Bupivacaine ineffective for reducing postoperative laparoscopic tubal ligation pain
MedWire News: Study findings show that local injection of bupivacaine in the trocar ports does not reduce the level of postoperative pain in patients undergoing tubal ligation (TL) with electrocoagulation.
Ricardo Savaris (Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil) and co-authors say that clinical experiences with ropivacaine and bupivacaine in TL suggest that that bupivacaine should be effective in reducing postoperative pain. However, no previous studies have supported the use of bupivacaine 0.5 percent in trocar ports of TL with electrocoagulation.
To investigate, the team randomly assigned patients scheduled for laparoscopic TL to receive bupivacaine 0.5 percent (n = 29) or placebo (n = 24) injection as a local anesthetic agent after anesthetic induction at the site of the trocar.
No difference in pain assessment was seen at 15, 30, 120 min, and 14 hours postoperatively, as measured by the verbal analogue scale, between patients receiving bupivacaine and those receiving placebo.
Furthermore, no significant difference in pain scores were seen between the groups after administration of postoperative pain medications including morphine, dipyrone, and sodium diclofenac.
The researchers say that a possible explanation for the findings may be related to the mechanism of pain after laparoscopy: “Rapid distension of the peritoneum, traumatic traction of the nerves and release of inflammatory mediators are plausible pathways that are not addressed by local infiltration of bupivacaine in the abdominal wall, more specifically in laparoscopic ports.”
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By Ingrid Grasmo