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382 Duodenal Atresia and Stenosis

The most important differential diagnosis is duodenal obstruction
due to malrotation, resulting in volvulus of the midgut loop or extrinsic
compression related to Ladd´s bands across the duodenum. When no
prenatal diagnosis is available, contrast radiography may be helpful to
differentiate between these entities and can demonstrate the absence of
the normal C-shaped curve of the duodenum or a classic “bird’s-beak” Annular pancreas
shape secondary to a volvulus. When the diagnosis still remains in across duodenum
doubt, prompt laparotomy is warranted because undiagnosed volvulus
can result in gangrene of the entire midgut within hours.
If available, in cases of incomplete obstruction, oesophagogastro-
duodenoscopy (EGD) can be done to prove the existence of an intrinsic
obstructing membrane. An endoscopic approach to membrane resection
can be utilized.
Management
Preoperative Care
The intensity of preoperative care is typically proportionate to the
time from birth until hospital presentation. Initial therapy consists of
nasogastric decompression and appropriate replacement of fluid and
electrolytes. Most of these newborn patients are premature and small
for their gestational age, so special care must be taken to preserve body
heat and to avoid hypoglycaemia, especially in cases of very low birth
weight, congenital heart disease, and respiratory distress syndrome.
When incubators are unavailable, the “kangaroo” method of nursing
these children offers the best hope for survival. Figure 62.2: Annular pancreas with underlying duodenal stenosis.
General Intraoperative Considerations
General anaesthesia with endotracheal intubation is required. The most
commonly utilized incision is a muscle-cutting, transverse, right upper
quadrant incision. However, some centres are now employing minimal
access laparoscopic methods for repair of duodenal obstruction.
A side-to-side duodenoduodenostomy is the standard repair for
duodenal stenosis, atresia, or obstruction due to a preduodenal portal
vein. In 1977, Kimura and colleagues described a modification of this
procedure, known as the diamond-shaped duodenoduodenostomy. In
4
this technique, a horizontal incision is made across the distal aspect of
the proximal, dilated bowel, and a lengthwise incision is made along
the proximal aspect of the distal, small-calibre bowel. This can achieve
a greater diameter of the anastomosis for better emptying of the upper
duodenum. In some cases, duodenojejunostomy can be an alternative
and may afford an easier repair with minimal dissection. The choice of
surgical procedure is largely based on the preference of the surgeon.
When an annular pancreas associated with duodenal obstruction is
encountered (Figure 62.2), the treatment of choice is performance of
a duodenoduodenostomy between the segments of duodenum above
and below the area of the ring of pancreas. One should never consider
division of the pancreatic ring because that could result in a pancreatic
fistula while the underlying stenosis or atresia of the duodenum would
remain unchanged.
In the case of an endoluminal membrane, duodenotomy and
resection of the membrane can be done after localisation of the ampulla
of Vater. Alternatively, bypass of the membrane can be performed via a
duodenoduodenostomy, if desired. As seen in Figure 62.3, fenestrated
membranes may be amenable to an endoscopic approach to resection in
centres where this facility is available. 5

Operative Details Figure 62.3: Endoscopic view of duodenal web before and after endoscopic
Once the abdomen is entered, the hepatic flexure of the colon is mobil- dilatation and fenestration of the membrane.
ised. The duodenum is adequately mobilized by a Kocher manoeuvre.
The ligament of Treitz is divided as needed. A transpyloric tube passed
via the nose or mouth is helpful at this stage. Air or saline can be
passed into the second part of duodenum to assess the nature and level
of obstruction.
The dilated proximal duodenum and collapsed distal duodenum are
approximated by using stay sutures.