Preoperative Very Low-Calorie Diet Reduces Technical Difficulty During Laparoscopic Cholecystectomy in Obese Patients

The safety, tolerability and clinical impact of pre-operative very low-calorie diet prior to non-bariatric abdominal surgery: a systematic review

BACKGROUND

The use of pre-operative very low-calorie diets (VLCD) is established within bariatric and gallbladder surgery. However, their use in patients with high BMI and hepatic steatosis (HS) requiring upper abdominal procedures is unclear. This review aims to assess the safety, adherence, and outcomes of a pre-operative VLCD prior to non-bariatric elective surgery.

METHODS

A systematic search on PubMed MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL and AMED was performed to identify the included studies. Studies were included, if they administered a VLCD to patients undergoing non-bariatric elective surgery and reported on outcomes.

RESULTS

Eight studies were included in this review and all administered a VLCD through either dietician led diet plans or meal replacement shakes. The adherence to the VLCD was heterogeneously measured but was excellent overall with a good safety profile. The VLCD was able to significantly reduce HS and resulted in a less technically difficult operation with reduced intra-operative blood loss. There was no significant impact on intraoperative or early post-operative outcomes.

CONCLUSION

This review highlights that a VLCD can be administered safely during the pre-operative period and overall adherence is excellent, however heterogeneously measured. There was an overall positive impact on reducing hepatic steatosis, operative difficulty and intraoperative blood loss, however no significant impact on overall morbidity and mortality.

Evaluating the evidence for a liver shrinkage diet for obese patients prior to laparoscopic cholecystectomy: A systematic review and meta-analysis

BACKGROUND

The role of a very low-calorie diet (VLCD) before cholecystectomy in obese patients is unclear. This study evaluated whether VLCD could be used as a risk mitigation strategy for this high-risk patient cohort.

PATIENTS AND METHODS

A systematic review and meta-analysis was performed (PROSPERO ID CRD42022374610). The primary outcome was to determine the impact of pre-operative VLCD on the operative findings and ease of dissection during laparoscopic cholecystectomy (LC).

RESULTS

Two studies were included with a total of 84 patients. VLCD was associated with a significantly easier Calot's dissection (MD: -0.58 (95% confidence interval [CI] [ -1.03, -0.13], P = 0.01) and was associated with a significantly higher rate of pre-operative weight loss (MD; 2.92 (95% CI [2.23, 3.62], P = 0.00001).

CONCLUSIONS

The published evidence regarding VLCD before cholecystectomy in obese patients is limited. After acknowledging the limitations of the data, VLCD is associated with a significantly higher rate of weight loss preoperatively and directly impacts the ease of intraoperative dissection of Calot's triangle. Routine use of VLCD should be considered for all obese patients undergoing elective LC.

Elective Surgery in Adult Patients with Excess Weight: Can Preoperative Dietary Interventions Improve Surgical Outcomes? A Systematic Review

This systematic review summarises the literature regarding the impact of preoperative dietary interventions on non-bariatric surgery outcomes for patients with excess weight/obesity, a known risk factor for poor surgical outcomes. Four electronic databases were searched for non-bariatric surgery studies that evaluated the surgical outcomes of a preoperative diet that focused on weight/fat loss or improvement of liver steatosis. Meta-analysis was unfeasible due to the extreme heterogeneity of variables. Fourteen studies, including five randomised controlled trials, were selected. Laparoscopic cholecystectomy, hernia repair, and liver resection were most studied. Diet-induced weight loss ranged from 1.4 kg to 25 kg. Preoperative very low calorie diet (≤800 kcal) or low calorie diet (≤900 kcal) for one to three weeks resulted in: reduction in blood loss for two liver resection and one gastrectomy study (-27 to -411 mL, p < 0.05), and for laparoscopic cholecystectomy, reduction of six minutes in operating time (p < 0.05) and reduced difficulty of aspects of procedure (p < 0.05). There was no difference in length of stay (n = 7 studies). Preoperative ≤ 900 kcal diets for one to three weeks could improve surgical outcomes for laparoscopic cholecystectomy, liver resection, and gastrectomy. Multiple randomised controlled trials with common surgical outcomes are required to establish impact on other surgeries.

Preoperative weight loss in women with obesity in gynaecologic oncology: A retrospective study

To retrospectively review the efficacy of short term supervised medical weight loss for women with obesity, body mass index (BMI ≥40 kg/m² ) in gynaecologic oncology, and the associated perioperative and pathologic outcomes. A retrospective study of a dedicated preoperative weight loss clinic for gynaecologic oncology patients from March to December 2019. Statistical analysis was performed with McNemar's test for correlated proportions, Pearson's correlation tests for continuous variables, and paired t-tests to compare means. Generalized estimating equations (GEE) were used to determine the factors associated with weight loss over time. A P-value of <.05 was used for statistical significance. Review of cases up-graded after surgery was performed by a gynaecologic pathologist. There were a total of 49 women included in the study. The most common referral reason was endometrioid carcinoma or hyperplasia of the endometrium (77.6%). Mean initial weight was 130.2 kg, and corresponding mean BMI 48.1 kg/m² . Patients attended on average nine preoperative weight loss visits. A significant difference between initial weight and weight at surgery was demonstrated, from 129.6 to 118.0 kg (8.4% weight loss) (P < .0001). This difference persisted to their post-surgical visit, with an additional mean loss of 1.89 kg (9.4% weight loss) (P = .044). The majority (92.1%) of patients with endometrial pathology had surgical management, and of these 85.7% were minimally invasive. Preoperative weight loss is a feasible option in gynaecologic oncology patients. Greater understanding of clinical significance, follow-up, and ideal target population for this intervention is needed.

Preoperative weight loss program involving a 20-day very low-calorie diet for obesity before laparoscopic gastrectomy for gastric cancer

INTRODUCTION

The increased visceral fat in patients with obesity can increase the technical difficulty of surgery. This study was performed to evaluate a preoperative 20-day very low-calorie diet for obesity before laparoscopic gastrectomy for gastric cancer.

METHODS

This prospective single-center study involved patients with obesity who were planning to undergo laparoscopic gastrectomy for gastric cancer. Obesity was defined according to the Japanese criteria: BMI ≥25 kg/m² or waist circumference ≥85 cm in men and ≥90 cm in women. The patients underwent a preoperative 20-day very low-calorie diet and received nutritional counseling. Weight loss, body composition, visceral fat mass, and operative outcomes were evaluated.

RESULTS

Thirty-three patients were enrolled from September 2013 to August 2015. Their median age was 71 years, and 78.8% were men. Their median bodyweight and BMI were 72.3 kg (range, 53.8-82.5 kg) and 26.0 kg/m² (range, 23.5-31.0 kg/m² ), respectively. The patients achieved a mean weight loss of 4.5% (95% confidence interval [CI]: 3.8-5.1), corresponding to 3.2 kg (95%CI: 2.7-3.7 kg). Body fat mass was significantly decreased by a mean of 2.5 kg (95%CI: 1.9-3.1), whereas skeletal muscle mass was unaffected (mean: -0.20 kg [95%CI: -0.55-0.15]). The visceral fat mass reduction rate was high as 16.8% (range, 11.6%-22.0%). All patients underwent laparoscopic gastrectomy as planned. Severe postoperative morbidity (Clavien-Dindo grade ≥III) was seen in only one patient (3.0%).

CONCLUSION

The preoperative 20-day very low-calorie diet weight loss program is promising for the treatment of obesity before laparoscopic gastrectomy for gastric cancer.