Evaluation of Postoperative Anti-nociceptive Efficacy of Intrathecal Dexketoprofen in Rats

Some studies have suggested that the intrathecal use of cyclooxygenase enzyme inhibitors provides an anti-nociceptive effect. Therefore, the occurrence of side effects seen in systemic usage can be eliminated.

The primary objective of this experimental, randomized, controlled trial was to test the hypothesis asserting that intrathecal dexketoprofen trometamol would demonstrate an analgesic effect during postoperative period.

Animal experimentation.

Forty rats were randomized into 4 groups 7 days after intrathecal catheterization; the following drugs were given through catheter lumens: Group Lidocaine (Group L): Lidocaine 20 μg; Group Lidocaine-Morphine (Group LM): Lidocaine 20 μg and morphine 0.5 μgr; Group Lidocaine-Dexketoprofen (Group LD): Lidocaine 20 μg and dexketoprofen trometamol 100 μg; and Group Dexketoprofen (Group D): Dexketoprofen trometamol 100 μg. Paw incision was achieved under ether inhalation. To measure analgesic potential, hot plate and tail immersion tests were used as nociceptive tests during the postoperative period.

The mean reaction times detected in groups during hot plate and tail immersion tests were shortest in Group L at 15, 30, 45, 60, 75, 90, 105, and 120 minutes after start of surgery (p<0.01, all others). In the groups using dexketoprofen, as in the morphine group, longer reaction times were detected than in the lidocaine group at all measurement times except 120 minutes (p<0.01).

Intrathecal dexketoprofen in the optimal perioperative pain management is effective, and can be administered as an adjuvant in clinics after neurotoxicity studies in animals, and effective dose studies in volunteers.