8 Upper gastrointestinal and bariatric surgery

Approximately 80–85% of upper gastrointestinal haemorrhage stops spontaneously and only conservative therapy is needed. The remaining 15–20% require surgical intervention.^1,2 Upper gastrointestinal endoscopy is the first-line treatment for bleeding peptic ulcer. Various endoscopic methods are available, including injection of adrenaline into the ulcer, and the use of clips, thermoprobe, or laser.

Indications for surgical intervention are:^1–4

The position of the ulcer should ideally be identified with endoscopy prior to surgical intervention. The gastroduodenal artery runs along the posterior aspect of the first part of duodenum and thus a posterior wall ulcer must be assumed to involve this artery. An upper midline incision is made. In the case of duodenal ulcers a longitudinal pyloroduodenotomy is made. The gastroduodenal artery is under-run proximally and distally. A third suture may be inserted to control the transverse pancreatic branch of the artery. The pyloroduodenotomy is closed transversely (Fig. 8.1).

In the case of gastric ulcers the management depends on the size and position of the ulcer. Smaller ulcers may be sufficiently managed with under-sewing of the bleeding vessel. Very large ulcers may warrant a subtotal gastrectomy.⁴ Sufficient biopsies should be taken of gastric ulcers in order to exclude malignancy.

The patient may require intensive care unit (ITU)/high-dependency unit (HDU) care postoperatively depending on their comorbidities. They will also have a nasogastric tube and intra-abdominal drains in situ.

Achalasia is a condition that causes reduced peristalsis of the oesophagus and a high lower oesophageal sphincter (LOS) pressure. The purpose of surgery is to reduce the LOS pressure by dividing the muscle wall, without breaching the inner mucosa. The oesophageal wall consists of overlying adventitia, longitudinal and circular muscles, the muscularis propria layer followed by the submucosa and innermost mucosal layer. A longitudinal incision is made through the adventitia and muscle layers down to submucosa, starting above the LOS and extending down onto the stomach for approximately 3–7cm. This is now most commonly performed laparoscopically, although classically it was an open procedure. An endoscope may be introduced to ensure mucosal integrity on completion of the procedure.

A partial fundoplication may also be performed to prevent excessive acid reflux.

A feeding jejunostomy may be used as a route to provide enteral feed when it is not possible to administer food via the oesophagus or stomach or where supplemental oral intake is required. Oral feeding may not be possible due to pathology in the oesophagus or stomach, or following recent surgery with an oesophageal anastomosis.¹ Jejunal feeding is also usually employed in patients with neurological deficits.

A small midline incision is made above the umbilicus and a loop of jejunum identified and delivered though the wound. A fine-bore feeding tube is inserted into the lumen of the jejunum. The tube is then fed through the abdominal wall and a fixation device is attached to the skin. This procedure can also be performed laparoscopically.

This procedure is broadly divided into a subtotal or total gastrectomy and can be performed laparoscopically or as an open procedure. An upper midline incision is made for open procedures. In a total gastrectomy the entire stomach is removed and an anastomosis fashioned between the distal oesophagus and a jejunal loop forming a Roux-en-Y reconstruction, leaving a blind duodenal stump. The same reconstruction is performed in a subtotal gastrectomy with the jejunal loop being anastomosed onto the remaining stomach (Fig. 8.2). This is otherwise known as a Bilroth II procedure. In a Bilroth I procedure enough upper duodenum remains to anastomose directly onto the stomach.

Most gastrectomies are performed for gastric cancer. Segmental resection of the stomach can also be performed, for example, in the resections of gastrointestinal stromal tumours. In these procedures the stomach wall is closed primarily and no anastomosis is fashioned.

Patients undergoing gastrectomy need careful preoperative assessment and often require HDU care in the initial postoperative period. Patients may have abdominal drains, a nasogastric tube and/or a urinary catheter in situ in the immediate postoperative period. Depending on their comorbidities they may also require invasive monitoring such as CVCs and arterial cannulation.

Bariatric surgical procedures are divided into malabsorptive procedures and restrictive procedures. Restrictive procedures primarily reduce stomach size, and malabsorptive procedures, while they may also reduce the size of the stomach, primarily act to reduce absorption of ingested food. The commonest bariatric procedure, laparoscopic adjustable gastric banding, is an example of a restrictive procedure. Newer techniques include the sleeve gastrectomy and duodenal switch procedure. Gastric bypass surgery is an example of a mixed restrictive and malabsorptive procedure.

Gastric bypass surgery can be performed either open or laparoscopically. The stomach is divided into a small (∼30mL) proximal pouch and a large distal remnant pouch. The gastrointestinal tract is then reconstructed to allow drainage of both segments of stomach via a Roux En-Y reconstruction. This leads to a marked reduction in the functional volume of the stomach and an alteration in the physiological response to food.

These procedures are used to repair a sliding hiatus hernia or to treat some forms of intractable gastro-oesophageal reflux disease. There are many different types of wrap described. Nissen's is a 360° wrap of fundus around the oesophagus. Other partial wraps (170–270°) have also been described.^1–3 The partial wrap is intended to reduce postoperative dysphagia and bloating.

Prior to undergoing either type of procedure, various investigations need to be undertaken. Preoperative upper gastrointestinal endoscopy is required to assess for oesophagitis or the presence of hiatus hernia. For patients with reflux, oesophageal pH and manometry studies are required to detect the presence and severity of acid reflux, and to detect abnormal contractility of the oesophagus, which may preclude surgical correction.⁴ For example, in achalasia, there is abnormal contractility of the LOS and symptoms would not improve and may well deteriorate post-fundoplication.

The procedure is most commonly performed laparoscopically with the patient placed in a modified lithotomy position. The right and left crura are dissected and circumferential dissection of the oesophagus is performed. The hiatus is then closed with sutures. The short gastric vessels may be divided to improve mobilization of the fundus. In Nissen's procedure the mobilized fundus is wrapped 360° around the oesophagus by passing it through the posterior window behind the oesophagus. The wrap is then secured in place on the anterior oesophagus with a varying number of sutures. In a Watson procedure the wrap is wrapped anteriorly through 120° and secured anteriorly (Fig. 8.3).

Bariatric surgical procedures are grossly divided into malabsorptive procedures and restrictive procedures. Restrictive procedures primarily reduce stomach size, and malabsorptive procedures, while they may also reduce the size of the stomach, primarily act to reduce absorption of ingested food. Laparoscopic adjustable gastric banding is an example of a restrictive procedure.

In laparoscopic adjustable gastric banding an inflatable silicone band is placed around the fundus of the stomach. This produces a proximal pouch of stomach, which can hold approximately 120g of food. The band slows the passage of food into the remainder of the stomach and the stomach registers as full, giving the patient a sensation of early satiety. The band is connected to a subcutaneous port in the abdominal wall to allow inflation and deflation of the band. This allows the optimum ‘tightness’ of the band to be achieved, i.e. the level which produces optimum weight loss with an acceptable level of side effects.

Oesophageal perforation, while rare, is life-threatening, and 90% of cases are secondary to instrumentation of the oesophagus during endoscopy. The remaining 10% are due to Boerhaave's syndrome (oesophageal rupture secondary to vomiting or retching), trauma, or caustic injury secondary to ingestion of substances such as bleach.¹

Perforations can occur in the neck (cervical), the chest, or in the abdomen. Management depends on the level of the perforation. Diagnosis can be made by direct visualization at endoscopy, water-soluble contrast studies or during contrast CT scanning.²

This condition is usually dealt with by the ENT department. The perforations are most often treated conservatively but surgical repair may be recommended in the early stages. Later the tissues become friable where only drainage is possible.

Primary repair may be possible in the early stages. In cases of extreme contamination or late intervention, treatment consists of removal of contamination, copious washout, mediastinal drainage, and insertion of a T-tube into the defect. The use of a T-tube creates a controlled fistula.

These are most commonly iatrogenic secondary to surgery. When noted intraoperatively they can be repaired immediately. If they are detected postoperatively, a upper midline laparotomy is required for primary oesophageal repair and peritoneal washout.

The conduit of choice for oesophageal reconstruction is the stomach. However, if the stomach is not available, for example after a total gastrectomy or if pathology involves the stomach and oesophagus, another conduit will be necessary. The commonest indication for this is caustic injury of the oesophagus and stomach. For short defects a free jejunal interposition may be possible, however, larger defects require the colon.

Colonic interposition involves the fashioning of three anastomoses (Fig. 8.4). Ascending or transverse colon is used depending on the length required. The ascending colon is mobilized as an iso-peristaltic loop with a vascular pedicle formed from the middle colic vessels. The caecum is anastomosed to the cervical oesophagus in the neck or the thoracic oesophagus in the chest, forming an oesophagocolic anastomosis. To restore gastrointestinal continuity an ileocolic or colojejunal anastomosis is fashioned.¹

Jejunal grafts can be used as an iso-peristaltic interposition graft, however, its blood supply limits how high within the thoracic cavity it can be used. If it is required above the level of the aortic arch a vascularized free flap is required. This is technically a much more difficult procedure but may be physiologically preferable and therefore only used where other options are not possible or have failed. An oesophagojejunal anastomosis is fashioned in the chest followed by a jejuno-jejunal anastomosis to restore continuity.²

The conduit can be brought up into the neck via the posterior mediastinal, retrosternal, or subcutaneous route. The preferred route is the anatomical route, posterior mediastinal. However if this is not possible alternative routes may become necessary.

The commonest indication for oesophagectomy is malignant disease, however, occasionally it is needed for benign tumours or strictures. Oesophagectomy may be total or subtotal. The conduit for oesophageal replacement is usually the stomach but colon or vascularized small bowel may be used. Anastomosis may be in the neck or within the thorax. Access to the abdomen is required to mobilize the stomach (or other replacement organs¹).

Ivor Lewis oesophagectomy involves gastric mobilization and right thoracotomy with intrathoracic oesophagogastric anastomosis. Transhiatal oesophagectomy involves transhiatal mobilization of the oesophagus and oesophagogastric anastomosis via an incision in the neck. Three-stage McKeown oesophagectomy involves laparotomy, thoracotomy, and neck incision with oesophagogastric anastomosis in the neck.

Minimally invasive techniques, thoracoscopy, and laparoscopy are being used in all of the procedures mentioned.

OGD is a telescopic examination that is used for direct visualization of the oesophagus, stomach, and the first and second parts of the duodenum (Fig. 8.5). Upper gastrointestinal endoscopy may be diagnostic or therapeutic; emergency or elective. Common indications include gastrointestinal bleeding, dysphagia, vomiting, weight loss, epigastric pain, and reflux symptoms. Various procedures can be performed during an OGD, for example:

A paraoesophageal hiatus hernia is uncommon. The gastro-oesophageal junction remains within the abdomen and the stomach herniates beside it into the mediastinum. Repair is usually performed laparoscopically, however, it may be performed via an upper midline incision.¹ The stomach, other herniated contents, and the hernial sac are returned to the abdomen. The hernial sac can then either be circumcised or excised. The widened hiatal defect is then closed with non-absorbable sutures. A fundoplication is then performed to prevent postoperative reflux disease.

For very large defects (>10cm) a mesh may be required as it is not possible to close the crura adequately. The mesh is stapled to the underside of the diaphragm.

Before the advent of laparoscopic surgery, if a patient was asymptomatic it was felt that the risk of surgery outweighed the benefit, especially in elderly patients. However, it is now thought that with a minimally invasive procedure it is a more acceptable risk given the chance of strangulation or volvulus. However, if the patient does not wish to undergo surgery it would be acceptable to monitor symptoms and re-discuss intervention if there is any deterioration.

PEG is a method of introducing a feeding tube through the abdominal wall into the stomach for enteral feeding. An endoscope is passed into the stomach and used to transilluminate the abdominal wall. Insufflation distends the stomach and digital pressure is applied to the abdominal wall, which can be visualized indenting on the stomach by the endoscopist.

The PEG tube consists of a silicone tube and a 2cm disc-shaped ‘bumper’, which abuts the gastric wall. A fine-bore needle is introduced and can be seen entering the stomach on endoscopy; a feeding suture is then passed in through this needle and pulled up through the oesophagus and out through the mouth. The gastrostomy catheter is attached to the feeding suture and pulled down into the stomach. This catheter is passed through the stomach and abdominal wall under direct vision (Fig. 8.6).

Perforated peptic ulcer is a common cause of peritonitis requiring emergency surgery. Operation is usually via a midline laparotomy, however, surgery can be carried out laparoscopically.^1,2 Small acute duodenal perforations may be closed primarily, but more commonly an omental patch is used to plug the defect.

Perforated gastric ulcers may be malignant so it is important to obtain biopsies. If small, the ulcer may be excised or an omental patch applied. For larger gastric lesions, some form of gastrectomy may be required.

Bariatric surgical procedures are divided into malabsorptive procedures and restrictive procedures. Restrictive procedures primarily reduce stomach size and malabsorptive procedures, while they may also reduce the size of the stomach, primarily act to reduce absorption of ingested food. Sleeve gastrectomy is an example of a restrictive procedure. It is often used as a bridge procedure in high-risk patients prior to definitive weight loss procedures such as a duodenal switch.

Sleeve gastrectomy is a partial longitudinal gastrectomy. It removes the entire greater curvature of the stomach leaving a gastric volume of approximately 100mL, which drains directly into the duodenum without need for anastomosis. It can be performed laparoscopically or via an upper midline incision.

Splenectomy may be required in the treatment of haematological disorders, trauma, or in the case of massive splenomegaly to control symptoms and prevent injury.

Splenectomy is associated with long-term risk of infection so patients require preoperative immunizations where possible and will require lifelong antibiotics prophylaxis.¹ In traumatic splenic injury, splenic conservation should be considered at the time of laparotomy. Splenectomy may be performed laparoscopically or via a left subcostal or upper midline incision.²

• This is dependent on the indication for the surgery; medical treatment for haematological conditions is usually exhausted prior to consideration of surgery. In the case of trauma, spleen-preserving procedures are preferred where possible

Vagotomies are used in the treatment of peptic ulcer disease and their purpose is to abolish vagal stimulation of the parietal cells, thereby decreasing gastric acid secretion.¹ Highly selective vagotomy is rarely performed today as proton pump inhibition can virtually obliterate all gastric acid secretion. Indications for highly selective vagotomy include treatment of complications of increased acid secretion despite proton pump inhibitor treatment and non-compliant patients. This procedure can be performed laparoscopically or via an upper midline incision.