Gastroscopy – Essential Information Before the Procedure

Gastroscopy is a diagnostic procedure recommended in various clinical scenarios where an assessment of the upper gastrointestinal tract is necessary. Key indications for performing this examination include: persistent digestive symptoms such as heartburn, abdominal pain, nausea, vomiting, or a feeling of fullness after meals; suspicion of peptic ulcer disease; suspicion of gastrointestinal bleeding; presence of polyps in the digestive tract; difficulty swallowing (dysphagia); unexplained weight loss; and the need to evaluate postoperative changes in the gastrointestinal system (D. S. Early et al. 2012).

Gastroscopy is a relatively brief procedure that typically lasts between 10 and 30 minutes. Before commencing, the patient receives a local anesthetic spray to the throat, which helps alleviate discomfort and suppresses the gag reflex. If the patient experiences significant anxiety, the physician may administer an intravenous sedative. The patient lies on their left side with their head slightly elevated, which facilitates the insertion of the gastroscope and provides better access to the upper gastrointestinal tract. The doctor inserts a thin, flexible tube with a camera through the mouth, esophagus, into the stomach, and the duodenum. During the examination, the patient may be instructed to swallow or breathe in specific patterns to assist the movement of the endoscope. The physician observes the live feed from the camera to assess the condition of the esophagus, stomach, and duodenum. If necessary, tissue samples are taken for biopsy, or other procedures such as polyp removal are performed. After completion, the endoscope is carefully withdrawn, and the patient may experience temporary throat discomfort, which usually subsides quickly. Post-procedure, especially after sedation, the patient should rest and avoid driving (S. Pérez Romero et al., 2019).

Proper preparation for gastroscopy is essential to ensure diagnostic accuracy and minimize patient discomfort during the procedure.

Before undergoing gastroscopy, patients should adhere to specific dietary guidelines. They must refrain from eating for 6–8 hours prior to the procedure to ensure the stomach is completely empty during the examination. This allows the physician to thoroughly assess the mucosal lining of the digestive tract and minimizes the risk of complications, such as the aspiration of food particles into the airways. If the gastroscopy is scheduled for the morning, the last meal should be light and consumed no later than the evening before. It should consist of easily digestible foods containing minimal fat, as fat can delay gastric emptying. An appropriate dinner might include boiled chicken, rice, and steamed vegetables. Heavy, fatty, and gas-producing foods such as fried dishes, legumes, cabbage, broccoli, or carbonated beverages should be avoided. For gastroscopies scheduled later in the day, patients may have a light breakfast, but a 6–8-hour fasting period must still be observed before the procedure. The guidelines for this meal are the same as for a morning gastroscopy. Clear liquids, such as water or weak, unsweetened tea, are permitted up to 4 hours before the examination. These liquids are quickly absorbed by the body and leave no residue in the stomach. However, beverages that are difficult to digest or may leave sediment should be avoided, particularly coffee with milk, carbonated drinks, citrus juices, or high-sugar beverages. Approximately 4 hours before the procedure, all fluid intake should be discontinued to ensure the stomach is empty (Mayo Clinic 2024).

Prior to undergoing endoscopy, patients should thoroughly inform their physician about all medications they are taking to ensure proper preparation. Certain medications, particularly those affecting blood coagulation, may heighten the risk of complications during the procedure. In such instances, the physician may advise adjusting the dosage or temporarily discontinuing the medication for a few days before the examination to facilitate a safe and effective intervention. Antihypertensive medications are generally safe to take on the day of the test, preferably in the morning, accompanied by a small amount of water to maintain stable blood pressure. For antidiabetic medications, such as insulin or oral agents, the physician may modify the dosage or administration schedule to prevent hypoglycemia, especially when fasting is required before the procedure. It is also advisable to inform the physician about any dietary supplements, herbal remedies, or other preparations, as some may affect blood coagulation or interact with other medications. Providing a comprehensive list of all medications will enable the physician to take appropriate precautions to ensure the procedure is conducted smoothly and without complications (NHS 2022).

On the day of the gastroscopy, it is essential to abstain entirely from smoking conventional cigarettes, e-cigarettes, or tobacco heating devices. Nicotine and other compounds in cigarette smoke can stimulate excessive gastric acid secretion, potentially irritating the stomach lining. Furthermore, an excess of stomach acid impairs visibility during the procedure, making it challenging for the physician to accurately assess the digestive tract. This may result in less accurate findings, thereby affecting diagnostic precision and subsequent therapeutic decisions (W. Q. Yu et al., 2022).

Gastroscopy can induce anxiety in patients, particularly due to its invasive nature and concerns regarding potential discomfort. To mitigate these apprehensions, it is crucial that the patient is thoroughly informed about the examination process and possible sensations, such as transient throat discomfort or vomiting reflexes. Post-procedure, patients may also experience belching and bloating, which are entirely normal occurrences. Understanding what to anticipate at each stage often helps alleviate anxiety and facilitates mental preparation for the procedure (F. Behrouzian et al. 2017).

Gastroscopy is generally a safe procedure, but like any medical examination, it carries a certain risk of complications. The most common issue is temporary throat irritation, which may manifest as pain, hoarseness, or dryness, as well as vomiting during the examination. Local anesthesia typically helps alleviate these symptoms. More rarely, serious complications such as bleeding can occur, especially if a biopsy or polyp removal was performed during the test. In extremely rare cases, there may be a perforation of the stomach wall, which requires immediate medical intervention. There is also a slight risk of infection, which may present as fever and worsening pain. Some patients may experience allergic reactions to anesthetics or sedatives, which can manifest as rash, difficulty breathing, and in extreme cases, anaphylactic shock. After receiving sedatives, the patient may experience drowsiness, dizziness, or nausea for several hours post-procedure, so it is advised to avoid driving and strenuous physical activity. While gastroscopy is not the most pleasant procedure, it is minimally invasive, safe, and highly valuable for diagnosis, so it should be performed as soon as possible if indicated (Z. Nabi 2016).