Effect of adding nalbuphine to intrathecal bupivacaine with morphine on postoperative nausea and vomiting and pruritus after elective cesarean delivery: a randomized double blinded study.

BACKGROUND

The use of intrathecal morphine may result in serious side effects in parturients undergoing cesarean delivery. Nalbuphine, is a mu receptor antagonist and a ĸappa receptor agonist. Combinations of opioid agonist and agonist antagonist can decrease the incidence of opioid related side effects. We aimed to investigate the effect of adding nalbuphine, to intrathecal morphine on postoperative nausea and vomiting and pruritus after a cesarean delivery.

METHODS

Eighty parturient undergoing elective cesarean delivery under spinal anesthesia were randomized into two similar groups. Group 1: received 10 mg of 0.5% hyperbaric bupivacaine with 0.2 mg morphine. Group 2: received as a group 1 plus 0.5 mg nalbuphine, with total volume 2.5 mL in both groups. Measurements: Data on the severity of nausea and vomiting were collected using a numerical rating scale and visual analogue scale was used to quantify pruritus. Onset and duration of sensory blockade, Visual Analog Scale for pain, the first time to ask for rescue analgesia and total rescue analgesic consumption were recorded.

RESULTS

Nausea and vomiting and pruritus severity scores and number of patients developed nausea and vomiting and pruritus were significantly lower (P<0.001) in group 2. Onset and duration of sensory block, time to first request for rescue analgesia, Visual Analog Scale for pain and paracetamol consumption showed no statistically differences between both groups (P>0.05).

CONCLUSIONS

We concluded that the addition of nalbuphine to intrathecal bupivacaine plus morphine significantly reduced the incidence and severity of postoperative nausea and vomiting and pruritus without affecting analgesic potency.