COMPARATIVE EVALUATION OF EPIDURAL MORPHINE, BUTORPHANOL & TRAMADOL FOR POST OPERATIVE PAIN RELIEF IN LOWER ABDOMINAL SURGERIES

Abstract

Background: Neuraxial blockade is the preferred technique over general anesthesia for most of the
lower abdominal surgeries. Effective post operative analgesia can be achieved by epidural anesthesia.
Depositing opiods in the epidural space helps in extending the postoperative analgesic duration. We want to evaluate the
effectiveness of Morphine, Butorphanol and Tramadol for the post operative period in combined spinal & epidural anesthesia.
Study design: This study was double blind randomised controlled study carried out on 75 patients undergoing herniorrhaphy,
in three groups of 25 each . The patients were randomly allocated into three groups. Group 'M' was taken as Morphine study
group, Group 'B' as Butorphanol study group and Group 'T' as Tramadol study group. L2-L3 interspace was identied and using
a 18 gauge combined spinal and epidural needle, epidural space was identied after which a long spinal needle (27G) is
inserted into sub arachnoid space, about 0.5% hyperbaric bupivacaine 15mg was injected. Then the epidural catheter is
inserted in the usual manner and kept 3 to 4 cms into the epidural space. At the end of surgery in group 'M' (morphine group) 50
mcg / kg of morphine in 10ml saline was injected through the epidural catheter. In the Group 'B' (butorphanol group) 40 mcg/ kg
of butorphanol in 10 ml saline was injected through the epidural catheter. In group 'T' (tramadol group), 1.5mg / kg of Tramadol
in 10 mg saline was injected through the epidural catheter and the catheter was removed in all the three groups. Time of
epidural opioid injection was noted. The level of consciousness was assessed every hour and graded according to the sedation
score. The pain relief is graded as VAPS and was assessed every hour and the total duration of post operative analgesia was
taken as the period from the time of giving epidural drugs till the patients rst requirement of rescue analgesic. Patients were
observed for any side effects like respiratory depression, nausea, vomiting, urinary retention, hypotension, pruritus, headache
for 24 hours. Kruskal – Wallis 'one way analysis of variance test” was performed to nd out the level of signicance in the
duration of analgesia, quality of analgesia, sedation between the three study groups.
Results: Morphine produces excellent post operative analgesia for a duration of 14-16 hours compared to butorphanol with a
duration of 7-9 hours, and tramadol with a duration of 4-6 hours. The onset of action of morphine was delayed by 60-90 minutes
while butorphanol and tramadol had an earlier onset of pain relief with in 5-10 minutes. There was no correlation between
sedation score and quality of analgesia. Morphine in these doses epidurally does not produce respiratory depression and
butorphanol which had ceiling effect does not produce the same while no such respiratory depression occurred in tramadol.
The incidence of vomiting is high with tramadol group 40% while 20% 20% each in butorphanol and morphine. Hence routine
use of antiemetics is advisable after epidural opioids. The incidence of urinary retention is 28% with morphine while no such
events occurred in other two groups.
Conclusion: It has been found out by this study that Morphine epidurally provides excellent long lasting pain relief compared
to butrophanol and tramadol. Morphine, the queen of opioids with respect to quality and duration of pain relief cannot be
compared with any other opioids. Hence it remains the gold standard opioid for pot operative analgesia epidurally.