Pre-operative Very Low Calorie Ketogenic Diet (VLCKD) vs. Very Low Calorie Diet (VLCD): Surgical Impact
Pre-operative diet may play an important role as far as patients’ fitness for surgery, post-operative outcomes, and successful weight loss. Our aim was to compare surgical outcome and weight loss in two groups of patients who were offered two different pre-operative kinds of diet: very low calorie diet (VLCD) and very low calorie ketogenic diet (VLCKD).
Patients candidate for bariatric surgery (laparoscopic sleeve gastrectomy) were registered and assessed according to pre- and post-diet BMI, operative time, hospital stay, drainage output, and hemoglobin (Hb) levels. Patients’ preference influenced the type of diet.
From January to December 2016, 178 patients (139 F and 39 M) were enrolled in this study. The mean age was 43 years. In total, 72 patients were on VLCKD while 106 patients on VLCD. Pre-diet mean BMI was 46.3 ± 6.3 kg/m2 for VLCKD group and 43.1 ± 6.9 kg/m2 for VLCD group, while immediately pre-op BMI were 43.9 ± 5.9 kg/m2 and 41.9 ± 6.8 kg/m2, respectively. Drainage output and hemoglobin levels after surgery resulted significantly correlated with diet induced BMI reduction (141.2 ± 75.8 vs. 190.7 ± 183.6 ml, p = 0.032; 13.1 ± 1.2 vs. 12.7 ± 1.5 g/l, p = 0.04). The percentage of patients requiring a hospital stay longer than anticipated (> 3 days) was 2.8% in the VLCKD group and 10.4% in the VLCD group (p = 0.048).
In our experience, VLCKD showed better results than VLCD on surgical outcome, influencing drainage output, post-operative hemoglobin levels, and hospital stay.
KeywordsBariatric surgery Pre-operative diet Laparoscopic sleeve gastrectomy
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Informed consent was obtained from all individual participants included in the study.
Statement of Human and Animal Rights
For this type of study, formal consent is not required.
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