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ABCD. Arquivos Brasileiros de Cirurgia Digestiva (São Paulo)

Print version ISSN 0102-6720

ABCD, arq. bras. cir. dig. vol.25 no.4 São Paulo Oct./Dec. 2012 



Ring influence on ponderal evolution after four years of laparoscopic Roux-en-Y gastric bypass



Irineu Rasera-JuniorI, III; Natalia Moreno GainoI; Maria Rita Marques de OliveiraII; Patrícia Fátima Sousa NovaisI, IV; Celso Vieira de Souza LeiteIII; Maria Aparecida Coelho de Arruda HenriIII

IBariatric Clinic, Hospital Fornecedores de Cana, Piracicaba, SP
IIBiociences Institute of Paulista State University (UNESP), Botucatu, SP
IIIFaculty of Medicine of Paulista State University (UNESP), Botucatu, SP
IVFaculty of Pharmaceutical Sciences of Paulista State University (UNESP), Araraquara, SP, Brazil





BACKGROUND: Use of ring in Roux-en-Y gastric bypass is still a matter of controversy among bariatric surgeons. There is no consensus on its impact in relation to weight loss and weight maintenance in the long term.
AIM: To evaluate the influence of the ring on the evolution of body weight over four years after bariatric surgery.
METHODS: Retrospective analyzis of 143 women who underwent laparoscopic Roux-en-Y gastric bypass paired on the use or not use of Silastic® ring. Follow-up time was 48 months. Inclusion criteria were age over 18 years, primary bariatric operation and regular attendance at the clinic during the period of interest for research. The technique kept small gastric reservoir estimated in a volume of 30 ml. The food limb had in average 150 cm and the bile one 40 cm from the duodenojejunal angle. The group "ring" used Silastic® device with length of 6.5 cm, placed 2 cm from gastrojejunal anastomosis. The ring was closed for five polypropylene surgical thread sutures. In the morning after surgery the patients received isotonic fluids; on the second day salty liquid diet and were discharged on the third day. Semisolid diet started from the 20th day and solid on the 30th, with daily tablet of polivitamins.
RESULTS: The weight loss was larger on the ring than without ring groups in all periods, respectively 10% and only 5% in the third postoperative year. The proportion of not having reached the 50% excess weight loss expectative was significantly higher in the group without ring than in the group with the ring (31% and 8% respectively in the fourth year). There was no difference between groups in delayed recovery of weight lost with the operation.
CONCLUSIONS: The results were favorable to use the ring exclusively when it is analyzed only the weight loss.

Headings: Gastric bypass. Gastroplasty. Bariatric surgery. Weight loss.




The ring use in Roux-en-Y gastric bypass (DGYR) is still a matter of controversy among bariatric surgeons. Considered the "gold standard" of operations to control body weight5 in morbidly obese, DGYR includes the optional use of a prosthesis in the terminal portion of the gastric remnant - the containment ring or gastric banding. However, there is still no consensus about the impact caused by this increase in gastric restriction in relation to weight loss and weight maintenance in the long term.

The use of constricting the gastric pouch began with Linner & Drew in 19859,17, who employed an element of restraint to prevent possible expansion of gastroenterostomy. Subsequently, Fobi11 and Capella6 proposed changes in DGYR including synthetic materials in the distal end of the gastric pouch to restrict emptying.

Placing the ring upstream of the gastrojejunal anastomosis is considered effective and sustainable alternative to enhance weight loss in morbidly obese patients, although intermediate and late results are still relatively scarce in the literature21,22.

After bariatric operations weight reduction is clearly visible, with consequent improvement of comorbidities and quality of life. However, the individual may recover partially or even totally the lost of weight if changes his lifestyle and dietary practices regarding physical activity do not occur12. Some studies have indicated an uncomfortable weight gain in the late postoperative period7,18, especially between the 3rd and 5th postoperative year. Failure to use the containment ring may be related to a larger later increase in weight compared to patients who do not have this prosthesis13. Weight gain after surgery should be targeted for study and monitoring, with the aim of preserving the benefits obtained.

Whereas there are few studies evaluating the limiting factor of the ring or if it significantly interferes with the maintenance of weigh loss, this study is justified. The objective was to evaluate the influence of the ring on the evolution of body weight over four years after bariatric surgery.



The study involved 143 women attended in Bariatric Clinic® - Hospital Fornecedores de Cana, Piracicaba, SP, Brazil, accredited by Surgical Review Corporation TM. These women were classified as to have the presence (ring: n = 75) or absence (no ring: n = 68) of the restriction ring, with the follow-up time of 12, 24, 36 and 48 months. It is one retrospective study of the medical records from 1999 to 2005. For inclusion in the study were used the following criteria: age over 18 years, primary bariatric surgery and regular attendance at the clinic during the period of interest for research, women who agreed to participate in the study after signing the informed consent. The study was approved by the Research Ethics Committee of the Paulista State University, School of Pharmaceutical Sciences of Araraquara under number 16/2006. In Table 1 it can be seen that the weight and age of the study participants were similar in both groups.

The technique used was laparoscopic DGYR, gastric reservoir with small curvature and estimated volume of 30 ml and manual gastrojejunal anastomosis in two planes with dimensions between 1.5 and 2.0 cm. The food limb had150 cm and bile limb 40 cm from the Treitz angle. The average time of surgery was 130 minutes, ranging from 250 to 90 minutes of the first in relation to the latest. The drainage of cavity was done with tubulolaminar vacuum drain routinely. The group "ring" used annulus of Silastic ®, length of 6.5 cm, placed at a distance of two inches from gastrojejunal anastomosis. The ring was closed by polypropylene five sutures. The morning after surgery the patients received water, coconut water and isotonic solutions and, on the second day, liquid diet without salt; discharge was on the third postoperative day. Soft diet was started from the 20th day after surgery and solid on the 30th day, along with daily single tablet of multivitamin.

Data were obtained from electronic medical records in the computerized system of the surgery center, collecting data related to body weight preoperatively and at 12 months after surgery.

With women grouped according to the type of surgery and the time of follow-up, were analyzed loss of excess weight and the recovery of excess weight relative to the lowest weight attained after surgery. The amount of weight excess was obtained from the weight difference between the preoperative and the ideal weight, according to international standards(1 9). Women who remained in the study until 48 months were evaluated in paired manner.

Data analysis

Data were tabulated, with absolute weight and transformed into relative values expressed as median percentages. Comparisons between the medians were performed using the Mann-Whitney, after finding the characteristics nonparametric data. Comparisons between more than two groups of data were made by Friedman test. The proportions between dichotomous categorical variables were tested by Fisher's exact test. The level of significance was set at 5%. Analyses were performed using the computer program BioEstat 3 ®.



The slimming on "ring" group could be considered higher than in the group "no ring" for all periods (12 m = 74% x 72%; 24 m = 79% x 76%; 36 m = 76% x 72% and 48 m = 76% x 71%) if adopted significance level of 10%; was significant in the third postoperative year at 5% (Table 2).

When assessing the number of patients whose loss of overweight was less than 50%, it was found that the proportion of not reaching this weight loss per period was significantly higher in the group "no ring" than in the group "ring" to 48 months (12 m = 25,9% x 2,7%; 24 m= 23,4% x 2,7%; 36 m= 28,8% x 5,3% and 48 m = 30,9% x 8,2%) (Table 3).



Figure 1 shows the paired analysis of women's groups "ring" and "no ring" followed by four years. It was found that both groups showed excess weight loss > 50% maintained until the fourth year after surgery. The curve of loss of excess weight in both surgical procedures shown marked on the first postoperative year, with stabilization after the second year. The curves remain constant distance between them. Even excluding the women followed for less than 48 months, the differences in the percentage of excess weight loss between the groups "ring" and "no ring" in the second and third year postoperatively were maintained.



The delayed weight recovery began after 24 months postoperatively in both groups and progressively increased (Table 4). There was no difference between groups "ring" and "no ring" in the amount of excess weight that was recovered at the different times. The median recovery were 6.5% and 8.4% overweight, respectively to the groups "ring" and "no ring" after four years from surgery. There was no difference between groups in the proportion of women who recover weight over time.

After the 4th year of DGYR in both groups, over 30% of patients had weight regain above 10% of weight excess. Around 10% of them, the recovery was greater than 20% of weight excess presented before surgery and lost up to 24 months (Table 5).




The results of this retrospective study suggest that the placement of the containment ring in gastric DGYR shows superiority in weight loss, but did not differ from the technique without ring in the stability of the weight lost during the time. The curves of changes in the percentage loss of excess weight (Figure 1) are clear by showing the upper positioning of ring group, although not statistically significant at the 5% level at all times. This is not a definitive conclusion about the advantages of using the ring, but provides evidence that, solely for the purpose of "weight loss" the higher restriction may be the most effective way.

Bessler3 in a randomized double-blind study with 90 superobese undergoing DGYR, with or without polypropylene band of 5.5 cm, obtained results of excess weight loss similar to this study in 12, 24 and 36 months with and without ring (12 m = 64% x 57,7%; 24 m = 64,2 x 57,7% e 36 m = 73,3 x 57,7). Likewise, the percentage of excess weight loss was always higher in the group with the ring, although significant at the 5% level after only in three years. Awad et al.2, after studying 244 patients undergoing DGYR, found loss of the excess weight of 81% and 80.5% after 24 and 36 months respectively, both statistically significant compared with the group without ring with loss of 69.6% and 63.9%. Arceo-Olaiz et al.1 in a controlled study with 60 patients, found no differences by 24 months.

Some limitations of this study, such as the fact that it is retrospective, nonrandomized, and with a convenience sample of moderate size, limits its conclusions. It must be also considered that losing weight is not the only criterion for measuring success or outcome in bariatric surgery. The authors chose not to include in this study the impact of comorbidities on the evolution, nor on the quality of life or intolerance in each food group, nor about the complications related to the use of the ring. These aspects will be the objective of future randomized trial. The focus of this paper was to verify the isolated action on body mass, which still sets itself up as a point of doubt in the current literature and may be a guide for the sample size calculation in prospective studies.

Very striking are the findings of the failures on group without ring, by considering as criteria of success a percentage loss of excess weight greater than 50%, acceptable among many investigators4,15. Nearly a third of the group without ring can be classified as failure according to this criterion. In the ring group only 8.2% did not reach the minimum for success after four years.

In relation to weight regain, there was no difference between the groups with and without ring. This recovery begins in the second year of surgery and progresses in terms of recovered weight ratio (Table 4) and prevalence (Table 5).

Among the techniques of DGYR variations exist, including the length and format of the new gastric pouch, and various sizes of gastrojejunal anastomoses with or without ring or not adjustable containment band. All these variations may influence the final results, which leads us to the hypothesis that the restrictive component is significantly influential. Virtually all patients have weight regain after lowering the restriction caused by the removal of the ring due to complications10. Gastric bypasses whose reservoirs are large, with little restriction, weight loss can lead to a modest capacity and high intake of solid food20, although it occurs decreased expression of ghrelin in the stomach. Likewise, gastrojejunal anastomoses too large may not generate satiety, although theoretically promote a greater release of glucagon-like peptide-1 (GLP-1) by the arrival of fast food into the small intestine.

The proof of the almost immediate and significant reduction of serum ghrelin after DGYR14 stimulated further questioning about the real need to use containment rings, since the mere fact of excluding most of the gastric fundus was enough to reduce hunger and provide weight loss. The DGYR promotes hormonal condition most favorable providing an environment for the intrinsic loss and maintenance of weight. But this mechanism appears to be outweighed by the power of mechanical restriction. If the restriction is small, can increase the chance of surgical failure, even in the presence of hormonal changes. If the restriction is excessive, it can cause complications. The DGYR even without ring presents significant degree of restriction of food intake. This retrospective study suggests that a bit more restricted, if it is medically acceptable without causing complications in high rates, may be beneficial to achieve greater than 50% loss of excess weight.

Several studies have shown that the use of ring in DGYR presents complications such as stenoses, erosions and intolerances within limits considered acceptable. Although the size of the ring is not consensus, the length between 6.0 to 7.0 cm is associated with a lower incidence of these complications while maintaining its restrictor function8. The evolution up to this measure followed shorter lengths attempts since 5.0 cm with prohibitive incidence of vomiting. Capella and others used polypropylene or Marlex ® not adjustable band instead of Silastic ® ring, with reports of good results3,6.

The weight recovery can occur for physiological adaptation processes that happen in the gastrointestinal tract over time. Adoption of healthy lifestyle instead old habits that contributed to the condition of obesity must be considered by patients. This new behavior is crucial for long-term maintenance of weight, since obesity is a chronic, progressive disease that has no cure and requires specialized treatment even after surgery.

The doctor-patient relationship is an important element when discussing the use of the ring. Nowadays, the authors consider reasonable to suggest that the team's experience and cultural factors are considered when deciding on the placement of the prosthesis or not, until more scientific evidence exist to define this issue.



Patients undergoing DGYR with the containment ring had gastric weight loss greater, statistically significant only at 36 months after surgery, and a higher proportion of surgical success (excess weight loss> 50%) in this period. The weight regain was not different between groups. Given the limitations of the study, the findings should be interpreted as calling for the use of the ring when considering only weight loss, but also as initial evidence for randomized trials with larger numbers of patients and variables, including assessments to quality of life.



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Irineu Rasera Júnior

Received for publication: 02/04/2012
Accepted for publication: 03/08/2012
Financial source: none
Conflicts of interest: none



From 1Bariatric Clinic, Hospital Fornecedores de Cana, Piracicaba, SP; 2Biociences Institute of Paulista State University (UNESP), Botucatu, SP; 3Faculty of Medicine of Paulista State University (UNESP), Botucatu, SP; 4Faculty of Pharmaceutical Sciences of Paulista State University (UNESP), Araraquara, SP, Brazil.

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