Author's Accepted Manuscript

Laparoscopic Roux-en-Y Gastric Bypass inAdolescents with Morbid Obesity- SurgicalAspects and Clinical Outcome

G. Göthberg, E. Gronowitz, C.-E. Flodmark, J.Dahlgren, K. Ekbom, S. Mårild, C. Marcus, T.Olbers

PII: S1055-8586(13)00067-XDOI: http://dx.doi.org/10.1053/j.sempedsurg.2013.10.015Reference: YSPSU50460

To appear in: Seminars in Pediatric Surgery

Cite this article as: G. Göthberg, E. Gronowitz, C.-E. Flodmark, J. Dahlgren, K.Ekbom, S. Mårild, C. Marcus, T. Olbers, Laparoscopic Roux-en-Y Gastric Bypassin Adolescents with Morbid Obesity- Surgical Aspects and Clinical Outcome,Seminars in Pediatric Surgery, http://dx.doi.org/10.1053/j.sempedsurg.2013.10.015

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Laparoscopic Roux-en-Y Gastric Bypass in Adolescents with Morbid Obesity- Surgical Aspects and Clinical Outcome

G Göthberg1, E Gronowitz1, C-E Flodmark2, J Dahlgren1, K Ekbom3, S Mårild1, C Marcus3

and T Olbers1

1Sahlgrenska Academy at University of Gothenburg, Institute of Clinical Sciences, Dept. of Surgery, Medicine and Pediatrics and Centre of Obesity at the Queen Silvia Children’s Hospital, Gothenburg, Sweden 2 Childhood Obesity Unit, Skåne University Hospital, Malmö, Sweden

3Karolinska Institutet, Dept of Clinical Science, Intervention and Technology (CLINTEC) Division of Paediatrics, and National Childhood Obesity Centre, Children´s Hospital, Karolinska University Hospital, Stockholm, Sweden

Clinicaltrials.gov identifier: NCT00289705

Correspondence to: Dr Torsten Olbers, Dept for Gastrosurgical Research and Education,

Sahlgrenska University Hospital, 41345 Gothenburg, Sweden, torsten.olbers@gu.se

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Abstract

In this paper we address surgical aspects on bariatric surgery in adolescents from a nationwide

Swedish study

Eighty-one adolescents with morbid obesity (13–18 years) underwent laparoscopic gastric

bypass surgery while 81 adolescents with obesity matched by age, sex, and BMI received

conventional care. Another comparison group was adults undergoing gastric bypass at same

institution during the same time period. This report addresses the two-year clinical outcome

and five-year surgical adverse event rate.

Body-weight decreased form 133 kg (SD 22) at inclusion to 92 kg (SD 17) after one year and

89 (SD 18) after two years (p<0·001) representing a 32% (-35 to -30) weight loss after two

years, corresponding to 76% (-81 to -71) excess weight loss. Weight loss was similar in the

adult gastric bypass patients (-31%) while weight gain (+3%) was seen in the conventionally

treated obese adolescents. Significant improvement in cardiovascular and metabolic risk

factors and inflammation was seen after surgery. The treatment was generally well tolerated

and quality of life improved significantly. The surgical adverse events included

cholecystectomies (10%) and operations for internal hernia (9%) but no postoperative

mortality.

Adolescents undergoing laparoscopic gastric bypass surgery achieve similar weight loss to

adults. Improvements in risk factors and quality-of-life were substantial. There were surgical

complications similar to the adult group, which may be preventable.

Key words: Adolescent, bariatric, surgery, gastric bypass

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Introduction

An increased risk of cardiovascular and endocrine disorders, metabolic syndrome, various

cancers and psychological problems in adolescents with severe obesity1-3 collectively results

in an increased risk of reduced quality of life and shorter life expectancy4. Yet behavioral

intervention constitutes the cornerstone of childhood and adolescent obesity treatment,3 the

results for adolescents are modest5. Among obese adolescents, the effect seems to be absent

and undoubtedly insufficient for long-term risk reduction6.

The most successful long-term treatment strategy for severely obese adults is bariatric

surgery, where long-term weight loss is associated with a decrease in mortality and morbidity

and improvements in quality of life7-9.

Few reports on bariatric surgery in adolescents exist in the literature, and surgery is not

generally endorsed under the age of 18 years except in extreme cases10. O’Brien and

colleagues published the only randomized trial between lifestyle intervention and

laparoscopic gastric banding surgery for morbid obesity demonstrating favorable weight loss

and improvements in cardiovascular risk factors as well as improved quality of life in the

surgically treated group11.

This paper, based on A Swedish nationwide study (AMOS)12, addresses the safety and

efficacy of using laparoscopic Roux-en-Y gastric bypass (gastric bypass) surgery in severely

obese adolescents which were followed for up to five years postoperatively regarding adverse

events. We are also reporting previously published data regarding weight changes up to two

years, in comparison to a conventionally treated adolescents group and an adult group

undergoing the same surgery as well as changes in metabolic risk factors and quality of life.

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Material and Methods

Baseline characteristics and 1 and 2 year outcomes has previously been reported for three

groups of patients recruited between February 2006 and June 200912. The study is called

AMOS (Adolescent Morbid Obesity Surgery). In this paper we summarize results and expand

the presentation regarding surgical adverse events until Sept 2013.

Obese adolescents treated with gastric bypass

All adolescents referred to three specialist pediatric units in Sweden (Stockholm, Gothenburg

and Malmö) were offered assessment for gastric bypass surgery if they had been in a

comprehensive weight program and fulfilled the inclusion criteria of the study.

Inclusion criteria

- Consent to undergo surgical treatment

- Aged 13–18 years

- BMI≥40 or

- ≥35 kg/m2 with comorbidity (type 2 diabetes, sleep apnea, joint pain, high blood lipids).

- Pubertal Tanner stage >III and passed peak height growth velocity

Exclusion criteria

- Severe or insufficiently treated psychiatric disorder

- Ongoing drug abuse

- Obesity due to syndromes, monogenic disease or brain injury

- Reluctance to undergo long-term follow-up

Eighty-two adolescents were recruited. They had been in a comprehensive conventional

treatment program for at least one year and had passed the assessment for inclusion and

exclusion criteria after meeting a pediatrician, psychologist and dietician. Recruitment took

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place between Feb 2006 and April 2009. One of the patients refused surgery on the day of the

operation; thus, 81 individuals (35% boys) underwent surgery (Table 1).

Controls

Obese adolescent receiving conventional treatment= controls

During the recruitment period, 81 adolescents (43% boys) were selected from the Childhood

Obesity Register in Sweden (BORIS) as conventional treatment controls (Table 1.)

Obese adults treated with gastric bypass

Eighty-one obese adults undergoing gastric bypass were matched by gender with the obese

adolescents obtaining surgery, ensuring that date of surgery coincided within ±1 month (table

1). The inclusion age was 35–45 years at surgery; all other inclusion and exclusion criteria

were the same as for the adolescents (Table 1).

Anthropometry, height and weight

Height was measured to the closest centimeter using a wall-mounted standard stadiometer

with the patient in standing position. Weight was measured with the subject in light clothing

to the nearest 0·1 kilogram on an electronic scale, which was calibrated at regular intervals.

In the adult group, weight was measured at inclusion and one year postoperatively, while two-

year weights were normally from measurement at their general practitioner. (Table 1.)

Surgery

Surgical patients were instructed to remain on a low calorie diet (LCD) for the three weeks

leading to surgery. The laparoscopic Roux-en-Y gastric bypass consisted of a small (<20 ml)

gastric pouch and an ante-colic, ante-gastric Roux-en-Y construction with a 80 cm long Roux

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limb as described in detail elsewhere (Fig 1)13.

The technique is an original technique using a “double loop technique” which subsequently is

reconstructed to a true Roux-en-Y construction. The gastro-enteroanastomisis and entero-

entero anastomoses are created using a combined technique of linear stapling and hand

suturing.

Patient is placed in a supine position with the surgeon standing on the patient’s right side and

the assistant on the left. We recommend the use of four 12mm ports along with a Nathanson

liver retractor.

The Gothenburg technique to perform laparoscopic Roux-en-Y gastric bypass has been

established as the “gold standard” for bariatric surgery in the Scandinavian countries and

many surgeons all over the world. The technique was published as an original technique in

2003.13

We consider the main advantages to be:

a. The entire construction can be inspected during the whole procedure, thus limiting the risk

of technical errors

b. The gastro-enteroanastomosis in performed in a simplified way by using a combination of

linear stapling and hand suturing.

c. The technique is reasonably easily learnt, provided a good previous knowledge about

advanced laparoscopic techniques.

Initially was used a seven port technique but over the latest years we have reduced the number

of ports to four 12mm plus using the Nathanson liver retractor. The patient is placed in a

regular supine position with footrest and 30° anti Trendelenburg. Surgeon stands on the

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patient’s right side and the assistant on the left side.

Some technical issues:

1. The stomach pouch should be as small as technically feasible (<20 cc) aiming at leaving

only 1-2 cm of free stomach wall below the fatty pad of cardia on the anterior wall and avoid

including bulging back wall of the stomach.

2. A routine vertical split of the omentum enables a relatively easy pull up of the loop to the

pouch in almost all cases.

3. One should beware not to kinking the jejuno-jejunostomy if closure of the mesenteric

defect is used. This can lead to relative or total obstruction. However, mesenteric windows

were not routinely closed at the time of the study, but is today.

The technique includes no element in any way to limit the lumen of the GE thus leaving a

fully open passage for food to pass direct to the Roux limb. Our figures for postoperative

weight-loss match international standards (84% excess weight loss after 2 years), indicating

that a stoma size limitation is not an essential mechanism of action in the gastric bypass

construction.

One of two experienced gastric bypass surgeons performed all procedures, assisted by a

pediatric surgeon. All subjects, both adolescents and adults, were operated at Sahlgrenska

University Hospital, using the same surgical technique.

Follow-up after surgery

The adolescent surgical patients were assessed one month before surgery and 1, 3, 6, 12, and

24 months after surgery. Body weight and biochemical analyses were performed

preoperatively and at 12 and 24 months after surgery.

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All subjects in the adolescent surgical group were prescribed daily multivitamin and mineral

supplements, vitamin B12 and Calcium–Vitamin D combination tablets. The girls were

prescribed iron tablets in addition.

Health-related quality of life

SF-36 v2 was used to measure generic health-related quality of life.14 SF-36 comprises eight

general health domains and scale scores range from 0 to 100, with higher scores indicating

better health status. Summary scores for physical and mental health are calculated using

norm-based scoring with a mean of 50.

Adverse events

Surgical adverse events have prospectively been assessed up to five years postoperatively in

surgical subjects. Adverse events were prospectively recorded in an e-CRF. A complementary

retrospective survey of medical records was conducted to capture missing data.

Statistical analysis

Descriptive statistics are given as means with standard deviations or medians with range.

Changes over time are expressed with 95% confidence intervals.

All p-values are two-tailed and p<0.05 was considered statistically significant. Statistical

analyses were carried out using the Stata statistical package 10.1 (Stata-Corp. 2007. Stata

Statistical Software: Release 10.1. College Station, TX; StataCorp LP.).

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Results:

Baseline characteristics

Conventionally treated adolescents had a somewhat lower BMI than surgically treated

adolescents at baseline (BMI 42.0 vs. 45.5 respectively), and the corresponding values for

BMI standard deviation score were 3.9 vs. 4.1 (table 1). The proportion of males was 35% in

both surgical groups and 43% in conventionally treated adolescents. The mean body weight at

inclusion was 133 kg (SD 22 kg) in adolescents undergoing surgery, 124 kg (SD 21 kg) in

conventionally treated adolescents and 127 kg (SD 20 kg) in adults undergoing surgery. Mean

ages in the surgical groups were 16.5 years (SD 1.2) for adolescents undergoing surgery, 39.7

years (SD 2.9) for the adults and 15.8 years (SD 1.2) for the conventionally treated

adolescents.

In the adolescent surgical group twenty-five (31%) had neuropsychiatric diagnoses, 13 (16%)

had existing or previous self-destructive behavior and 33 (41%) had contacts with pediatric

psychiatric units. Poor school performance (truancy, leaving school without a diploma) was

frequently reported (>50%). Twenty-six adolescents (32%) had no recorded psychosocial

problems.

Primary hospitalization and postoperative complications

Median surgical time was 63 min (range 38–106) in the adolescent group. Median

postoperative inpatient stay was 4 days (range 2–11). None of the patients required treatment

in the intensive care unit. Two patients required blood transfusions for postoperative bleeding

and another was re-hospitalized with fever three days after being discharged and received

intravenous antibiotics due to an intra-abdominal infection confirmed by CT scan.

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Weight changes

There was a 100% follow-up rate at one and two years for weight and height in both groups

undergoing surgery. In the conventionally treated adolescent group there was a 100% follow-

up for weight after one year, but this dropped to 73% (59 individuals) after two years.

As demonstrated in figure 2, there was a similar reduction in weight in the adolescent and

adult groups undergoing surgery, while conventionally treated adolescents had increased their

weight slightly. Weight change after two years was -32% (CI -35% to -30%) in surgically

treated adolescents, as compared to weight gain of +3% (CI 0–7%) in the conventionally

treated adolescents, and weight loss of -31% (CI -34% to -29%) in adults undergoing surgery.

Ninety-five per cent of operated adolescents achieved a weight loss exceeding 50% of excess

weight.

There were no significant differences in the weight loss between genders. Fifty-seven per cent

of the adolescents in the surgical group had a continuing weight loss while 43% increase in

weight during the second year after surgery (range -9.7 to +4.2 kg).

Changes in quality of life

In summary, one-year follow-up, significant improvements were observed in seven of the

eight SF-36 health domains and in the physical component summary score12. After two years,

significant improvements compared to baseline were evident in all four physical health

domains, in the physical component summary score, and in two of the four mental health

domains. Minor decreases in SF-36 scale scores between one- and two-year follow-up did not

reach significance.

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Adverse events in surgically treated adolescents

During the two-year follow-up, twelve adolescents (15%) underwent additional surgical

interventions, five (6.2%) needed an operation for internal hernia; six (7.4%) underwent

cholecystectomy due to symptomatic gallstone and one was laparoscopically operated with

finding of adhesions. Four patients visited an emergency intake due to non-specific abdominal

pain. Additional incomplete follow up until five years postoperatively revealed four others

operated for ileus, two for internal hernias and two more were cholecystectomized. All

remedial surgeries were performed by laparoscopy.

We identified poor compliance in the intake of prescribed vitamin and mineral supplements in

two thirds of patients.

Excess skin

Most adolescents having undergone surgery experienced problems with excessive skin

following weight loss; this aspect was not formally addressed in the current study.

Discussion

In this study we could demonstrate a substantial weight loss over two years (32%) following

gastric bypass surgery for severely obese adolescents, which was similar to the weight loss in

an adult comparison group (31%). Ninety-five per cent of operated adolescents achieved more

than 50% excess weight loss. Minor weight gain (3%) was seen in conventionally treated

adolescents. Cardiovascular risk factors were ameliorated, mirrored by lowering of insulin

and serum lipids levels, and a reduction of inflammatory activity12. Furthermore, we have

shown improvement in quality of life after surgery, although psychological and surgical

adverse events occurred.

RYGB has established as the “gold standard” in Scandinavian bariatric surgery and

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constitutes currently more than 90% of bariatric procedures. One previous study has

demonstrated that laparoscopic gastric banding is feasible and effective in adolescents

recruited directly from the community when compared to the best conventional therapy11. In

contrast, other studies have not been successful with gastric banding in adolescents15. A

previous gastric banding study for adolescents in Sweden was abandoned due to poor results

and, together with the fact that gastric bypass has compared favorably with gastric banding in

most studies, we considered gastric bypass to offer the best trade-off between weight loss and

initial risks with surgery.

We currently recommend closure of mesenteric defects as also proposed by others16. At the

time of surgery in this study we hadn’t established a safe technique for closure of defects and

therefore didn’t want to insert an element of learning curve in this series. A medical

prophylaxis for gallstone formation was not used in this series but obviously even adolescent

develop gallstones as a result of rapid weight and a prophylaxis with ursodeoxycholic acid

should be considered17.

We offered surgery to a consecutive group of adolescents demonstrating a high prevalence of

psychiatric and psychosocial morbidity and refractory to conventional treatment in tertiary

medical centers involved in this study. Despite having a fourth of outpatient visits compared

to the study by O’Brien et al11, the weight loss among adolescents in this study was similar to

an adult comparison group undergoing gastric bypass surgery. This indicates that

physiological mechanisms are strong determinants of weight loss after gastric bypass surgery

rather than learned lifestyle changes. Until recently, the success of gastric bypass was

attributed to mechanical restriction through gastric volume reduction and calorie

malabsorption as a consequence of the bypass of the duodenum and proximal jejunum. Other

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mechanisms contributing to weight loss after gastric bypass include: reduced hunger18,

augmented satiety19-21, increased energy expenditure22 , and altered taste perception, all of

which may be at least partly mediated by alterations in gastrointestinal and central neuro-

endocrine signaling.

We observed a substantial amelioration in cardiovascular risk factors with significantly better

glucose and lipid control, as previously demonstrated in adults12. A theoretical advantage of

early intervention would be a shorter exposure to metabolic risk factors and thereby reduced

risk for developing structural and functional cardiovascular impairment. Furthermore, fasting

insulin levels decreased to one fourth of preoperative levels. We also found a major decrease

in inflammatory activity postoperatively, as previously demonstrated in adults after bariatric

surgery23 .

A possible disadvantage of intervention in adolescents could be their physical and

psychological immaturity. Therefore, the poor compliance in vitamin and mineral

supplementation requires careful attention for a long time. Another issue that needs

consideration in adolescents is the development of excessive skin as a result of weight loss,

which we will address in a separate paper from this study.

There were broad improvements in quality of life in adolescents after surgery from a group

perspective, supporting the findings of a previous study24. We consciously did not exclude

patients with psychiatric and psychosocial problems in this study possibly leading to more

psychosocial issues in the cohort. When treating this group of patients the multidisciplinary

team must offer an extended postoperative support role, as recommended previously25.

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In summary, we have demonstrated that RYGB surgery results in similar weight loss in

adolescents as in adults over two years. We found substantial improvements in risk factors for

co-morbidities and improvements in quality of life. Nonetheless, the surgical and psychiatric

adverse events that appeared in this psychosocially vulnerable cohort require careful attention.

It appears so far that RYGB is a viable option for future interventional studies in severely

obese adolescents.

Acknowledgements:

Primary funding source: Research council, Västra Götalandsregionen, Sweden,

http://www.vgregion.se/sv/Vastra-Gotalandsregionen/startsida/

Additional funding source:

Fru Mary von Sydow’s foundation, Gothenburg, Sweden

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Legends to figures Figure 1: Surgical construction of Roux-en-Y gastric bypass13

Figure 2 Weight change over two years in adolescents and adults undergoing gastric bypass surgery (n=81+81) and adolescents in conventional treatment (n=81). Mean (95% CI). Table 1: Baseline anthropometric characteristics Table 2. Surgical adverse events up to 5years postoperatively in 81 adolescents who have undergone Laparoscopic gastric bypass

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Figure 1: Surgical construction of Roux-en-Y gastric bypass13

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Figure 2 Weight change over two years in adolescents and adults undergoing gastric bypass surgery (n=81+81) and adolescents in conventional treatment (n=81). Mean (95% CI).

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Table 1: Baseline anthropometric characteristics BMI values were related to Swedish standards for age and gender with standard deviation score (BMI SDS). Mean (SD).

Adolescents -surgery

Adolescents-control with obesity

Adults- surgery

number total 81 81 81

male/ female 28/53 35/46 28/53 Age (yrs)

total 16.5 (1.2) 15.8 (1.2) 39.7 (2.9) male 16.6 (1.3) 15.9 (1.2) 40.2 (3.5)

female 16.5 (1.1) 15.7 (1.3) 39.5 (2.6) Height (m)

total 1.71 (9.3) 1.71 (9.3) 1.71 (0.1) male 1.78 (10.4) 1.78 (7.9) 1.82 (0.1)

female 1.67 (6.4) 1.66 (7.7) 1.66 (0.1) Weight (kg)

total 133 (22) 124 (21) 127 (20) male 147 (23) 135 (20) 142 (17)

female 125 (17) 115 (17) 120 (17) BMI (kg/m2)

Total 45.5 (6) 42.0 (5) 43.5 (5) male 47.0 (6) 43.0 (5) 43.0 (6)

female 45.0 (6) 42.0 (5) 44.0 (5) BMI (SDS)

total 4.1 (0.45) 3.9 (0.39) nd male 4.4 (0.45) 4.0 (0.39) nd

female 4.1 (0.43) 3.9 (0.39) nd

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Table 2. Surgical adverse events up to 5years postoperatively in 81 adolescents who have undergone

Laparoscopic gastric bypass

Age at event Time after op

Primary hospitalization Surgical/physical adverse event

Girl 14 and 15 y 1st day and 15 months

postoperative haemorrhage, low haemoglobin , transfusion

Laparoscopic cholecystectomy

Girl 16 y 1st day postoperative haemorrhage, low haemoglobin , transfusion

Girl 15 y 2 weeks and 2,5 yrs. post op

Fever and elevated CRP, hospital stay for 5 days, antibiotics

Ileus op by laparoscopy

Boy 17 y 2 months Internal hernia, op by laparoscopy Girl 16 y 3 months Internal hernia op by laparoscopy Girl 16 y 5 months Recurrent abdominal pain, laparoscopic adhesiolysis Girl 15 yrs. 9 months Laparoscopic cholecystectomy Girl 18 y 9 months Abdominal pain Boy 16 y 10 months Internal hernia, op by laparoscopy Girl 15 y 10 months Laparoscopic cholecystectomy Girl 18 y 12 months Laparoscopic cholecystectomy Girl 18 y 15 months Internal hernia op by laparoscopy Girl 17 y 15 months Internal hernia, op by laparoscopy Girl 18 y 18 months Abdominal pain Boy 17 y 19 months Abdominal pain Girl 18 y 20 months Laparoscopic cholecystectomy, Girl 16 y 20 months Laparoscopic cholecystectomy Girl 14 y 21 months Abdominal pain Girl 17 and 21 yrs. 1 and 5 yrs. Ileus and cholecystectomy Girl, 20 yrs. 2 yrs. Ileus op by laparoscopy Boy 19 resp 22 y 2 and 4,5 yrs. Cholecystectomy and internal hernia op by laparoscopy Boy 21 y 3 yrs. Internal hernia, op by laparoscopy Boy 19 yrs. 4 yrs. Ileus op by laparoscopy

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