alexa Epidural anesthesia and acutely increased intracranial pressure. Lumbar epidural space hydrodynamics in a porcine model.


Journal of Anesthesia & Clinical Research

Author(s): Grocott HP, Mutch WA

Abstract Share this page

Abstract BACKGROUND: The effects of epidural injection on intracranial pressure (ICP), lumbar epidural pressure, cerebral blood flow (CBF), and spinal cord blood flow (SCBF) were studied after acutely increased ICP in swine. METHODS: Twenty pigs, anesthetized with isoflurane and mechanically ventilated to maintain normocarbia, had two Tuohy needles placed in the lumbar epidural space. The ICP, lumbar epidural pressure, heart rate, mean arterial pressure, and central venous pressure were monitored. All animals had a Fogarty catheter placed in the parietal epidural space. Six pigs were randomized to a normal ICP group (group N) and eight pigs to an increased ICP group by inflation of the Fogarty catheter balloon (group R). Each pig had 0.33 of 2.0\% carbonated lidocaine injected over 20 s via an epidural needle placed at L3. The ICP and lumbar epidural pressure were then monitored continuously for 30 min. Pressure-time data were fit to traditional compartmental models. Epidural elastance and resistance were calculated using a derivation of the Windkessel theory. An additional six pigs had ICP elevated as in group R and CBF and SCBF measured using radioactive microspheres at five time periods: baseline, 0-60 s, 100-160 s, 200-260 s, and at 30 min after epidural injection. RESULTS: The animals did not differ with respect to heart rate, central venous pressure, or mean arterial pressure at baseline. The ICP was 10 +/- 2 mmHg in group N, and 24 +/- 2 mmHg after balloon inflation in group R. After epidural injection, peak ICP was significantly greater in group R (76 +/- 22 vs. 54 +/- 17 mmHg) but not different by 30 min (17 +/- 5 vs. 11 +/- 1 mmHg). Epidural elastance in group N was 8.3 +/- 3.1 and 12.8 +/- 3.0 in group R (P = 0.045). Epidural resistance was 1,330 +/- 590 in group N and 2,220 +/- 600 in group R (P = 0.038). The CBF and SCBF were less than 10\% of baseline during the 0- to 60-s time period after epidural injection. Thereafter, CBF and SCBF did not differ from baseline values. CONCLUSIONS: In this porcine model, epidural injection increased ICP. With increased ICP at baseline, more pronounced increases in ICP followed epidural injection. With increased baseline ICP, both epidural elastance and resistance increased compared with controls. The CBF and SCBF were markedly reduced immediately after local anesthetic injection into the epidural space.
This article was published in Anesthesiology and referenced in Journal of Anesthesia & Clinical Research

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version