JOURNAL HOME CME HOME THIS MONTH PAST ISSUES ETOC COLLECTIONS AUTHORS REVIEWERS EDITORIAL BOARD FEEDBACK RSS HELP
		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Data Supplement Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (23) Citing Articles via Google Scholar Google Scholar Articles by Prielipp, R. C. Articles by Butterworth, J. Search for Related Content PubMed PubMed Citation Articles by Prielipp, R. C. Articles by Butterworth, J. Related Collections Neuroanesthesia Pharmacology

---

NEUROSURGICAL ANESTHESIA

Dexmedetomidine-Induced Sedation in Volunteers Decreases Regional and Global Cerebral Blood Flow

Richard C. Prielipp, MD FCCM^*, Michael H. Wall, MD^*, Joseph R. Tobin, MD FCCM^*, Leanne Groban, MD^*, Mark A. Cannon, MD^*, Frederic H. Fahey, DSc, H. Donald Gage, PhD, David A. Stump, PhD^*, Robert L. James, MS^*, Judy Bennett, RN^*, and John Butterworth, MD^*

Departments of *Anesthesiology (Sections of Critical Care and Cardiothoracic Anesthesiology) and Radiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina

Address correspondence and reprint requests to Dr. Prielipp, Department of Anesthesiology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157-1009. Address e-mail to prielipp{at}wfubmc.edu

Dexmedetomidine is a selective ₂-agonist approved for sedation of critically ill patients. There is little information on the effects of dexmedetomidine on cerebral blood flow (CBF) or intracranial hemodynamics, despite considerable other pharmacodynamic data. We hypothesized that therapeutic doses of dexmedetomidine would decrease CBF. Therefore, nine supine volunteers, aged 24–48 yr, were infused with a 1 µg/kg IV loading dose of dexmedetomidine, followed by an infusion of 0.2 µg · kg^-1 · h^-1 (LOW DEX) and 0.6 µg · kg^-1 · h^-1 (HIGH DEX). Hemodynamic and CBF (via positron emission tomography) measurements were determined at each experimental time point. Dexmedetomidine decreased both cardiac output and heart rate during and 30 min after drug administration. Blood pressure decreased from 12% to 16% during and after the dexmedetomidine administration. Global CBF was decreased significantly from baseline (91 mL · 100 g^-1 · min^-1 [95% confidence interval, 72–114] to 64 mL · 100 g^-1 · min^-1 [51–81] LOW DEX and 61 mL · 100 g^-1 · min^-1 [48–76] HIGH DEX). This decrease in CBF remained constant for at least 30 min after the dexmedetomidine infusion was discontinued, despite the plasma dexmedetomidine concentration decreasing 40% during this same time period (628 pg/mL [524–732] to 380 pg/mL [253–507]).

IMPLICATIONS: Dexmedetomidine-induced sedation decreased cerebral blood flow (CBF) by 33%, which could be due to direct ₂-receptor cerebral smooth muscle vasoconstriction or to compensatory CBF changes caused by dexmedetomidine-induced decreases in the cerebral metabolic rate.

This article has been cited by other articles:

				J. D. Tobias Bradycardia During Dexmedetomidine and Therapeutic Hypothermia J Intensive Care Med, November 1, 2008; 23(6): 403 - 408. [Abstract] [PDF]

				M. Kumagai, T. Horiguchi, T. Nishikawa, Y. Masaki, and Y. Tobe Intravenous Dexmedetomidine Decreases Lung Permeability Induced by Intracranial Hypertension in Rats Anesth. Analg., August 1, 2008; 107(2): 643 - 647. [Abstract] [Full Text] [PDF]

				V. Bonhomme, P. Maquet, C. Phillips, A. Plenevaux, P. Hans, A. Luxen, M. Lamy, and S. Laureys The Effect of Clonidine Infusion on Distribution of Regional Cerebral Blood Flow in Volunteers Anesth. Analg., March 1, 2008; 106(3): 899 - 909. [Abstract] [Full Text] [PDF]

				Y. Ogawa, K.-i. Iwasaki, K. Aoki, S. Shibata, J. Kato, and S. Ogawa Central Hypervolemia with Hemodilution Impairs Dynamic Cerebral Autoregulation Anesth. Analg., November 1, 2007; 105(5): 1389 - 1396. [Abstract] [Full Text] [PDF]

				A. T Gerlach and J. F Dasta Dexmedetomidine: An Updated Review Ann. Pharmacother., February 1, 2007; 41(2): 245 - 252. [Abstract] [Full Text] [PDF]

				P. E. Tanskanen, J. V. Kytta, T. T. Randell, and R. E. Aantaa Dexmedetomidine as an anaesthetic adjuvant in patients undergoing intracranial tumour surgery: a double-blind, randomized and placebo-controlled study Br. J. Anaesth., November 1, 2006; 97(5): 658 - 665. [Abstract] [Full Text] [PDF]

				A. Bekker, M. Gold, R. Ahmed, J. Kim, C. Rockman, G. Jacobovitz, T. Riles, and G. Fisch Dexmedetomidine Does Not Increase the Incidence of Intracarotid Shunting in Patients Undergoing Awake Carotid Endarterectomy Anesth. Analg., October 1, 2006; 103(4): 955 - 958. [Abstract] [Full Text] [PDF]

				C. E. Schneemilch, H. Bachmann, A. Ulrich, R. Elwert, Z. Halloul, and T. Hachenberg Clonidine decreases stress response in patients undergoing carotid endarterectomy under regional anesthesia: a prospective, randomized, double-blinded, placebo-controlled study. Anesth. Analg., August 1, 2006; 103(2): 297 - 302, table of contents. [Abstract] [Full Text] [PDF]

Anesthesia & Analgesia® is published for the International Anesthesia Research Society® by Lippincott Williams & Wilkins with the assistance of Stanford University Libraries' HighWire Press®. Copyright 2006 by the International Anesthesia Research Society. Online ISSN: 1526-7598   Print ISSN: 0003-2999