Intravenous dexamethasone combined with intrathecal atropine to prevent morphine-related nausea and vomiting after cesarean delivery: A randomized double-blinded study

ABSTRACT Background: Intrathecal morphine can be considered as a gold standard for analgesia following cesarean section (CS), which is not devoid of complications namely postoperative nausea and vomiting. We evaluated the antiemetic effect of intravenous dexamethasone combined with intrathecal atropine after CS. Methods: 120 parturient undergoing elective CS under spinal anesthesia were randomized into three groups. Dexamethasone group (D): Received intrathecal hyperbaric bupivacaine (0.5% in 2 ml) mixed with morphine (200 μg in 0.5 ml) and normal saline (0.5 ml as placebo) and intravenous (iv) dexamethasone (8 mg in 2 ml). Atropine group (A): Received hyperbaric bupivacaine (0.5% in 2 ml) mixed with morphine (200 μg in 0.5 ml) and atropine (100 μg in 0.5 ml), in addition to iv normal saline (2 ml as placebo). Dexamethasone and Atropine group (DA): Received intrathecally as group A, and iv dexamethasone (8 mg in 2 ml). Follow-up of both nausea and vomiting was done during the first 24 hours postoperatively. Results: Nausea was noticed in 7 patients (17.5%) in group D, 8 patients (20%) in group A, and one patient (2.5%) group DA, with significant differences between DA and D (p = 0.025) and DA and A (p = 0.013). Regarding vomiting, there were 5 patients (12.5%) in group D, 4 patients (10%) in group A only, with significant differences between DA and D (p = 0.021) and DA and A (p = 0.041). Conclusions: Combination of intravenous dexamethasone and intrathecal atropine has additive antiemetic effect after spinal anesthesia for cesarean delivery using bupivacaine and morphine