Long-term outcome after endoscopic stent therapyfor complications after bariatric surgery

Atif Iqbal • Brent Miedema • Archana Ramaswamy •

Nicole Fearing • Roger de la Torre •

Youngju Pak • Caleb Stephen • Klaus Thaler

Received: 6 May 2009 / Accepted: 13 April 2010 / Published online: 13 July 2010

� Springer Science+Business Media, LLC 2010

Although bariatric surgery effectively reduces the mortality

risk from obesity-related comorbidities [1, 2], it is associ-

ated with a 1–5% risk of anastomotic complications.

Anastomotic leaks have traditionally been treated with a

combination of drainage with long-term parenteral nutri-

tion or postanastomotic enteral nutrition, allowing the leak

to heal. Strictures at the gastrojejunostomy are initially

treated with repeated endoscopic dilation, but revisional

bariatric surgery is needed for refractory strictures with its

associated high complication rate. Chronic fistulas are

initially treated conservatively but often need high-risk

revisional surgery. Recently, endoscopic covered stents

have been used successfully for treatment of anastomotic

complications after esophageal resection [3–5]. Case series

evaluating stents to treat anastomotic leaks after Roux-en-

Y gastric bypass have shown success [6–9]. However, the

numbers of patients enrolled in these studies are small, and

only short-term outcomes are reported.

The primary aim of this study is to present long-term

healing rates after endoscopically placed covered stents in

the treatment of various anastomotic complications after

bariatric surgery. The secondary aim is to analyze symptom

improvement scores, complications, and factors affecting

stent migration.

Materials and methods

We performed a retrospective analysis of all patients

treated with endoscopic stents for staple-line complications

after bariatric surgery from January 2007 to January 2009.

The study was approved by the University of Missouri

Institutional Review Board.

Inclusion criteria were patients who underwent either

Roux-en-Y gastric bypass or sleeve gastrectomy with

subsequent anastomotic complications defined as acute

staple-line leaks, chronic anastomotic fistulas or refractory

anastomotic strictures. Acute leaks were defined as those

occurring within 1 month postoperatively. Refractory

anastomotic strictures were defined as persistent clinically

significant strictures that were endoscopically dilated more

than twice without resolution. Chronic fistulas were defined

as enterocutaneous or gastrogastric fistulas for longer than

1 month.

The stents were placed using both endoscopic and

fluoroscopic guidance with endoscopy being used to

delineate the area of leak, stricture or fistula. This pathol-

ogy was then marked with either a radiopaque marker on

the skin surface or by injecting water-soluble contrast in

the mucosa adjacent to the pathology to use as an internal

marker. Strictures were identified and dilated for at least

Presented at the SAGES 2009 Annual Meeting, April 22–24, 2009,

Phoenix, AZ.

Electronic supplementary material The online version of thisarticle (doi:10.1007/s00464-010-1203-y) contains supplementarymaterial, which is available to authorized users.

A. Iqbal � B. Miedema (&) � A. Ramaswamy � N. Fearing �R. de la Torre � C. Stephen � K. Thaler

Department of General Surgery, University of Missouri

Columbia, One Hospital Drive, MC 520E McHaney, Columbia,

MO 65212, USA

e-mail: miedemab@health.missouri.edu

A. Iqbal

e-mail: atifiqbal007@hotmail.com

Y. Pak

Office of Medical Research, University of Missouri Columbia,

One Hospital Drive, MC 520E McHaney, Columbia, MO 65212,

USA

123

Surg Endosc (2011) 25:515–520

DOI 10.1007/s00464-010-1203-y

1 min with an 18-mm balloon before stenting. A flexible

guide wire was passed through the endoscope and down the

Roux limb or duodenum, depending on whether a gastric

bypass or sleeve was performed. The endoscope was then

removed, and fluoroscopy was used to position the stent

across the leak or stricture using the guide wire and radi-

opaque marker to position the stent properly. Repeat

endoscopy was performed to assess the need for placement

of additional stents if adequate proximal or distal coverage

was not achieved or if angulation was encountered at the

ends of the stent. Figure 1 presents the most common

pattern of stent positioning by the end of the study.

Both nitinol (Alimaxx-ETM, Alveolus Inc, Charlotte,

NC) and polyester (PolyflexTM, Boston Scientific Inc,

Natick, MA) silicone-covered stents were used in this

series. The polyester stent comes in 16, 18, and 21 mm

diameters, with varying lengths of 9, 12 or 15 cm. The

deployment system has a 12–14 mm diameter. The nitinol

or metal based stents come in 18 and 22 mm diameters, but

in 10 or 12 cm lengths; the metal-covered stents come in a

7-mm delivery system that makes passage possible through

tighter strictures. We used more nitinol stents as the study

progressed due to its decreased migration rate.

The day after stent placement, an upper gastrointestinal

contrast study was done. If no leak was present, a diet was

started. Oral nutrition consisted of a high-protein liquid diet

identical to that started in postoperative bariatric surgery

patients. After hospital discharge, patients were seen weekly

and an abdominal radiograph was taken to confirm adequate

stent position. Patients who started having abdominal pain or

dysphagia were evaluated with esophagogastroduodeno-

scopy and upper gastrointestinal contrast study.

The primary outcome measured was resolution rate.

Anastomotic leak resolution was defined as absence of

contrast extravasation from the bowel after the stent was

removed. Stricture resolution was defined as ability to

tolerate a regular diet after stent removal with symptomatic

and radiological improvement. Secondary outcome mea-

sures included procedure time, symptomatic improvement,

type of stent used, complications, and migration rates.

Complications were defined as a significant deviation from

the expected course that resulted in morbidity such as

failure of stent therapy, recurrent stricture or fistula, stent

migration, mucosal incorporation, and stent fracture or

kinking requiring removal. Stent migration was defined as

either radiologic or endoscopic evidence of migration with

uncovering of the area of leak, stricture or fistula. Criteria

for placement of[1 stent was less than 5 cm overlap in the

distal esophagus, proximal jejunum or radiological leak of

contrast between two stents. A standardized telephone

questionnaire was administered to assess improvement in

symptoms in all patients. The questionnaire used a 0–10

score for symptoms such as chest pain, heartburn, dys-

phagia, regurgitation, abdominal pain, nausea/vomiting,

type of diet, and dietary tolerance. The questionnaire was

administered by the same physician in all patients.

The statistical analysis was performed using the Fisher’s

exact test for categorical variables, and the Kruskal–Wallis

test to compare distributional differences in continuous or

ordinal outcome measures. Pairwise comparisons among

three groups were conducted where significance was found

from the Kruskal–Wallis test. In these multiple pairwise

tests, p-values B0.01 were considered significant; for all

other tests, p-values B0.05 were considered significant.

The analysis was done using SAS version 9.2.

Results

Twenty-six patients (14 leaks, 6 strictures, 3 fistulas, 2

leaks followed by stricture, and 1 leak followed by fistula)

were treated with a total of 55 endoscopic stent procedures

(27 polyester, 28 nitinol). Mean age was 47 years (range

30–67 years), and there were 19 females and 7 males. The

procedures included Roux-en-Y bypass in 24 patients and

sleeve gastrectomy in 2 patients, with mean operative time

for stent placement of 56 min. Demographic characteristics

of the patient population are shown in Table 1.Fig. 1 Most common pattern of stent placement during the later part

of the study. Arrow marks site of leak

516 Surg Endosc (2011) 25:515–520

123

Oral feeding was started in 81% of patients within 24 h

of stenting. The stent was removed after a mean of 27, 18,

and 49 days for the leak, stricture, and fistula group,

respectively. All patients with strictures had considerable

pain after stent placement that led to its removal within

8 days, except for one patient who tolerated the stent for

15 weeks. Short-term postoperative outcomes are shown in

detail in Tables 2 and 3.

The overall complication rate for the 55 stent placement

procedures was 47% (Table 4). Stent migration was the

most common complication (40%). Migrated stents could

be retrieved endoscopically in 82% cases, and passed

through the entire gastrointestinal (GI) tract in 9%. Lapa-

roscopic stent removal for stent-related complications was

necessary in 4 out of the 55 stents placed (7%), with the

indication being stent migration in 2 patients (4%), stent

incorporation into bowel mucosa in 1 patient, and a lapa-

roscopic omental patch for enterotomy in the Roux limb

after endoscopic stent extraction in 1 patient. One of the

two patients requiring laparoscopic stent extraction for

migration had a stricture, while the other had a fistula.

There was no mortality.

The factors significantly affecting the migration rate are

shown. Migration rate was significantly lower for nitinol

stents, overlapping stents, polyester stents C15 cm, nitinol

stents C12 cm, and for the last 30 stents placed as com-

pared with the first 25 stents (Table 5).

Of the 55 stents placed, 5 were 16 mm, 13 were 18 mm,

and 37 were 22 mm in diameter. No correlation between

stent diameter and migration rate was seen. Also, stent

length was 90 cm in 7, 100 cm in 15, 120 cm in 24, and

150 cm in 9. However, many of these patients had over-

lapping stents, thus the functional length may have been

greater. The length of the individual stents did not correlate

with migration rates.

Symptomatic improvement occurred in 92% of patients

at long-term follow-up. Pre- and postoperative symptom

scores obtained by telephone questionnaire are compared

in Figs. 2 and 3 for patients with strictures and fistulas,

respectively. Patients with leaks underwent stent placement

emergently and had no baseline scores with which to

compare. Long-term outcomes ([1 year) are shown in

Table 6.

Resolution of leak, fistula or stricture after stent treat-

ment occurred in 22 of 26 patients (85%), at a mean of 46,

56, and 9 days for leak, fistula, and stricture, respectively.

Resolution was documented by radiographic imaging,

which occurred in the outpatient setting an average of

6 days after stent removal. A single stent procedure was

sufficient for either complete healing of the leak/fistula or

symptomatic improvement of the stricture in 12 patients

(46%). This included seven patients with leak, four with

stricture, and one with fistula. Fourteen patients required

two or more stenting sessions.

Four patients (15%) with leak (one), fistula (one) or

stricture (two) failed stent therapy. Two patients required

surgical intervention (one leak, one fistula). The leak

patient who failed was early on in our series and did not

undergo laparoscopic washout at the time of stent place-

ment despite evidence of abdominal contamination. Most

subsequent patients with leaks underwent laparoscopic

drainage with stent therapy unless the leak was diagnosed

within 24 h of initial surgery and no extraluminal collec-

tion was found on computed tomography (CT) scan. The

fistula patient was considered a failure after seven stent

placements were unsuccessful in healing the fistula and

reoperation was required. The two stricture patients who

failed stent therapy underwent two endoscopic dilations

after stent removal, with one patient tolerating a regular

diet at follow-up while the other continued to have inade-

quate fluid intake. Twenty-four patients (92%) were

Table 1 Demographic data of patients undergoing stent placement

for bariatric complications

Sex

(M:F)

Agea

(years)

Time of stent placement

after bariatric surgery

(weeks)a

Leak (n = 17) 7:10 49 \1

Stricture (n = 6) 0:6 46 70

Fistula (n = 3) 0:3 46 51

a Mean

Table 2 Short-term patient-related outcomes after initial stent

placement for bariatric complications (n = 26)

Mean time

stented (#)

Mean time to

healing (days)

Immediate

nutrition (%)

Leak (n = 17) 3 49 92

Stricture (n = 6) 1* 18 100

Fistula (n = 3) 4 56 50

* Group significantly different from the other two groups

Table 3 Short-term stent-related outcomes after stent placement for

bariatric complications (n = 55)

OR time

(min)

Mean days

stented

Complication

rate (%)

Migration

rate (%)

Leak (n = 17) 63 27 29* 37

Stricture (n = 6) 63 18* 50 18

Fistula (n = 3) 42 49 66 67

OR operating room

Complication rate includes failures and operative extraction of stents

for migration, incorporation or enterotomy but excludes stent

migration

* Group significantly different from the other two groups

Surg Endosc (2011) 25:515–520 517

123

tolerating a regular diet (exception of one stricture and one

fistula) at mean follow-up of 15 months. Both of these

patients were considered failures of stent therapy.

Discussion

In an earlier study we showed that endoscopically placed

covered stents contributed to healing and early oral intake

after anastomotic complications of bariatric surgery [9].

Stents support healing while allowing enteral nutrition,

improve symptoms, avoid morbid and costly procedures, and

significantly decrease hospital stay [9, 10] for these patients.

This study extends these findings with more patients and

longer follow-up. The initial good results are sustained for a

mean of 15 months for leaks, strictures, and fistulas. Stents

have become an integral part of care at our institution for

anastomotic complications after bariatric surgery.

A total of 17 patients were treated for acute anastomotic

leaks. We believe that stenting represents a clear

improvement of care in this patient group. Most did

extremely well. Although two patients developed stric-

tures, only one patient experienced long-term failure where

Table 4 Complications after

stent placementComplication No. of patients %

Patient-related complications (n = 26)

Failure of symptom resolution 4 15

Stricture after leak resolved 2 8

Fistula after leak resolved 1 4

Stent-related complications (n = 55)

Stent migration 22 40

Retrieved by endoscopy 18 33

Spontaneous passage through the GI tract 2 4

Laparoscopic extraction after failed trial of spontaneous passage 2 4

Others

Stent fracture requiring endoscopic removal 1 2

Stent kinking requiring endoscopic removal 1 2

Laparoscopic repair of enterotomy from stent removal 1 2

Laparoscopic extraction for mucosal incorporation after failed

attempts at endoscopic removal

1 2

Table 5 Factors affecting stent migration

Factor No. of

patients

Migration

rate (%)

p-Value

Stent type

Polyester 27 48 \0.005

Nitinol 28 32

Stent overlap

Single nitinol stent 14 38 \0.005

Overlapping nitinol stent 14 28

Stent length

Polyester stent \15 cm 14 54 \0.005

Polyester stent C15 cm 13 41

Stent length

Nitinol stent \12 cm 9 40 \0.005

Nitinol stent C12 cm 19 27

Learning curve

First 25 stents 25 64 \0.005

Last 30 stents 30 20

3

0

8

2

6

2

8

5

8

4

0

1

2

3

4

5

6

7

8

Dysphagia Reflux* Heartburn* Abdominalpain

Vomiting

Preop score

Postop score

* p < 0.05

Fig. 2 Comparison of mean pre- and postoperative symptom scores

for patients with stricture

518 Surg Endosc (2011) 25:515–520

123

the leak did not heal. This failure may have been prevented

by better mechanical clearing of abdominal contamination

at the time of the initial leak.

Treatment of strictures was not as uniformly successful.

The patients had significant pain after stenting, which

required stent removal at a median of 8 days after place-

ment. None of the patients have had revisional surgery, but

two of eight were considered failures due to the need for

further endoscopic dilation at a mean of 55 weeks. We

believe that stent therapy for strictures is beneficial and not

only decreases the need for revisional surgery but also the

number of endoscopic interventions required for symp-

tomatic control. So, in our experience, stent therapy has led

to a decrease in the number of interventions required for

symptomatic relief. The four patients treated by stenting

for fistula is a very limited experience. Three of the patients

did heal, while one required revisional surgery. Because of

the high risk of revisional surgery, we believe that stricture

and fistula patients are well served by a trial of stenting.

Migration away from the site of pathology continues to

be the major problem with endoscopic stenting as a treat-

ment modality [10]. With increased experience, we began

using longer and multiple overlapping stents. With this

strategy, our migration rate decreased to 27% (overlapping

covered nitinol stents) and we were able to approach the

migration rate for esophageal stents (24%), possibly due to

greater mucosal surface area in contact with the stents [3,

11–13]. Previous studies have shown that the main mor-

bidity of covered stents was migration while that for

uncovered stents was tissue ingrowth and difficult extrac-

tion [5, 6, 9]. Deployment of an uncovered stent within a

covered stent has been shown to reduce the migration rate

while avoiding tissue ingrowth [4]. These findings point to

the potential for slightly stiffer, less compliant, and longer

stents to help solve the problem of stent migration. The

nitinol (Alveolus) stents are designed with ‘‘antimigration’’

struts to minimize the amount of migration by inducing

impaling of the mucosa and providing better tissue

ingrowth. This may play a role in preventing migration.

Other techniques for stent fixation, including endoscopic

clip application or surgical suturing, failed in our hands.

We experienced a learning curve with the use of stents,

as evidenced by the lower migration rate (20%) with the last

30 stents. This can be attributed to refinements in technique,

attention to adequate coverage from the esophagus proxi-

mally to an adequately apposed segment of the jejunum

distally, willingness to deploy additional overlapping stents,

and use of longer stents to achieve the above purpose. It was

our impression that a larger-diameter stent decreased

migration rates. However, we did not have adequate num-

bers to demonstrate this conclusion statistically.

When migration occurs, it can usually be easily man-

aged. Most stents can be retrieved by upper endoscopy or

are passed through the GI tract. Surgical removal of the

migrated stent from the distal small bowel was only

required in two patients (8%), both with nitinol stents. This

is similar to the previously described rate in the literature.

Ko et al. reported on 888 patients with foregut stents

(including esophageal), with an 8% migration rate and a

4% surgical removal rate [7].

The optimal timing of stent duration is still unknown.

We did not see the problems that others have reported with

tissue hyperplasia at the ends of nitinol stents leading to

difficult extraction [14, 15]. We did have one patient who

required operative stent extraction due to mucosal incor-

poration after stenting for 16 weeks. Studies [14, 15] have

suggested routine stent removal no later than 6 weeks due

to the above-mentioned reason. Our current practice is to

leave stents in after leaks for 3–4 weeks. The time that

stents are left in for stricture is usually limited by

2

0

8

0

8

0

8

0

5

00

1

2

3

4

5

6

7

8

Dysphagia Reflux Heartburn Abdominalpain

Nausea

Preop score

Postop score

Fig. 3 Comparison of mean pre- and postoperative symptom scores

for patients with fistula

Table 6 Long-term outcome ([1 year) after stent placement for

bariatric complications

Mean

clinical

FU (weeks)

Mean

radiologic

FU (weeks)

Symptomatic

improvement

(%)

Failure

rate (%)

Leak (n = 17) 56 20 94* 6

Stricture (n = 6) 55 25 82 33

Fistula (n = 3) 89* 62* 75 33

FU follow-up

* Group significantly different from the other two groups

Surg Endosc (2011) 25:515–520 519

123

symptoms. Our preference is to leave them in for 8 weeks

if possible. Stents for chronic fistula are also left in 8 weeks

if tolerated well. Further studies are needed to better define

the optimal time for stent removal.

The strength of this study is that it is the largest clinical

experience with the longest follow-up for this patient

population to date, with encouraging outcomes. The pri-

mary weakness is the retrospective nature of the study.

Future studies are needed with long-term follow-up, espe-

cially in patients with strictures and fistulas, and also to

further elucidate the factors influencing stent migration.

Outcomes will likely be improved as stent manufacturers

customize stents for these indications.

Conclusions

Endoscopically placed covered stents are safe and effective

in treating acute leaks, chronic fistulas, and refractory

strictures after bariatric surgery. Covered stents are the

treatment of choice for acute leaks after bariatric surgery.

Stenting can provide rapid healing while simultaneously

allowing for oral nutrition and help prevent revisional

surgery in some patients with strictures. A small experience

suggests that stenting may contribute to healing for chronic

fistula. Stent migration, tissue ingrowth, and stent erosions

are problems and can potentially require surgical correc-

tion. There is room for improvement by the industry in

terms of stent design. We believe that use of endoscopi-

cally placed stents will become the preferred treatment for

bariatric patients with staple-line complications. Additional

studies are needed that address these complications and

occasional failures seen with stents.

Disclosures Authors Atif Iqbal, Brent Miedema, Archana Ra-

maswamy, Nicole Fearing, Roger DeLaTorre, Youngju Pak, Caleb

Steffen, and Klaus Thaler have no conflicts of interest or financial ties

to disclose.

References

1. Christou NV, Sampalis JS, Liberman M, Look D, Auger S,

McLean AP, MacLean LD (2004) Surgery decreases long-term

mortality, morbidity, and health care use in morbidly obese

patients. Ann Surg 240:416–423

2. Busetto L, Mirabelli D, Petroni ML, Mazza M, Favretti F, Segato

G, Chiusolo M, Merletti F, Balzola F, Enzi G (2007) Comparative

long term mortality after laparoscopic adjustable gastric banding

versus nonsurgical controls. Surg Obes Relat Dis 3:496–502

3. Radecke K, Gerken G, Treichel U (2005) Impact of a self-

expanding, plastic esophageal stent on various esophageal ste-

noses, fistulas, and leakages: a single-center experience in 39

patients. Gastrointest Endosc 61:812–818

4. Song GA, Kang DH, Kim TO, Heo J, Kim GH, Cho M, Heo JH,

Kim JY, Lee JS, Jeoung YJ, Jeon TY, Kim DH, Sim MS (2007)

Endoscopic stenting in patients with recurrent malignant

obstruction after gastric surgery: uncovered versus simulta-

neously deployed uncovered and covered (double) self-expand-

able metal stents. Gastrointest Endosc 65:782–787

5. Thompson AM, Rapson T, Gilbert FJ, Park KG (2004) Endo-

scopic palliative treatment for esophageal and gastric cancer:

techniques, complications, and survival in a population-based

cohort of 948 patients. Surg Endosc 18:1257–1262

6. Kim GH, Kang DH, Lee DH, Heo J, Song GA, Cho M, Yang US

(2004) Which types of stent, uncovered or covered, should be

used in gastric outlet obstructions? Scand J Gastroenterol

39:1010–1014

7. Ko HK, Song HY, Shin JH, Lee GH, Jung HY, Park SI (2007)

Fate of migrated esophageal and gastroduodenal stents: experi-

ence in 70 patients. J Vasc Interv Radiol 18:725–732

8. Salinas A, Baptista A, Santiago E, Antor M, Salinas H (2006)

Self-expandable metal stents to treat gastric leaks. Surg Obes

Relat Dis 2:570–572

9. Eubanks S, Edwards CA, Fearing NM, Ramaswamy A, de la

Torre RA, Thaler KJ, Miedema BW, Scott JS (2008) Use of

endoscopic stents to treat anastomotic complications after bari-

atric surgery. J Am Coll Surg 206:935–938

10. Fukumoto R, Orlina J, McGinty J, Teixeira J (2007) Use of

polyflex stents in treatment of acute esophageal and gastric leaks

after bariatric surgery. Surg Obes Relat Dis 3:68–72

11. Langer FB, Wenzl E, Prager G, Salat A, Miholic J, Mang T,

Zacherl J (2005) Management of postoperative esophageal leaks

with the polyflex self-expanding covered plastic stent. Ann

Thorac Surg 79:398–403

12. Hunerbein M, Stroszczynski C, Moesta KT, Schlag PM (2004)

Treatment of thoracic anastomotic leaks after esophagectomy

with self-expanding plastic stents. Ann Surg 240:801–807

13. Schubert D, Scheidbach H, Kuhn R, Wex C, Weiss G, Eder F,

Lippert H, Pross M (2005) Endoscopic treatment of thoracic

esophageal anastomotic leaks by using silicone-covered, self-

expanding polyester stents. Gastrointest Endosc 61:897–900

14. Eisendrath P, Cremer M, Himpens J, Cadiere GB, Le Moine O,

Deviere J (2007) Endotherapy including temporary stenting of

fistulas of the upper gastrointestinal tract after laparoscopic ba-

riatric surgery. Endoscopy 39:625–630

15. Song HY, Park SI, Do YS, Yoon HK, Sung KB, Sohn KH, Min

YI (1997) Expandable metallic stent placement in patients with

benign esophageal strictures: results of long-term follow-up.

Radiology 203:131–136

520 Surg Endosc (2011) 25:515–520

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