doppler Flowmetry ◽

Systemic Hypothermia ◽

Flow Changes

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Laser-Doppler Evaluation of Spinal Cord Blood Flow After Intrathecal Administration of an N???Methyl???D???Aspartate Antagonist in Rats

Anesthesia & Analgesia ◽

10.1213/00000539-199405000-00016 ◽

1994 ◽

Vol 78 (5) ◽

pp. 925???931 ◽

Cited By ~ 9

Author(s):

Jens D. Kristensen ◽

Rolf Karlsten ◽

Torsten Gordh

Keyword(s):

Spinal Cord ◽

Blood Flow ◽

Cord Blood ◽

Intrathecal Administration ◽

Laser Doppler ◽

Spinal Cord Blood Flow ◽

Doppler Evaluation

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Spatially resolved optical monitoring of spinal cord blood flow with a minimally invasive, multi-level epidural probe

10.1101/2020.10.06.326900 ◽

2020 ◽

Author(s):

David R. Busch ◽

Wei Lin ◽

Chia Chieh Goh ◽

Feng Gao ◽

Nicholas Larson ◽

...

Keyword(s):

Spinal Cord ◽

Blood Flow ◽

Cord Blood ◽

Spinal Cord Ischemia ◽

Correlation Spectroscopy ◽

Spinal Cord Blood Flow ◽

Doppler Flowmetry ◽

Spatially Resolved ◽

Highly Correlated ◽

Sensitivity Specificity

AbstractSpinal cord ischemia leads to iatrogenic injury in multiple surgical fields, and the ability to immediately identify onset and anatomic origin of ischemia is critical to its management. Current clinical monitoring, however, does not directly measure spinal cord blood flow, resulting in poor sensitivity/specificity, delayed alerts, and delayed intervention. We have developed an epidural device employing diffuse correlation spectroscopy (DCS) to monitor spinal cord ischemia continuously at multiple positions. We investigate the ability of this device to localize spinal cord ischemia in a porcine model and validate DCS versus Laser Doppler Flowmetry (LDF).Specifically, we demonstrate continuous (>0.1Hz) spatially resolved (3 locations) monitoring of spinal cord blood flow in a purely ischemic model with an epidural DCS probe. Changes in blood flow measured by DCS and LDF were highly correlated (r=0.83). Spinal cord blood flow measured by DCS caudal to aortic occlusion decreased 62%, with a sensitivity of 0.87 and specificity of 0.91 for detection of a 25% decrease in flow. This technology may enable early identification and critically important localization of spinal cord ischemia.

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