Gastrointestinal (GI) endoscopy is a cornerstone diagnostic and therapeutic tool in modern medicine, enabling direct visualization, diagnosis, and treatment of disorders affecting the gastrointestinal tract. It encompasses upper GI endoscopy (esophagogastroduodenoscopy, EGD) and lower GI endoscopy (colonoscopy). Endoscopic procedures have revolutionized the management of GI diseases, providing minimally invasive alternatives to surgery while allowing biopsy, polyp removal, and therapeutic interventions.

While generally safe, gastrointestinal endoscopy requires careful preparation and awareness of potential risks to ensure optimal outcomes.

Types of Gastrointestinal Endoscopy

Upper GI Endoscopy (EGD)

Involves insertion of a flexible endoscope through the mouth to visualize the esophagus, stomach, and duodenum.

Indications include dyspepsia, gastroesophageal reflux disease (GERD), peptic ulcers, varices, gastrointestinal bleeding, and suspicion of malignancy.

Lower GI Endoscopy (Colonoscopy)

The endoscope is inserted through the rectum to examine the colon and terminal ileum.

Common indications are screening for colorectal cancer, evaluation of chronic diarrhea, constipation, bleeding, polyps, inflammatory bowel disease, and diverticulosis.

Specialized Endoscopy

Includes endoscopic retrograde cholangiopancreatography (ERCP), endoscopic ultrasound (EUS), and capsule endoscopy for detailed evaluation of the biliary system or small intestine.

Preparation for Gastrointestinal Endoscopy

Preparation is critical to ensure clear visualization, patient safety, and procedural success.

Fasting

Upper GI endoscopy: Patients are usually required to fast for 6–8 hours to minimize aspiration risk.

Lower GI endoscopy: Requires bowel cleansing using laxatives, enemas, or a combination, typically starting a day before the procedure.

Medication Management

Patients should inform the endoscopist of current medications, including anticoagulants, antiplatelets, diabetes medications, and blood pressure drugs.

Temporary adjustment or discontinuation of certain drugs may be required to reduce bleeding risk during biopsy or polyp removal.

Medical History and Consent

The endoscopist evaluates comorbid conditions such as heart disease, lung disease, kidney disease, or allergies.

Informed consent is obtained after discussing the purpose, procedure, alternatives, benefits, and potential risks.

Sedation and Anesthesia

Most endoscopic procedures are performed under conscious sedation or moderate sedation using medications like midazolam or propofol.

Patients should arrange for transport home after sedation, as they are temporarily impaired.

Clothing and Accessories

Patients are advised to wear comfortable, loose clothing and remove jewelry or dentures that may interfere with the procedure.

The Procedure
Upper GI Endoscopy

Patient lies on the left side, with monitoring of heart rate, oxygen saturation, and blood pressure.

A local anesthetic spray may be applied to the throat to reduce gag reflex.

The flexible endoscope is inserted through the mouth and gently advanced through the esophagus, stomach, and duodenum.

The endoscopist examines the mucosa, identifies abnormalities, and may take biopsies or perform therapeutic interventions like dilatation, variceal ligation, or foreign body removal.

Colonoscopy

Patient lies in the left lateral position with knees bent.

The colonoscope is inserted through the rectum and advanced carefully through the colon.

Air or carbon dioxide is insufflated to improve visualization.

Polyps can be removed, strictures dilated, and tissue samples taken for histopathology.

Risks and Complications

Although gastrointestinal endoscopy is generally safe, certain risks must be considered:

Common Minor Risks

Sore throat, mild abdominal discomfort, bloating, or cramping after the procedure.

Temporary drowsiness from sedation.

Bleeding

May occur after biopsy or polyp removal. Usually mild and self-limiting but occasionally requires intervention.

Perforation

Rare but serious. The endoscope can cause a tear in the GI tract, requiring surgical repair.

Risk is slightly higher in therapeutic procedures like polypectomy or dilation.

Cardiorespiratory Complications

Sedation may cause low blood pressure, slow heart rate, or breathing difficulty, especially in patients with underlying heart or lung conditions.

Infection

Extremely rare due to strict sterilization protocols, but post-endoscopy infections can occur in immunocompromised patients.

Allergic Reactions

Reactions to sedatives, local anesthetics, or latex are uncommon but possible.

Post-Procedure Care

Patients are monitored until the effects of sedation wear off.

Mild bloating or throat discomfort is normal and usually resolves within a day.

Instructions are provided regarding diet, activity, and follow-up.

Any alarming symptoms like severe abdominal pain, persistent bleeding, vomiting, or fever should prompt immediate medical attention.

Conclusion

Gastrointestinal endoscopy is a safe and effective procedure for diagnosing and managing a wide range of GI disorders. Proper preparation, including fasting, bowel cleansing, and medication adjustment, ensures optimal visualization and safety. While complications are uncommon, patients should be aware of potential risks such as bleeding, perforation, sedation-related issues, and infection.

With careful planning, skilled endoscopists, and adherence to safety protocols, GI endoscopy remains a minimally invasive, high-yield procedure that significantly improves patient care and outcomes.