Duration of cutaneous analgesia induced by bupivacaine and ketamine in female Wistar rats; role of epinephrine
No Thumbnail Available
Date
2025
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier BV
Abstract
ketamine on rats’ cutaneous trunci muscle re昀氀ex (CTMR) and the effect of epinephrine on the
duration of analgesia.
Methods: Fifteen rats were randomly selected into three groups of 昀椀ve rats each. Each rat served as
its own control with the right and left thoracolumbar regions being the experimental and control
sites respectively. Rats in the 昀椀rst group (group A) were administered Bupivacaine alone, Group B
rats were given Ketamine alone while Group C rats were in昀椀ltrated with a combination of
Bupivacaine and Ketamine. The experiment was repeated seven days after with the addition of
epinephrine to all the 3 categories of in昀椀ltrate. 0.6 ml total volume of drugs in each group was
injected subcutaneously following which CTMR was stimulated via forceps bite on the injection
and control sites alternately. The duration of induced analgesia (period of negative responses) in
each group was recorded.
Results: The result showed a statistically signi昀椀cant difference (P < 0.05) in the duration of
analgesia among the three groups. Bupivacaine and ketamine injections individually produced
analgesia of 160 min and 120 min, respectively while a combination of both drugs acted for less
duration. The duration of analgesia was further prolonged in all three groups following the
addition of epinephrine.
Conclusion: Bupivacaine and ketamine have a combined analgesic effect that is permissive on one
another rather than additive and these effects are prolonged by concurrent administration with
epinephrine due to its local vasoconstrictive effect.
Description
Keywords
Ketamine Cutaneous re昀氀ex Epinephrine Analgesia