The prevalence of obesity has increased dramatically recently. Obesity is a pro-inflammatory state which leads to chronic low grade inflammation having different systemic effects. This may make obesity an independent risk factor for severe acute postoperative pain. No prospective studies have been conducted to specifically evaluate the quality of recovery after caesarean delivery for women with morbid obesity when compared to non-obese parturients. In addition, while there is biological plausibility to infer worse pain scores in parturients with obesity, the magnitude of this difference is unknown and information guiding adjustments in pain management are lacking.

The prevalence of obesity has increased dramatically over the recent past in both developed and developing countries.

Obesity is a pro-inflammatory state which leads to chronic low grade inflammation. It has been well studied that this very inflammation and oxidative stress is responsible for cardiovascular pathologies seen in these patients. As a result, the post-operative period is characterized by a phase of prolonged systemic inflammatory response, which makes obesity an independent risk factor for severe acute pain. As a matter of fact, an extreme rise in IL-6 in patients with obesity has been demonstrated post-operatively.

In addition, adipose tissue acts as an endocrine organ by releasing a number of other pro-inflammatory proteins. Cytokines are known to promote various metabolic, hemodynamic and immunologic changes post-surgery, and in the setting of exaggerated inflammatory response can lead to increased pain and hemodynamic instability.

Very few studies have evaluated the recovery experience of patients with obesity in the acute postoperative period. Patients with obesity undergoing general abdominal surgery have been shown to have worse surgical outcomes, increased complication rates, and increased analgesic requirements.7 However, in spine surgery, there have been conflicting evidence supporting a difference in pain scores in patients with obesity. Despite there being no clear guidelines on post-operative pain control between these two groups, providers reported prescribing less opioid analgesics post-operatively to patients with obesity when compared to patients not suffering from this condition.

The Obstetric Quality of Recovery Score (ObsQoR) was initially developed and validated as a measure of patient reported outcome after caesarean delivery. It started as an 11-item questionnaire (ObsQoR-11), which was further simplified to 10-items (ObsQoR-10) following patient feedback where moderate and severe pain questions were combined into a single item. This tool measures pain, nausea or vomiting, dizziness, shivering, comfort, mobility, ability to hold and feed the baby, personal hygiene maintenance, and feeling in control, to provide a global inpatient postpartum quality of recovery score out of 100. A systematic review assessing measurement properties of available patient-reported outcome measures using COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) methodology, recommended ObsQoR as the best available instrument to measure functional recovery following caesarean delivery.

No prospective studies have been conducted to specifically evaluate the quality of recovery after caesarean delivery for women with morbid obesity when compared to non-obese parturients. In addition, while there is biological plausibility to infer worse pain scores in parturients with obesity, the magnitude of this difference is unknown and information guiding adjustments in pain management are lacking.

The investigators hypothesize that parturients with Class 3 obesity experience impaired quality of recovery scores after elective cesarean delivery as measured by the ObsQoR-10 when compared to non-obese parturients.

Inclusion Criteria:

• Age > 18 years
• Term pregnancy (> 37 weeks gestational age)
• Elective caesarean delivery
• BMI >40 (Study Group) or BMI <30 (Control Group)
• ASA<=3

Exclusion Criteria:

• Chronic pain
• History of opioid use during pregnancy.
• History of substance abuse disorder during pregnancy.
• Contraindication to neuraxial opioids, acetaminophen and/or NSAIDs
• Language barrier
• Allergy to Opioids or NSAIDS
• Intra-operative conversion to general anesthesia
• Maternal Admission to ICU.
• Neonatal admission to NICU.

Female subjects currently pregnant undergoing elective cesarean delivery

Pregnant women meeting inclusion and exclusion criteria who are scheduled to have their Caesarean Section at Victoria Hospital, London Health Sciences Centre will be consented for participation in the study. Patients will be recruited from obstetrical and preadmission clinics at LHSC Victoria Hospital, as well as at admission for Caesarean Section to the Obstetrical Care Unit. Patients will be recruited only when inclusion criteria are fulfilled, in the absence of exclusion criteria, and after informed consent has been obtained.