BARIATRIC SURGERY
Mixed Techniques (In Part Restrictive And Primarily Malabsortive)
Mixed techniques are like the Scopinaro technique or the biliopancreatic diversion (figure below) and the variant Larrad technique or the Salmon technique (proximal gastric diversion and ringed vertical gastroplasty). They are more aggressive and combine the latter techniques, inducing deficient digestion and a decreased intestinal absorption (preferentially fats).
The incidence of complications ranges between 10-15%, with a rate of mortality between 1-3%. Post-operative nutritional complications include anaemia because of a deficit in iron of 30%, deficiencies of liposoluble vitamins of 30-50% and 3-5% chance of hospitalisation for reasons of protein malnutrition. These complications are reversible with supplements and proper dietary modifications and it is essential that there be closely monitored post-operative follow-up. The appearance of diarrhoea and foul smelling faeces is frequent and can limit social life.
With mixed techniques the medium of loss in excess weight is greater than 70% in the long term.
Currently, a rising percentage of bariatric surgical operations are being done through laparoscopy, obtaining similar weight-loss results to the open techniques, but with the advantages: less risk of abdominal hernias and eventration, infections of the surgical incision, and a more rapid post-operative recuperation with less pain, less lung complications, less time of hospitalisation and a return to active life in a shorter time. However, laparoscopy requires experience, is technically difficult and, in 20% of cases, the patient requires a shift to open surgery.
The evaluation of the obtained results regarding weight-loss should include criteria of efficacy (weight-loss, evolution of the ponderal index, resolution or the improvement of comorbidity associated with obesity), with at least 5 years of follow-up with the patient to measure quality of life and the satisfaction of the patient. Currently the evaluation of the results has been standardized using the BAROS (Bariatric Analysis and Reporting and Outcome System) system.
The parameters used included weight-loss in kilos (not considered a good measurement), percentage of initial weight lost, percentage of excess weight lost (percentage of excess weight in relation to the ideal weight, before and after the surgery) and the descent of the BMI. A successful bariatric surgery is considered to be when there is at least a 50% loss in excess weight, however this is difficult to attain in overweight patients (BMI>50Kg/m2). The best parameter to evaluate weight-loss is a descent in the BMI. It is accepted that a final BMI equal or greater than 35Kg/m2 is an insufficient result.
Bariatric surgery is also considered justified for its impact on the improvement or resolution of comorbidity: resolution of type 2 Diabetes Mellitus, improvement of arterial hypertension, cholesterol and triglycerides, cardiovascular function, sleep apnea syndrome, asthma, arthropathy and infertility, among others.