Weight loss prior to bariatric surgery: An updated review of the literature

Abstract

Background and Aims: prior to bariatric surgery, a preoperative weight-reducing regimen is usually adhered to in most centers. the clinical effects of such a regimen are yet to be determined.Material and Methods: We reviewed the current literature by searching in pubMed for publications reporting clinical effects resulting from a preoperative weight loss regimen prior to bariatric surgery published from January 1, 1995 to april 30, 2014.Results: in total, we identified 23 original publications and 2 review articles which met all inclusion criteria. these were included and fully analyzed with regard to effects of preoperative weight loss. in general, for parameters such as operating time and intraoperative complications including blood loss and recovery, inconsistent data were reported. Most studies included low number of patients and with heterogenic designs, and the results could not form the base for recommendations. however, for outcomes such as postoperative complications and weight development over time, data from large-scale studies and randomized controlled trials suggest beneficial effects following adherence to weight loss prior to bariatric surgery.Conclusion: although a large amount of data in the current literature on the effects of weight loss prior to bariatric surgery are inconsistent for many outcome parameters, recently published results regarding effects on postoperative complications and weight development over time strongly suggest that such a regimen should be recommended. Whether a certain degree of weight loss should be mandatory before being accepted for bariatric surgery is, however, still controversial.

Usefulness of an intra-gastric balloon before bariatric surgery

“…It is not clear in the published literature that the weight loss prior to bariatric surgery has any impact on surgical morbidity (10,13,16,18). In fact, the influence of pre-surgical weight on surgical morbidity is also uncertain.…”

“…However, other retrospective studies have found that a pre-surgical weight loss of 5-10% EWL will have an impact on post-surgical morbidity (9,10,16,20), on the time duration of the surgery (19), on the amount of transfusions, and on the rate of conversions to open surgery (6,21,22). Other authors have found that pre-surgical weight loss is a predictive factor for a higher loss weight during post-surgical evolution (6,17), and would help to select those obese population who would benefit most from bariatric surgery.…”

“…However, some controversy exists as to whether pre-operative weight loss for bariatric surgery could have an impact on surgical morbidity, or on the long-term evolution of the patient (10,13,16).…”

(Preprint)

“…This is usually achieved with Low Calorie Diets (LCD) or Very Low Calorie Diets (VLCD), where the patient wholly or partly subsists on meal replacements such as shakes, soups and puddings which provide 600-800 kcal/day [12]. A systematic review and meta-analysis has shown that preoperative weight loss results in shorter operating times and improved weight loss a year after surgery [13].…”

Dieta de muito baixo valor calórico em obesos mórbidos no período pré-operatório de cirurgia bariátrica: análise da alteração da composição corporal durante perda de peso aguda

“…Alguns estudos demostraram que a perda de peso em indivíduos com obesidade mórbida antes da cirurgia bariátrica promoveu controle das comorbidades, redução do risco cirúrgico, de infecções e de mortalidade, e aumento a adesão do paciente no período pós-operatório 15,16,17,18 .…”