Duodenal obstruction following abdominal aortic surgery: case report

CASE REPORT

Duodenal obstruction following abdominal aortic surgery: case report

Adenauer Marinho de Oliveira Góes Junior^I; Alexandre Petnys^II; Edgar Rabboni^II; Milton Alves das Neves Junior^I; Paulo Henrique Petterle^III; Rafael Couto Melo^I; Tatiana Rocha Protta^I; Weverton Terci^III

^IPhysician. Resident, Vascular Surgery Service, Hospital do Servidor Público Municipal de São Paulo (HSPM), São Paulo, SP, Brazil.

^IIPhysician. Assistant, Vascular Surgery Service, HSPM, São Paulo, SP, Brazil.

^IIIVascular surgeon. Former resident, Vascular Surgery Service, HSPM, São Paulo, SP, Brazil.

ABSTRACT

Most articles on duodenal obstruction following aortic surgery report data relative to repairs of aneurysmal disease, not atherosclerotic disease. However, duodenal obstruction is an uncommon complication, occurring in less than 1% of patients. We report a case of a patient submitted to aortobifemoral bypass reconstruction who had duodenal obstruction as postoperative complication. The patient was treated with surgical intervention and omental patching for retroperitoneal synthesis. Literature review indicates that most cases respond well to the conservative treatment, and surgical conduct is usually only required when adherences are causing the obstruction or when clinical treatment is not satisfactory after 2 weeks.

Keywords: Occlusion, duodenum, surgery, aorta.

RESUMO

A maior parte dos artigos sobre obstrução duodenal após cirurgia aórtica cita dados referentes às correções da doença aneurismática e não da doença aterosclerótica. Não obstante, é consenso que se trata de uma complicação rara, cuja incidência é menor do que 1%. Os autores relatam o caso de um paciente submetido a enxerto aorto-bifemoral que apresentou, como complicação pós-operatória, oclusão duodenal. O paciente foi tratado com reintervenção cirúrgica e uso de remendo de grande omento para síntese do retroperitônio. A revisão da literatura indica que a maioria dos casos responde bem ao tratamento conservador, e a conduta cirúrgica normalmente só é necessária quando aderências são a causa da obstrução ou quando o tratamento clínico não é satisfatório após 2 semanas.

Palavras-chave: Oclusão, duodeno, cirurgia, aorta.

Introduction

Incidence of gastrointestinal complications following aortic surgery ranges between 6.6-21%. These complications are associated with increased risk of morbidity and mortality and often include paralytic ileus, upper digestive hemorrhage, Clostridium difficileenterocolitis, colon ischemia, pancreatitis, and acute cholecystitis.¹

Duodenal obstruction is a rare complication following abdominal aortic surgery; its incidence is lower than 1%.² Most cases described in the literature include patients treated for aneurysmal disease. Due to the rarity of such complication, diagnosis is frequently delayed, resulting in significant morbidity.

Case report

A 55-year-old male patient sought the vascular surgery clinic complaining of lower limb claudication for distances shorter than 50 m, including hip muscles. He also reported erectile dysfunction.

The patient reported history of smoking and alcoholism for a long time. He denied other comorbidities, but reported history of gastrectomy 16 years ago due to peptic ulcer and lumbar spine surgery using posterior access 7 years ago.

Femoral and distal pulses were not palpable on vascular examination. Digital angiography showed occlusion of the abdominal aorta immediately after renal artery ostia and refilling of the femoral and popliteal arteries (Figure 1).

The patient was submitted to aorto-bifemoral bypass using an 18 x 9 mm Dacron graft. Access to the retroperitoneum was difficult due to adherences in the abdomen supramesocolic segment attributed to previous surgery. The patient progressed uneventfully, and the diet was gradually normalized. He was discharged on the fifth postoperative day (PO).

On the 14 the PO the patient was admitted due to complaints of vomiting and abdominal pain, but maintained elimination of flatulence and feces.

The patient had lost weight, mild abdominal distension and diffusely painful abdomen on palpation, normal air-fluid levels and absence of pain on sudden decompression; surgical wounds remained in good condition, and distal pulses of the lower limbs were preserved. Diagnostic hypotheses were early adherences, intracavitary abscess or foreign body and colon ischemia.

Sigmoidoscopy of the rectum did not identify any sign if colonic ischemia, but computed tomography showed gastric distension image suggestive of stenosis of the third duodenal portion (Figure 2).

On the 23rd PO an upper digestive endoscopy was performed, inserting a nasoenteral probe until the transition from the second to the third duodenal portion. This topography showed "large reduction in lumen, but with no lesions."

Enteral feeding using a probe was started and the patient had no vomiting for 3 days; his abdomen remained with a tympanic sound on percussion and painful after diet administration.

Surgical reexploration was performed on the 27th PO. Laparotomy showed clamping of the third duodenal portion along the retroperitoneal suture.

This suture plan was partially undone; the retroperitoneum was opened; and the posterior wall of the third duodenal portion and graft were exposed (Figure 3). Duodenum release was completed with Kosher's maneuver, and duodenal transit was reestablished, as confirmed by intraoperative endoscopy.

The retroperitoneum was sealed with an omental patch, avoiding a new duodenal clamping and protecting the graft.

The patient was maintained in fasting and with a nasogastric probe until the third PO of surgical reexploration, when he had adequate air-fluid levels. Liquid feeding was started.

On the sixth PO, after progression and diet acceptance, the patient was discharged. He progressed well after a 6-month follow-up. He reports resolution of claudication and erectile dysfunction, with present and symmetrical distal pulses of the lower limbs. There were no digestive complaints.

Discussion

Although complications of abdominal aortic aneurysm surgery are well described in the literature, there is a lack of reports related to aortoiliac occlusive disease. Graft occlusion and anastomotic pseudoaneurysm are the main complications responsible for the need of reintervention.³

Gastrointestinal complications following aortic surgeries using transperitoneal access occurred in 6.6-21%of cases and are associated with large morbidity and increased mortality.¹ Paralytic ileus is the most common, present in 10% of cases. Upper digestive hemorrhage, Clostridium difficile enterocolitis and colonic ischemia are frequent.¹

The duodenum is the segment of the gastrointestinal tract that is more related to problems involving the abdominal aorta. Its retroperitoneal situation, nearly resting on the aorta, facilitates its involvement in many situations, such as aortoduodenal syndrome, described in 1905 by Sir William Osler, in which an aneurysm causes obstruction of the duodenum by compressing it against the superior mesenteric artery or against the abdominal wall itself.⁴

Aortoenteric fistula is another complication. This is the most severe event related to the digestive tract, but fortunately it is rare and affects less than 1% of patients.^3,5,6 A factor implied in aortoenteric fistula formation is the inappropriate graft cover by retroperitoneal tissue. Graft adherence to the duodenal wall, excessive pulsatility of a redundant graft, and graft colonization by Staphylococcus epidermidis strains are also considered as factors contributing to formation of fistulas.⁵

Duodenal obstruction following aortic surgery is a rare complication; its incidence is lower than 1%.² Campagnol et al. reports only 11 cases of intestinal obstruction following aneurysm repair described until 1996.¹ A more recent study reports that only 18 cases were described in the English-language literature from 1985 to 2004.²

Obstruction is usually manifested from the eighth to the 60th PO (mean 13.3 days).² Clinical status may include excessive and sometimes bilious vomiting, abdominal bloating, nausea, and abdominal pain.² Differential diagnosis includes paralytic ileus, digestive hemorrhage, duodenal neoplasm, pancreatitis,² intracavitary abscess or foreign body, and colon ischemia.

Among the mechanisms of duodenal obstruction reported so far are adherences, superior mesenteric artery syndrome, serum collection in the aneurysmal sac, compression due to retroperitoneal hematoma or due to the duodenal wall itself, and incorrect closure of the retroperitoneum.^1,2 A survey of 15 cases published from 1966 to 1994 showed that two patients underwent surgery due to occlusive aortic disease, and 13 due to aneurysms. In 10 of these cases, the most common mechanism of duodenal obstruction was formation of adherences.¹ Other studies reported retroperitoneal hematoma as the most frequent cause.¹

Occlusive disease surgeries normally require lower exposure of the aorta and, consequently, there is less duodenal manipulation.¹ In the reported case, as the aortic occlusion was juxtarenal, there was the need of dissection above the renal arteries. In addition, this patient had difficult access to the aorta due to the adherences resulting from the previous surgery (gastrectomy).

Treatment of duodenal subocclusion in the postoperative period of aortic procedures can be conservative or surgical.²

Early obstruction of small intestine loop requiring surgical intervention is generally followed by a 17% mortality and increased morbidity caused by intracavitary abscesses, surgical wound infection, formation of fistulas, eventration, and persistence of obstruction.²

Conservative conduct, based on use of gastric decompression, hydration and symptomatics, is able to avoid a new surgery in 73% of cases. When the obstruction is supposedly due to duodenal wall edema, endovenous corticotherapy using betamethasone 5 mg/day for 5 days is an option.¹ Total parenteral nutrition is also valid when fasting is maintained for a long time.² Although the period of treatment may range between 7-66 days, 83% of patients conservatively treated have their intestinal transit reestablished in 2 weeks.²

Investigation of the mechanism responsible for an obstruction is crucial to conduct the case.² Complementary examinations, such as computed tomography, contrast x-rays of the upper digestive tract^1,2 and endoscopy may help clarify which mechanism is involved in each case.

Conservative treatment is effective in most obstructions caused by compressions secondary to retroperitoneal, intramural hematomas or collections of the aneurysmal sac.² On the other hand, occlusions secondary to adherences and inappropriate closure of the retroperitoneum rarely respond to clinical measures.²

The surgical technique to be used is dependent on multiple factors, such as the obstruction mechanism, conditions typical of involved organs, and anatomical changes caused by previous surgeries, among others. Although there are options of digestive bypasses, such as gastrojejunal and duodenojejunal,¹ these should be avoided due to risk of aortic graft contamination, dehiscence of anastomoses and formation of fistulas. Simpler techniques, such as evacuation of retroperitoneal hematoma, lysis of adherences, and removal of an inappropriate suture of the retroperitoneum can sometimes be enough.

In case of retroperitoneum opening, efforts should be concentrated so that the aortic graft is not exposed, especially its proximal anastomosis, with the aim of preventing formation of aortoenteric fistulas. A new synthesis of the retroperitoneum can be performed, as long as there is enough tissue along the duodenum and in conditions that allow a new suture. Use of omental patch, interposed between duodenum and graft,^3,5,6 is also an option. In case such tactics is not possible, the omentum can be replaced by materials such as dura mater or bovine pericardium.

When the retroperitoneal synthesis is performed in the usual manner, the risk of aortoenteric fistulas is lower than 1%, and symptoms may appear between 8-180 months after graft insertion (mean 47 months).⁴

No data were found on the likelihood of having this complication when the retroperitoneum is closed with the aid of patches or on how long it would take to develop. There are also no references about vigilance protocols with periodic complementary examinations to try to anticipate occurrence of aortoenteric fistula.

References

• 1. Campagnol M, Di Giacomo M, Cruciani R, Cavallaro A. Duodenal obstruction following elective abdominal aortic aneurysm repair. Cardiovasc Surg. 1996;4:843-5.
• 2. Lin CY, Lin BY, Kang PL. Duodenal obstruction after elective abdominal aortic aneurysm repair: a case report. Kaohsiung J Med Sci. 2004;20:501-5.
• 3. Ruby BJ, Cogbill TH. Aortoduodenal fistula 5 years after endovascular abdominal aortic aneurysm repair with the Ancure stent graft. J Vasc Surg. 2007;45:834-6.
• 4. Adam DJ, Fitridge RA, Raptis S. Late reintervention for aortic graft-related events and new aortoiliac disease after open abdominal aortic aneurysm repair in an Australian population. J Vasc Surg. 2006;43:701-5; discussion 705-6.
• 5. Takagi H, Matsuno Y, Sekino S, Kato T, Umemoto T. Aortoduodenal syndrome. J Vasc Surg. 2006;43:851.
• 6. Armstrong PA, Back MR, Wilson JS, Shames ML, Johnson BL, Bandyk DF. Improved outcomes in the recent management of secondary aortoenteric fistula. J Vasc Surg. 2005;42:660-6.

Correspondence

Publication Dates

• Publication in this collection
  30 Jan 2009
• Date of issue
  Dec 2008

History

• Received
  20 May 2008
• Accepted
  08 Sept 2008