PReoperative Very Low Energy Diets for Obese PAtients Undergoing Non-bariatric Surgery

Participation Requirements

• Sex:

  ALL

• Eligible Ages:

  18 and up

Participation Criteria

Inclusion Criteria:

* Older than 18 years of age
* BMI of greater than 30 kg/m2
* Undergoing major elective non-bariatric surgery. Major surgery is defined as any operation performed under general anesthesia requiring a skin incision extending beyond the subcutaneous tissue.

Exclusion Criteria:

* Undergoing bariatric surgery
* Undergoing neurologic surgery
* Undergoing urgent or emergent surgery
* Recently diagnosed myocardial infarction or unstable angina (i.e., within past six months)
* Diagnosed moderate-to-severe renal dysfunction (i.e., eGFR less than 30mL/min/1.73m2)
* Diagnosed severe liver dysfunction (i.e., cirrhosis, portal hypertension, hepatic encephalopathy, hepatorenal syndrome)
* Recently diagnosed alcohol or drug use disorders (i.e., excessive use of substance within past six months)
* Experienced a recent episode of gout (i.e., within past six months)
* Medical history of porphyria; (10) Known allergy to any Optifast ingredient
* Enrolled in other prospective studies with similar interventions and/or outcomes. Co-enrollment may be deemed appropriate if the steering committees of the respective trials review the details of participation.
* Pregnant or breastfeeding women
* Patients unable to provide informed consent.