Appendix 1. Glossary of terms

Ampullary carcinoma: a cancerous growth that occurs at the ampulla of Vater. This is the area in the small bowel where the biliary system drains into the gastrointestinal tract.

Anastomosis: a surgical connection (join) between two tubular structures. In a gastrojejunostomy, the anastomosis is between the stomach (gastric) and jejunum (small bowel).

Anastomotic leak: the breakdown in the join between two structures. This results in leakage of the contents of the structures into the abdominal cavity resulting in significant problems.

Anatomical position: the standard position of a structure when the body is in the standing position, facing forwards, and has not been altered by a disease process.

Benign: refers to conditions that are not cancerous.

Bile duct: the tubular structures that drain bile (greenish liquid that is necessary for the digestion and absorption of fat) from the liver and gallbladder to the small bowel.

Biliary obstruction: blockage of the bile ducts due to any cause, which includes cancers. This typically results in jaundice (yellowing of the skin).

Bolus: a ball‐like mixture of food and saliva that forms in the mouth during the process of chewing.

Carbon dioxide: a colourless gas with a density approximately 50% higher than that of dry air. This gas is typically used in key‐hole surgery to insufflate the abdominal cavity.

Cholangiocarcinoma: a cancer (malignant growth) of the bile ducts.

Comorbidities: the presence of one or more additional diseases or disorders that may affect the overall health of the person.

Conscious sedation: a technique in which the use of a drug or drugs produces a state of depression of the central nervous system, but with maintenance of verbal contact throughout.

Distal: the area that is at the bottom end. For example: the distal end of the stomach is the bottom end of the stomach.

Duodenum: the first part of the small bowel that begins after the stomach.

Electrolyte imbalance: a change in the concentration of salts in the blood (e.g. potassium, sodium), which are essential for normal cellular function. For example, this can occur after vomiting.

Epigastrium: describes the area of the body that sits below the chest in the centre. Epigastric pain refers to pain that is felt in this area.

Endoscope: the instrument used to look inside the stomach and small bowel during an endoscopy. It consists of a hollow tube, about the size of your fifth finger, with a light and camera. Instruments can be passed down the tube to take tissue samples from the stomach and small bowel.

Endoscopy: the process of looking inside the body with a camera attached to a scope. In gastroscopy, the camera is inserted via the mouth to the stomach and small bowel.

Fluoroscopic: relates to the radiological technique that uses specialised dye and x‐ray. It is typically used to monitor the placement of devices, including stents, in the body as it allows exact placement to be monitored.

Gastric: refers to the stomach.

Gastric outlet: the area of the stomach through which food passes on its route to the small bowel. The gastric outlet is in the part of the stomach that is known as the pylorus.

Gastric outlet obstruction (GOO): describes the obstruction to the passage of food and liquid at the distal end of the stomach, also known as the gastric outlet.

Gastrojejunostomy: describes a connection between the stomach (gastric) and small bowel (jejunum).

Helicobacter pylori: this is the name given to the bacteria that has been shown to be associated with peptic ulcer disease.

Intraluminal: refers to the inside of a hollow structure.

Jaundice: the yellow discolouration of the skin that can occur as a result of reduced drainage of bile (or biliary obstruction).

Jejunum: the middle part of the small bowel that is distal to the duodenum.

Laparoscopic: this is also referred to as minimal access or key hole surgery. This is surgery via small incisions on the abdomen through which specialised instruments are passed. This alleviates the need for large incisions on the abdomen.

Lateral: a term used to describe the position of a structure or object. Lateral describes objects or structures to the side, whereas, medial describes objects or structure lying along the middle or centre.

Lymphoma: a cancer that affects the lymph nodes of the body.

Malignant: refers to a cancerous process.

Metastatic disease: a disease that has spread from the organ that it originates from to lymph nodes or other organs around the body. Metastatic disease typically refers to an advanced stage of cancer.

Migration: the movement from the original position to another position. In stent migration refers to movement of the stent from the position it was placed to a different, and typically worse, position.

Morbidity: complications or events that impact on the persons’ ability to function and return to their normal level of functioning. For example, a chest infection that prevents walking is said to have caused morbidity.

Mortality: death rate.

Occlusion: blockage. This can be partial or complete.

Palliation: the control of symptoms without the treatment of, or attempt to treat, the underlying cause of the symptoms.

Pathological: the result of the underlying disease process.

Peptic ulcer: a break or erosion in the lining of the stomach or small bowel.

Perforation: a small hole that appears in part of the gastrointestinal tract as a cause of disease or an intervention. For example, a gastric perforation is a hole in the stomach from which stomach contents can escape into the rest of the abdominal cavity.

Perioperative: at the time of operation. For example; a perioperative complication would be something that occurs during the operation.

Physiological reserve: refers to the capacity, predominantly in terms of heart and lung function, that a person has to withstand various insults to the body.

Pneumoperitoneum: in laparoscopic surgery, carbon dioxide is placed inside the abdomen to create space. This is known as a pneumoperitoneum.

Port: a port is a specialised device used in laparoscopic surgery through which the specialised instruments are passed. A port is either 5 mm or 12 mm in size and, thus, the incisions are approximately this size.

Postprandial: occurs following eating.

Proton‐pump Inhibitor (PPI): a medicine that reduces the production of acid in the stomach. This helps to treat ulcers in the stomach.

Pylorus: the name given to the distal end of the stomach where the gastric outlet sits. A pyloric carcinoma is a cancer that grows at the pylorus.

Roux‐en‐y anastomosis: this describes a surgically created end‐to‐side anastomosis, usually between the stomach and small bowel.

Self‐expanding metal stent (SEMS): a stent that expands to fit the person depending on the space and external forces encountered.

Stent: a hollow tube, either plastic or metal, or self‐expanding, which is used to keep a passageway within the body open.

Terminal: refers to conditions for which there is no cure and for which this will be the cause of death. This does not mean that the symptoms cannot be treated or improved.

Umbilicus: the area at the belly‐button or navel.

Appendix 2. CENTRAL search strategy

1. exp Gastric Outlet Obstruction/

2. ((gastric or gastro* or stomach or pyloric) adj5 (obstruction* or obstructed or stenosis or stenoses or stricture* or narrow*)).tw,kw.

3. "GOO".tw,kw.

4. or/1‐3

5. exp Stents/

6. stent*.mp.

7. (SEMT or SEMTs).tw,kw.

8. exp Palliative Care/

9. (palliative or palliation).tw,kw.

10. or/5‐9

11. 4 and 10

Appendix 3. MEDLINE Ovid search strategy

1. exp Gastric Outlet Obstruction/

2. ((gastric or gastro* or stomach or pyloric) adj5 (obstruction* or obstructed or stenosis or stenoses or stricture* or narrow*)).tw,kw.

3. "GOO".tw,kw.

4. or/1‐3

5. exp Stents/

6. stent*.mp.

7. (SEMT or SEMTs).tw,kw.

8. exp Palliative Care/

9. (palliative or palliation).tw,kw.

10. or/5‐9

11. 4 and 10

12. randomized controlled trial.pt.

13. controlled clinical trial.pt.

14. random*.ab.

15. placebo.ab.

16. trial.ab.

17. groups.ab.

18. or/12‐17

19. exp animals/ not humans.sh.

20. 18 not 19

21. 11 and 20

Appendix 4. Embase Ovid search strategy

1. exp stomach obstruction/

2. ((gastric or gastro* or stomach or pyloric) adj5 (obstruction* or obstructed or stenosis or stenoses or stricture* or narrow*)).tw,kw.

3. "GOO".tw,kw.

4. or/1‐3

5. exp stent/

6. stent*.mp.

7. (SEMT or SEMTs).tw,kw.

8. exp palliative therapy/

9. (palliative or palliation).tw,kw.

10. or/5‐9

11. 4 and 10

12. (random: or placebo: or double‐blind:).mp.

13. clinical trial:.mp.

14. blind:.tw.

15. or/12‐14

16. exp animal/ not human/

17. 15 not 16

18. 11 and 17