Article Text

Download PDFPDF
Effect of Vasoconstrictor Agents on the Duration of Action of Intrathecal Tetracaine, Bupivacaine and Lidocaine in the Dog
  1. Hal S. Feldman, BSc* and
  2. Benjamin G. Covino, PhD, MD
  1. From the Department of Anesthesia, Brigham and Women's Hospital, Boston, Massachusetts
  2. *Associate Pharmacologist, Department of Anesthesia Research Laboratories, Brigham and Women's Hospital, Boston, MA, and Research Associate, Harvard Medical School, Boston, Massachusetts.
  3. Professor of Anesthesia, Harvard Medical School and Chairman, Department of Anesthesia, Brigham and Women's Hospital, Boston, Massachusetts.


Both epinephrine and phenylephrine are capable of prolonging the duration of anesthesia when added to solutions of tetracaine intended for intrathecal use. Conflicting data exist concerning the relative efficacy of vasoconstrictor agents added to lidocaine and bupivacaine solutions intended for intrathecal use. The present investigation was initiated to study the comparative efficacy of epinephrine and phenylephrine in combination with tetracaine, lidocaine, and bupivacaine employing a model for spinal anesthesia in the dog. The results indicate that epinephrine and phenylephrine are capable of significantly prolonging the duration of motor blockade induced by tetracaine in the dog. When compared to plain solutions, no significant prolongation of motor blockade was observed following intrathecal administration of either lidocaine or bupivacaine with epinephrine and phenylephrine.

  • Anesthesia
  • Spinal
  • Anesthetics—Bupivacaine
  • Lidocaine
  • Tetracaine
  • Vasoconstrictors—Epinephrine
  • Phenylephrine

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.