Efficacy of Serratus Anterior Plane Block Using Bupivacaine/ Magnesium Sulfate Versus Bupivacaine/ Nalbuphine for Mastectomy: A Randomized, Double-Blinded Comparative Study

BACKGROUND: Mastectomy is a common surgical procedure associated with intra and postoperative pain if untreated adequately will lead to chronic pain. OBJECTIVES: This study aimed to evaluate the efficacy of serratus anterior plane block using bupivacaine/magnesium sulfate versus bupivacaine/ nalbuphine for mastectomy. METHODS: 40 ASA I and II female patients age 25 - 60 years underwent breast cancer surgery received the block before induction of general anesthesia were divided into two groups GBM (n = 20): (bupivacaine/magnesium sulphate): received bupivacaine 30 mL 0.25% and 500 mg magnesium sulphate, GBN (n = 20): (bupivacaine/nalbuphine): received bupivacaine 30 mL 0.25% and nalbuphine 0.2 mg/kg. The following parameters were recorded: The sensory block, motor block, postoperative heart rate, noninvasive mean blood pressure: at 1, 6, 12, 24 h, postoperative time to first request of analgesics (hours), VAS at rest and movement at 1, 6, 12, 24 h, postoperative analgesic requirements (pethidine mg/24 h). RESULTS: The sensory block was statistically significantly lower in the GBM group than the GBN group at 24 hours postoperatively. The Medical Research Council scale was statistically significantly lower in the GBN group than the GBM group at 24 hours postoperatively. Postoperative time to first request of analgesics (hours) was statistically significantly longer in the GBN group than the GBM group, VAS at rest was statistically significantly lower in the GBN group than GBM group at 6th and 24th hours, VAS at movement showed no statistically significant differences between the two groups. Intraoperative fentanyl and postoperative analgesic requirements (pethidine mg/24 h) showed no statistically significant differences between the two groups. CONCLUSIONS: Serratus anterior plane block using bupivacaine/nalbuphine provided effective postoperative analgesia, reduced postoperative pain than bupivacaine/magnesium sulfate in a mastectomy.