CHAPTER 21 Common surgical procedures of the gastrointestinal tract
Gastrointestinal (GI) surgery is a vast topic encompassing many different techniques. These procedures can be performed by the traditional open surgery or more and more commonly laparoscopically (keyhole). Whether surgery is open or laparoscopic, the procedures should remain the same.
The range of operations in upper GI surgery can be conveniently divided into benign and cancer surgery. This is in contrast to lower GI surgery where the same operations are performed for both benign and neoplastic conditions. The aim for this chapter is to give the reader a broad idea of what is involved in each procedure.
The principle of cancer surgery is to remove the tumor completely with histologically proven margins and the lymph nodes that drain the tumor. Histologically, completeness of tumor clearance from the resection margins is classified R0, R1and R2. An R0 resection is defined as one where all margins are histologically free of tumor. An R1 resection is defined as one in which microscopic residual disease has been left behind. An R2 resection is defined as incomplete resection with macroscopic residual disease.
Reconstruction: historically, the continuity was usually reconstructed by carrying out a simple gastrojejunostomy. This can result in significant biliary reflux which can cause anastomotic ulcerations. A roux-en-Y reconstruction negates biliary reflux and is generally the preferred option of reconstruction (Figures 21.1A, 21.1B).
Figure 21.3 (A) Roux-en-Y, gastric bypass (note resection margins A and B); (B) roux-en-Y reconstruction. Resection margin ‘A’ forming a jejunojejunostomy; resection margin ‘B’ anastomosed to gastric pouch.
Antireflux surgery has a number of variations; however, the two gold standard procedures were described by the German surgeon Rudolph Nissen (1896–1981) and the French surgeon Andre Toupet born in 1915. Nissen’s fundoplication is a complete (360 degrees) wrap with the fundus round the lower esophagus and Toupet’s fundoplication is one where the fundus wraps the posterior aspect of the lower esophagus, variations suggest between 180 and 270 degrees (Figures 21.4 A–F).
Figure 21.4 (A) Wide diaphragmatic hiatus (1–2), gastric herniation (3); (B) gastric herniation reduced and the hiatus repaired. A retro-esophageal tunnel is created to allow for fundoplication; (C) gastric fundus pulled through to the right of the esophagus; (D) the Nissen 360 degrees wrap created by suturing points ‘A’ and ‘B’; (E) Nissen wrap at barium swallow; (F) the alternative Toupet 270 degrees wrap can be created by suturing points ‘A’ and ‘B’ to the sides of the esophagus.
Postoperative barium appearance: the lower esophagus is slightly narrowed by the wrap and the esophagus may have a bird’s beak appearance. Barium often has a slight delay before passing into the stomach.
Procedure: this procedure is carried out laparoscopically. A longitudinal incision down to but not beyond the mucosa is made in the lower esophagus extending into the gastric cardia. The smooth muscle is parted preventing it from forming a ring when contracted. Many patients will suffer from gastro-esophageal reflux following this and a partial fundoplication is often performed to reduce this.
Indication: perforated duodenal or gastric ulcer. With the introduction of H2 antagonist (e.g. ranitidine) and proton pump inhibitors (e.g. omeprazole), ulcer surgery, like highly selective vagotomy, has been consigned to history books. Modern day ulcer surgery is refined to emergency surgery for perforated or bleeding ulcers.
Procedure: this procedure is carried out laparoscopically. Gastric and duodenal ulcers may bleed or perforate. A gastrectomy should be considered if there is suspicion that the gastric ulcer may be malignant. Otherwise a wedge excision of the ulcer can be performed with the stomach wall simply repaired.
Torrential bleeding from duodenal ulcers are almost always sited posteriorly with the gastroduodenal artery involved. The duodenum is opened and the bleeding ulcer is under-run with sutures to ligate the bleeding vessel. With perforation, the perforation may be closed primarily or plugged by using the greater omentum.
The most common small bowel procedure is the small bowel resection. However, where small bowel conservation is paramount, such as when the patient is at risk of developing short gut syndrome from Crohn’s disease, strictureplasty is the surgery of choice.