Effect of Propofol on Postoperative Nausea and Vomiting.

Cesarean Section is one of the most commonly performed surgical procedures in the obstetric patients. Adequate intra and postoperative analgesia is very important in providing comfort to the mother, early breastfeeding, ambulation and discharge as well as enhancing patient satisfaction.Spinal anesthesia is widely accepted as the anesthesia of choice for cesarean section owing to its safety and speed. PONV is an unpleasant condition, often underestimated side effect of anesthesia and surgery, quite common in women undergoing spinal anesthesia for cesarean.It is one of the significant problems in Post Anaesthesia Care Units. The etiology of PONV is multifactorial with patient factors (gender, history of motion sickness, age), intra Op factors (type of anesthesia, surgery and opioid use) and post Op factors (pain, post Op opioid use) which are found to be associated with the PONV. Apfel simplified scoring is based on four independent factors including female gender, non-smoker, history of PONV or motion sickness and use of opioids. Each predictor is given a score of 1. A score of 0,1,2,3 or 4 predicts the chance of developing PONV as approximately 10%, 20%, 40% or 80%.

The intense efforts accompanying emesis increase the risk of complications such as wound dehiscence, bleeding, aspiration pneumonitis, dehydration, electrolyte imbalance and interference with nutrition. While it is difficult to completely avoid the occurrence of PONV, it can be markedly reduced using a multimodal non-opioid analgesia, total intravenous anesthesia and adequate prophylactic antiemetic premedication. Propofol has been reported to have anti-emetic effects at sub hypnotic dose as a bolus or a continuous infusion in susceptible individuals undergoing surgeries, though the exact mechanism of this effect is yet to be discovered.

In a research published in BMC Anesthesiology, the data indicates a significant difference in the incidence of PONV in control group (93.9%) and the study group (8.7%) with a single sub hypnotic dose of propofol administered 10-15 min before the end of surgery in parturients undergoing cesarean section under spinal anaesthesia.

Inclusion criteria

• Parturient aged between 18 - 50 years
• Elective Cesarean under spinal anesthesia
• Patients at increased risk of PONV based on Apfel score 2 or more
• ASA Class II
• Ability to give informed consent

Exclusion criteria

• Allergy to propofol
• ASA Class III and above
• Anti emetic drug administered 24 hrs prior to surgery