Utilization of Very Low Calorie Diet in Obese General Surgery Patients

Study Overview
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Brief Summary
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The investigators are studying the use of a two-week very low calorie diet (VLCD) in obese general surgery patients in a randomized single-blinded trial. The investigators hypothesize that the VLCD will positively impact the perceived surgical difficulty, operative time, hospital length of stay and 30-day complications. Additionally, the investigators anticipate reduced perioperative blood glucose levels and a reduced need for perioperative insulin administration.

Detailed Description
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The investigators' objective for this project is to determine the impact of a preoperative VLCD on outcomes for patients undergoing elective general surgery. Included are patients who are obese, BMI >30, and scheduled by a Christiana Care-employed general surgeon for elective general surgery. Eligible patients are those scheduled for elective cholecystectomy, ventral or incisional hernia, umbilical hernia, and inguinal hernia surgery. The investigators will also be determining the feasibility of introducing a preoperative VLCD for patients undergoing elective general surgery in a Community Hospital setting.

Official Title
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Utilization of Very Low Calorie Diet in Obese General Surgery Patients

Conditions
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Morbid Obesity

Intervention / Treatment
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* Dietary Supplement: Very low calorie diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients who are obese, BMI >30, and scheduled by a Christiana Care-employed general surgeon for elective general surgery. Patients between the ages of 18 and 65. Patients scheduled for elective cholecystectomy, ventral or incisional hernia, umbilical hernia, and inguinal hernia surgery. Exclusion Criteria: Patients will be excluded from the study if they have any of the following: Recent myocardial infarction (3-6 months). History of cerebral vascular accident (stroke). Diabetes mellitus with a history of severe ketoacidosis. Patients on SGLT2 inhibitors (glifozins) without insulin Chronic use of steroids, greater than 20mg daily. Bleeding peptic ulcer (unless there is radiological evidence of healing 6 months prior to entry). A psychiatric history that includes suicide attempts and anyone taking psychotropic drugs, including lithium carbonate. Active thrombophlebitis (or any other condition where decreased blood volume would put the patient at risk). In addition, patients who are pregnant are excluded. If status is unknown, a pregnancy test will be required prior to the start of the VLCD.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: The patient will be randomized into the treatment or control arm by the research team. If they are randomized into the treatment arm, they will be prescribed with a 2-week VLCD that will begin 2 weeks prior to the scheduled elective surgery.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Very Low Calorie Diet<br>If they are randomized into the treatment arm, they will be prescribed with a 2-week VLCD that will begin 2 weeks prior to the scheduled elective surgery. Patients will be required to pay for the meal replacements. | Dietary Supplement: Very low calorie diet<br>* The VLCD is a prescribed diet with well-balanced macro and micronutrients. It is intended for significant weight loss in a short period of time, is intended only for the extremely obese, and must be completed under the supervision of a trained physician.<br>|
| No Intervention: Standard Preop Diet<br>The control group will continue a regular diet until the day before surgery. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction in Post Operative Complications | Pulmonary, cardiac and surgical complications using data collected from inpatient and outpatient charting | 30-days post operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Feasibility of the Study | Patient satisfaction and compliance based on patient surveys administered prior to discharge from the hospital | 2 weeks | 
| Effect on Perioperative BMI | Difference in pre operative and perioperative BMI, in kg/m^2 | 2 weeks | 
| Effect on blood glucose levels | Difference in pre operative and perioperative blood glucose levels | 2 weeks | 
| Effect on insulin administration | Difference in pre operative and perioperative insulin administration, in units | 2 weeks | 
| Effect on operative times | Comparative operative times, in minutes, between control and intervention | Day of surgery | 
| Effect on operative blood loss | Comparative operative blood loss, in milliliters, between control and intervention | Day of surgery | 
| Effect on surgeon perceived difficulty | Comparative surgeon perceived difficulty between control and intervention utilizing a surgeon and procedure specific survey | Day of surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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General surgery, Very low calorie diet