Safety and Effectiveness of Single-Anastomosis Duodenal Switch
Procedure: 2-Year Result from a Single US Institution
Rena C. Moon
Andre F. Teixeira
Muhammad A. Jawad
Published online: 22 December 2017
Springer Science+Business Media, LLC, part of Springer Nature 2017
Background Single-anastomosis duodenal switch (DS) was introduced by Sanchez-Pernaute et al. as a modification of the
biliopancreatic diversion with duodenal switch. We have published preliminary results of the loop DS as the first report of the
procedure in the USA. This study aims to evaluate the loop DS procedures again, in terms of weight loss, comorbidity resolution,
complication rate, and address the nutritional concerns.
Methods A retrospective chart review was performed on initial 128 patients who underwent laparoscopic or robot-assisted
laparoscopic single-stage loop DS between December 17, 2013 and September 23, 2016. Sixteen additional patients were
prospectively enrolled from September 24, 2016 to May 4, 2017.
Results A total of 102 female and 38 male patients were included in this study with a mean age of 41.2 ± 9.6 years. The mean
body mass index (BMI) at the time of procedure was 57.3 ± 9.2 kg/m
. Percentage of total weight loss was 23.1, 37.1, 42.9, and
44.7% at 6, 12, 18, and 24 months, respectively. Percentage of excess BMI loss was 41.9, 68.1, 76.6, and 80.8% at 6, 12, 18, and
24 months, respectively. Mean levels of HbA1c, triglyceride, and LDL-cholesterol decreased significantly after the loop DS.
Regarding the fat-soluble vitamins, majority of patients had vitamin A and E levels in the normal range. However, 42 to 56% of
the patients had low levels of vitamin D at 6, 12, and 24 months following the procedure. Mean length of hospital stay was 4.1 ±
2.7 days. Thirty-day readmission rate was 7.6% (n = 11), and 30-day reoperation rate was 6.9% (n =10).
Conclusions Loop DS seems to be effective in weight loss and is a feasible operation in the super-obese population. However,
close monitoring of liver enzymes is warranted in addition to nutritional follow-up.
Keywords Single anastomosis
Single-anastomosis duodeno-ileal bypass with sleeve gastrec-
tomy was first introduced in 2007 by Sanchez-Pernaute et al.
 from Spain. Since then, the group has modified the length
of the efferent loop from 200 to 250 cm in order to decrease
the complications that were caused by excessive malabsorp-
tion . The same group has published several reports that
showed a great weight loss, along with high rate of comorbid-
ity resolution, at a minimal rate of complication [2–4].
However, the American Society for Metabolic and Bariatric
Surgery (ASMBS) issued a statement regarding single-
anastomosis duodenal switch (DS) and defined it as an exper-
imental procedure due to lack of Brandomized or prospective
comparative data^ and Blimited data regarding long-term nu-
tritional effects^ . Since then, only two other groups in the
USA have published outcomes of the loop DS. One group
showed superior weight loss of the loop DS at 18 months after
tomy (LSG), and similar weight loss as reported by Sanchez-
Pernaute et al. . We have been performing loop DS since
2013, and are the other group who have published preliminary
results of the loop DS in our initial 72 patients as the first
report of the procedure in the USA . This study now in-
cludes 144 patients in total, with a longer follow-up and
follow-up on laboratory data, and aims to evaluate the loop
DS procedures again, in terms of weight loss, comorbidity
* Muhammad A. Jawad
Department of Bariatric Surgery, Orlando Regional Medical Center,
Orlando Health, 89 W Copeland Dr, 1st Floor, Orlando, FL, USA
Obesity Surgery (2018) 28:1571–1577