[Preoperative weight loss in bariatric surgery candidate patients. evidence-based recommendations]

Bariatric surgery is becoming increasingly more common in the treatment of morbid obesity in our hospitals. One of the measures being used to optimise the results of this surgery seems to be the standardising the preoperative weight loss. As there are no universal recommendations for carrying out this weight loss, a review of this topic is presented.

To analyse whether sufficient scientific evidence exists to recommend preoperative weight loss in candidate patients for bariatric surgery. What would be the best options to carry out this weight loss is also analysed, as well as making some recommendations based on the scientific evidence.

There is great heterogeneity in the designs of the different studies, with different guidelines for weight loss and various surgical techniques. However, preoperative weight loss leads to a decrease in the size of the liver and intra-abdominal fat, which improves the surgical field and intra-operative view, which in turn helps during the surgical act, both in open as well as laparoscopic surgery. There is no consensus on the effect of preoperative weight loss has in predicting the medium or long term results after bariatric surgery.

The current scientific evidence makes preoperative weight loss recommendable in candidate patients for bariatric surgery. However, there is no consensus on what is the best procedure to achieve this preoperative weight loss.