eP149 - Preoperative Very Low Energy Diets for Patients with Obesity Undergoing Colorectal Surgery: A Retrospective Cohort Study

Sunday, June 2, 2024

8:54 AM – 8:59 AM ET, USA

Location: Baltimore Convention Center, Room 318-320

ePoster Presenter(s)

Tyler McKechnie, MD, MSc (he/him/his)

Resident Physician
McMaster University
McMaster University
Hamilton, ON, Canada

All of the relevant financial relationships listed below have been mitigated.
This individual has no financial relationships with ineligible companies.

Author(s)

Tania Kazi, BScH

McMaster University
McMaster University
Oakville, ON, Canada

All of the relevant financial relationships listed below have been mitigated.
This individual has no financial relationships with ineligible companies.
VS

Victoria Shi, MA

Medical Student
McMaster University
Waterloo, Ontario, Canada

Disclosure information not submitted.
SG

Shan Grewal, n/a

Medical Student
McMaster University
Hamilton, Ontario, Canada

Disclosure information not submitted.
AA

Ahmed Aldarraji, HBSc

Medical Student
McMaster University
Milton, Ontario, Canada

Disclosure information not submitted.
Kelly Brennan, MSc, MD

General surgery resident physician
Queen's University
Queen's University
Kingston, ON, Canada

All of the relevant financial relationships listed below have been mitigated.
This individual has no financial relationships with ineligible companies.
SP

Sunil Patel, MD

Associate Professor
Queens University
Kingston, Ontario, Canada

Disclosure information not submitted.
NA

Nalin Amin, MD, FRCS(C)

Associate Professor
McMaster University
Ancaster, Ontario, Canada

Disclosure information not submitted.
AD

Aristithes Doumouras, MD, MPH

Assistant Professor
McMaster University
Hamilton, Ontario, Canada

Disclosure information not submitted.
SP

Sameer Parpia, PhD

Associate Professor & Biostatistician
McMaster University
Hamilton, Ontario, Canada

Disclosure information not submitted.
MB

Mohit Bhandari, MD PhD FRCSC

Chair of the Department of Surgery
Department of Surgery, McMaster University
Hamilton, Ontario, Canada

Disclosure information not submitted.

Senior Author(s)

CE

Cagla Eskicioglu, MD, Msc, FRCSC

Associate Professor, Colon & Rectal Surgeon
Faculty of Health Sciences, McMaster University
Hamilton, Ontario, Canada

Disclosure information not submitted.

Purpose/Background: When implemented before bariatric surgery, very low energy diets (VLEDs) have been associated with decreased operative time, reduced surgeon perceived difficulty, and improved postoperative morbidity. Given these benefits, surgeons have adopted this practice for patients with obesity undergoing colorectal surgery. To investigate the impact of this practice, we designed a retrospective study comparing a cohort of patients managed after 2018 at our center who received preoperative VLED prior to elective colorectal surgery to a historical cohort of patients managed prior to 2018.Methods/Interventions: This is a single center, comparative retrospective cohort study. Patients 18 years of age or older with body mass indices (BMIs) of 30 kg/m2 or greater undergoing elective intra-abdominal colorectal surgery for benign or malignant disease were eligible for inclusion. Exclusion criteria included emergency and palliative surgery. Patients prior to January 1st, 2018 did not receive VLED and patients after January 1st, 2018 received VLED. Preoperative VLED consisted of Optifast 900 for two-to-four weeks before surgery. The primary outcome was 30-day postoperative morbidity. Postoperative morbidity was defined as any deviation from the expected clinical course within 30 days of the surgical date. Secondary outcomes included system-specific postoperative morbidity, length of stay (LOS), readmission, operative time, estimated blood loss, and intraoperative complications. Multivariable regressions were fit to determine the association between outcomes and VLED use. An a priori sample size calculation determined 83 patients per arm were required.Results/Outcomes: There were 89 patients in the VLED group (median age: 66 years IQR 58-72, mean BMI: 36.4kg/m2, 48.3% female) and 101 patients in the non-VLED group (median age: 68 years IQR 59-75, mean BMI: 33.2kg/m2, 44.6% female). Patients in the VLED group had significantly larger baseline BMIs (p < 0.01), otherwise there were no significant baseline differences. Most patients underwent surgery for colorectal neoplasia (VLED: 79.8%; Non-VLED: 72.9%, p=0.19). The most common operations across both groups were right hemicolectomy (VLED: 30.3%; Non-VLED: 35.7%, p=0.84) and low anterior resection (VLED: 29.2%; Non-VLED: 22.8%, p=0.31). Most operations were performed laparoscopically (VLED: 95.5%; Non-VLED: 91.1%, p=0.229). Multivariable regression demonstrated a 73% reduction in odds of postoperative morbidity in the VLED group (95%CI 0.14-0.55, p < 0.01). Infectious morbidity (OR 0.27, 95%CI 0.09-0.78, p=0.02), respiratory morbidity (OR 0.28, 95%CI 0.09-0.82, p=0.02), cardiovascular morbidity (OR 0.27, 95%CI 0.08-0.98, p=0.04), and wound complications (OR 0.18, 95%CI 0.05-0.59, p < 0.01) were significantly reduced in the VLED group. There were no differences in LOS (coef. -0.10 95%CI -0.30-0.09, p=0.29) or readmission (OR 0.36, 95%CI 0.10-1.26, p=0.11). The odds of intraoperative complication were reduced with VLED (OR 0.39, 95%CI 0.15-1.06, p=0.07). There were no differences in operative time (coef. -0.02, 95%CI -0.13-0.08, p=0.66) and estimated blood loss (coef. 0.23, 95%CI -0.12-0.58, p=0.20).Conclusion/

Discussion: This study suggests that the preoperative use of VLEDs for patients with obesity undergoing colorectal surgery may significantly reduce the risk of postoperative morbidity. Further prospective evaluation of preoperative VLEDs is warranted.