Sub-hypnotic Dose of Propofol as Antiemetic Prophylaxis Attenuates Intrathecal Morphine-induced Postoperative Nausea and Vomiting, and Pruritus in Parturient Undergoing Cesarean Section

A Randomized Control Trial

Sylvanus Kampo; Alfred Parker Afful; Shiraj Mohammed; Michael Ntim; Alexis D. B. Buunaaim; Thomas Winsum Anabah


BMC Anesthesiol. 2019;19(177) 

In This Article


Cesarean section is among the most commonly performed surgeries in women, and it is associated with a more intense postoperative pain compared to the post-vaginal delivery pain.[1] Excellent postoperative analgesia is very crucial in providing maternal comfort, improving breastfeeding, improving mother-child bonding, early ambulation, early discharge, and enhancing patient satisfaction.[2] The use of spinal anesthesia for cesarean section provides an avenue for rendering better postoperative analgesia with neuraxial opioids.[1] Intrathecal morphine provides excellent postoperative analgesia. The current practice of using spinal anesthesia with morphine for parturient presenting for elective cesarean delivery in some hospitals has received mixed reactions from both parturient and staff. Although the addition of intrathecal morphine to bupivacaine offers excellent postoperative analgesia which covers for about 12 to 24 h, some fraction of parturients commonly experiences dose-dependent PONV and pruritus.[3]

PONV is an unpleasant condition, often underestimated side effect of anesthesia and surgery.[4] Despite the increasing fear of pain after surgery, patients still consider PONV to be a significant concern or complication of anesthesia.[5] When questioned about issues of concern, 22% of 800 patients in a study gave PONV the highest level of concern compared with 34% for postoperative pain and 24% for waking up during surgery.[6] Gan et al.[7] reported that most patients associated value to the avoidance of PONV and were willing to pay between the US $56 and the US $100 for a completely effective antiemetic. Due to its medical, surgical, patient and anesthetic etiological factors, its incidence is estimated to be 40 to 60% of all surgical interventions and patient population of which, 0.18% is resistant to PONV.[8] The intense efforts accompanying PONV increases the risk of aspiration pneumonitis, wound dehiscence, bleeding, hypertension, and increased intracranial pressure.[9] It also leads to higher consumption of calories, requires additional postoperative monitoring, and delayed discharge leading to a higher cost of care.[10] Other morbidities synonymous with PONV also includes; dehydration, electrolyte disturbance, interference with nutrition and, more rarely, esophageal rupture.[11]

Prophylaxis with antiemetic has been shown to reduce the incidence of PONV in surgical procedures by 15–30% (absolute risk reduction).[12] Numerous antiemetic has been studied for the prevention of PONV with varying degrees of success.[13] The efficacy of metoclopramide as an antiemetic is undoubted. Propofol anesthesia is known to have a low emetic score, and its antiemetic properties have been investigated. While it was found to be effective by some studies, the contrary was reported in some other studies.[8] Series of clinical trials have also reported that, at a sub-hypnotic dose, propofol is equally effective in reducing the incidence of not only PONV but also pruritus following intrathecal morphine.[14] Although routine PONV prophylaxis seems appropriate, the choice of antiemetic agents is wide, whereas some are too expensive in our setting for regular use. This study, therefore, aimed to ascertain the antiemetic effect, as well as reducing pruritus by a sub-hypnotic dose of propofol and compare its effect with metoclopramide among parturients receiving neuraxial morphine for cesarean section.