Post-operative Emesis and Pain Outcomes After Cesarean Delivery

Post-operative Emesis and Pain Outcomes After Cesarean Delivery (EPOC)

Approximately 20% women who undergo cesarean delivery would suffer from severe post-operative pain, which may further increase their risks from developing postpartum depression. Predictive factors such as pre-operative pain, age and anxiety could significantly contribute to post-operative nausea and vomiting (PONV) and pain in general surgery, however little information is available with regards to cesarean delivery. The investigators would investigate the risk factors of causing post-operative emesis after cesarean delivery, and to reaffirm that there is a positive correlation between pain on local anesthetic injection, presence of mechanical temporal summation (MTS) and post-Cesarean pain scores.

Previous studies demonstrated that pain scores upon local anesthetic injection is positively correlated to post-cesarean pain scores. Anxiety, anticipated post-operative pain score and anticipated medication need are also found to be promising risk factors to post-cesarean pain management.

The investigators would investigate the risk factors of causing post-cesarean emesis, and to reaffirm that there is a positive correlation between pain on local anesthetic injection, presence of mechanical temporal summation (MTS) and post-Cesarean pain scores. 470 parturients undergoing cesarean delivery and requiring regional anaesthesia will be recruited. Pain and anxiety assessment will be conducted via visual analogue scoring (VAS), MTS assessment and a series of questionnaires. After delivery, patients will be given appropriate analgesia, and pain score at movement will be recorded. Secondary outcomes include pain scores at rest, analgesia consumption, time-to-first-rescue analgesia, opioid-related side effects, patient satisfaction and postpartum depression. A separate 125 patients will be recruited to evaluate the feasibility and patient acceptability of the use of Headspace, a mindfulness mobile application during the pre- and postnatal period to improve the maternal outcomes (emesis, pain, anxiety, depression).

Inclusion Criteria:

• Pregnant and going to have caesarean delivery (36 weeks gestation or more; nulliparous and multiparous);
• Healthy or have mild medical problems that are well-controlled (American Society of Anesthesiologists physical status 1-2).

Exclusion Criteria:

• History of intravenous drug or opioid abuse;
• Previous history of chronic pain syndrome;
• Emergency cesarean section;
• Undergo general anaesthesia during cesarean delivery;
• Non-English speaking.