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Systemic ondansetron antagonizes the sensory block produced by intrathecal lidocaine

Argyro Fassoulaki1, A Melemeni, Marianna Zotou

  • 1*Department of Anesthesiology, Aretaieio Hospital, Medical School, University of Athens; †Department of Anesthesiology, St Savas Hospital, Athens, Greece; and ‡Department of Anesthesia, Medical College of Wisconsin, Milwaukee.

Anesthesia and Analgesia
|May 28, 2005
PubMed

Insights

Ondansetron was found to reduce the sensory block effect of lidocaine spinal anesthesia in male patients undergoing transurethral surgery. This finding suggests ondansetron antagonizes lidocaine

Area of Science:

  • Anesthesiology
  • Pharmacology

Background:

  • Subarachnoid anesthesia using lidocaine is common for transurethral surgery.
  • Understanding drug interactions is crucial for optimizing anesthetic techniques.

Purpose of the Study:

  • To investigate the effect of ondansetron on lidocaine-induced subarachnoid block.
  • To assess sensory and motor block characteristics with ondansetron co-administration.

Main Methods:

  • Prospective randomized, double-blind study involving 54 male patients.
  • Patients received either oral and IV ondansetron or placebo before intrathecal lidocaine.
  • Sensory and motor block levels were assessed at specific time points post-injection.

Main Results:

  • Ondansetron group showed significant differences in sensory block values over time (P = 0.048).
  • Sensory block level at 30 minutes post-injection differed significantly between groups (T12 vs. L1, P = 0.019).
  • No significant difference in motor block was observed between the ondansetron and placebo groups.

Conclusions:

  • Ondansetron antagonizes the sensory block produced by lidocaine subarachnoid anesthesia.
  • Ondansetron may alter the efficacy of lidocaine for spinal anesthesia.

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