Comparative study of epidural fentanyl and fentanyl plus magnesium for post-operative analgesia

Dr. Uthkala Bhaskar Hegde; Dr. P. Murali Mohan; Dr. R. Ajay Babu

Volume : VIII, Issue : XII, December - 2018

Comparative study of epidural fentanyl and fentanyl plus magnesium for post-operative analgesia

Dr. Uthkala Bhaskar Hegde, Dr. P. Murali Mohan, Dr. R. Ajay Babu

Abstract :

Background: Magnesium has antinociceptive effects in animal and human models of pain. It is found that the addition of magnesium to postoperative epidural infusion of fentanyl may decrease the need for fentanyl. We undertook a study to compare the duration of postoperative analgesia after epidural Fentanyl and epidural Fentanyl plus magnesium administered postoperatively, along with side effects.

Materials and Methods: 100 patients undergoing elective lower limb surgeries were randomized into one of the two groups with 50 patients in each group. Combined Spinal Epidural Anesthesia was used for all patients. Spinal anesthesia with 2.5 cc of 0.5% hyperbaric bupivacaine was given. When sensory blockade regressed to L1, patients were given either 50μg of Fentanyl (diluted to 6cc with normal saline, Group F) or 50μg of Fentanyl plus 50 mg Magnesium (diluted to 6cc with normal saline, Group FM). Parameters like blood pressure, pulse rate, respiratory rate and oxygen saturation were monitored, and other side effects were noted. Data were analysed by using Student t test and Chi–square/ Fisher Exact tests.

Results: There was significant difference in duration of analgesia between Group F (107 min) and Group FM (143 min). Hemodynamic parameters were stable in both the groups with minimal side effects.

Conclusion: Co–administration of magnesium with fentanyl for postoperative epidural analgesia results in prolongation of fentanyl analgesia without significant side–effects.