Prophylactic preoperative administration of oral gabapentin versus metoclopramide for prevention of opioid induced pruritis in spinal anesthesia.

Abstract Background Spinal opioids have become a mainstay of clinical pain management in labor, in perioperative care, and in chronic pain management. Spinal opioids are frequently co- administered with local anesthetics to provide analgesia requiring lower doses of each agent, thus minimizing most undesirable side effects. Most opioid-induced side effects such as nausea, vomiting, and respiratory depression are more commonly observed following systemic administration.8 By contrast, pruritus is more commonly observed following intrathecal or epidural administration, particularly in obstetric patients. Aim of the Work to compare the efficacy of gabapentin versus metoclopramide for prevention of intrathecal opioids induced pruritus. Patients and Methods This study is a double blinded prospective randomized controlled clinical trial. This study conducted at Ain Shams University Hospital. The period of the study is a 6 months. 62 adult patients undergoing elective operations under spinal anesthesia at Ain Shams University hospital. Results The demographic data (age, gender, and ASA physical status) was statistically non- significant. The mean age was 35.1 years old in Group G and 36.8 years old in Group M with a P value of 0.569. The female-to-male ratio was 63.1 % in Group G and 82.3% in Group M with a P value of 0.607. In Group G, 71 % were of ASA 1 physical status and 29 % of ASA 2 physical status while in Group M, 67.7% were of ASA 1 physical status and 32% of ASA 2 physical status with a P value of 0.783. The whole incidence of pruritus in the two groups was 31.5%, (48.8% in group G and 45.2% in group M). There is no statistically significant difference, with a p-value 0.799. As for the severity, both drugs showed reduction of VAS score from the first hour after intrathecal fentanyl injection. Gabapentin showed to be more potent in decreasing the severity of pruritus as 2 patients only needed rescue treatment compared to 5 patients from metoclopramide group (but insignificant difference with p value 0.341). The overall incidence of nausea was 17.7% (22.58 in Gabapentin group and 12.9% in metoclopramide group). As for the incidence of vomiting, the whole incidence was 11.29% (16.13% in Gabapentin group and 6.45% in metoclopramide group). There was no statistically significant difference with a p-value 0.118 for nausea and p-value 0.374 for vomtitng. Conclusion The results of the study showed that Gabapentin is as effective as Metoclopramide in prevention of opioid induced pruritus in spinal anesthesia. But, Gabepentin improved to be slightly more effective in reducing the severity of pruritus than Metoclopramide.