Upper gastrointestinal bleeding overview

# Overview
Upper gastrointestinal bleeding (UGIB) is defined as bleeding from the gastrointestinal tract that originates proximal to the ligament of Treitz. The most common causes of UGIB are peptic ulcer disease and esophageal varices. Clinical presentation includes overt bleeding from the gastrointestinal tract, rapid or slow, either manifested by hematemesis of fresh (blood-streaked to frankly bloody) or old ('coffee ground') vomitus, and/or melena. Initial management of UGIB includes an assessment of the patients hemodynamic status and repletion of lost intravascular volume, if needed. Diagnosis is most often made during upper endoscopy, which is usually performed within 24 hours of presentation,; sooner in patients who may be actively bleeding or who are hemodynamically unstable. Treatment is most often a combination of medical and endoscopic therapy. Prognosis depends on the cause of bleeding and the patients overall condition. Mortality from nonvariceal bleeding is 10%; Mortality from variceal bleeding is 20%. Despite advances in gastric acid suppression and endoscopic diagnosis and therapy, mortality rates have remained stable.

# Historical Perspective
Alessandro Benedetti was the first to give a detalied description of stomach in 1947. In 1543, Vesalius, a Belgian anatomist was the first to describe the anatomy of the esophagus. In 1682, D Zollikofer was the first to perform sclerotherapy by injecting an acid into a vein to induce thrombus formation. Asklepios was the first to describe association between GI bleeding and peptic ulcer disease.

# Classification
According to the American Gastroenterological Association, upper GI bleeding can be classified based on the rate of blood loss into overt(acute), occult or obscure(chronic) forms.

# Pathophysiology
The main inciting event in the pathogenesis of upper GI bleeding is damage to mucosal injury. This mucosal injury can occur at various levels of GI tract. If the damage and bleeding is confined upto ligament Treitz, it is defined as upper GI bleeding. Regardless of etiology, if the balance of gastric acid secretion and mucosal defenses is disrupted, acid interacts with the epithelium to cause damage leading to hemorrhage.

# Causes
There are many causes of upper GI hemorrhage. Causes are usually anatomically divided into their location in the upper gastrointestinal tract, which could either be esophageal (esophageal varices) or gastric (gastric ulcer) or duodenal e.g. duodenal ulcer. Patients are also usually stratified into having either variceal or non-variceal sources of upper GI hemorrhage, as the two have different treatment algorithms and prognosis. Other causes could be from infectious diseases, medication side effects, trauma or malignancy.

# Differentiating UGIB from Other Diseases
The various causes responsible for UGIB include peptic ulcer disease, esophagitis, gastritis/gastropathy, esophagogastric varices, ectopic varices, portal hypertensive gastropathy, angiodysplasia, dieulafoy's lesion, gastric antral vascular ectasia, Mallory-Weiss syndrome and upper GI tumors and must be differentiated from one another.

# Epidemiology and Demographics
About 75% of patients presenting to the emergency room with GI bleeding have an upper source. The diagnosis is easier when the patient has hematemesis. In the absence of hematemesis, 40% to 50% of patients in the emergency room with GI bleeding have an upper source. The incidence of acute UGIB is approximately 50 to 100 per 100,000 individuals worldwide. Patients of all age groups may develop upper gastrointestinal bleeding. Males are more commonly affected by UGIB than females.

# Risk Factors
Common risk factors in the development of upper gastrointestinal bleeding include advancing age, previous history of gastrointestinal bleed, chronic kidney disease, underlying cardiovascular disease, cirrhosis and portal hypertension, presence of H.pylori infection, NSAID's or aspirin use in patients with a history of ulcer disease, patients on dual antiplatelet therapy and patients of 60 years or older.

# Screening
There is insufficient evidence to recommend routine screening for upper GI bleeding.

# Natural History, Complications, and Prognosis
If left untreated upper gastrointestinal bleeding can become life-threatening. Massive blood loss can result in a severe drop in blood pressure resulting in decreased blood supply to organ systems leading to death. Complications of UGIB include end-organ damage and iron-deficiency anemia. Prognosis is generally good with prompt treatment, and the 1-year mortality rate of patients with nonvariceal UGIB is approximately 10%.

# Diagnosis

## Diagnostic study of choice
Upper GI Endoscopy is the gold standard test for the diagnosis of upper gastrointestinal bleeding. The American Society for Gastrointestinal Endoscopy guidelines recommends that upper gastrointestinal endoscopy is performed within 24 hours of presentation in all patients with UGIB. Endoscopy serves not only as a diagnostic tool in the localization of bleeding but also enables the use of therapeutic options, which include embolization or vasopressin infusion.

## History and Symptoms
Patients with upper GI hemorrhage often present with hematemesis, coffee ground vomiting, melena, maroon stool, or hematochezia if the hemorrhage is severe. The presentation of bleeding depends on the amount and location of hemorrhage. Patients may also present with complications of anemia, including chest pain, syncope, fatigue and shortness of breath. Obtaining the history is the most important aspect of making a diagnosis of upper GI bleed. It provides insight into the cause, precipitating factors and associated comorbid conditions and also helps in determining the severity of the bleed as well as in identifying the potential source of bleed.

## Physical Examination
Patients with chronic upper GI bleeding usually appear fatigue, on contrast depending upon the amount of blood loss, patient appear in distress and shock in acute upper GI bleeding.

## Laboratory Findings
In patients with acute Upper GI bleeding who are unstable rapid assessment and resuscitation should be initiated even before diagnostic evaluation. Once hemodynamic stability is achieved, a proper clinical history, physical examination, and initial laboratory findings are crucial not only in determining the likely sources of bleeding but also in directing the appropriate intervention. In acute GI bleeding, initial hematocrit level measured will not accurately reflect the amount of blood loss. Laboratory findings of chronic upper GI bleeding include anemia, coagulopathy, and an elevated BUN-to-creatinine ratio.

## Electrocardiogram
There are no specific ECG findings associated with upper gastrointestinal bleeding. However, an electrocardiogram is be performed in order to exclude arrhythmia and cardiac causes of hypotension (following acute MI).

## X-ray
There are no abdominal x-ray findings associated with upper gastrointestinal bleeding. However, an x-ray may be helpful in the diagnosing the complications of underlying disease. Findings of abdominal X-ray in perforated viscus associated with UGIB include free air under the diaphragm.

## Ultrasound
There are no echocardiography/ultrasound findings associated with upper gastrointestinal bleeding. However, ultrasound can be helpful in establishing portal vein patency prior to transjugular intrahepatic portosystemic shunt (TIPS) placement in patients with variceal bleeding.

## CT scan
Abdominal CT is not the study of choice in the evaluation of acute upper gastrointestinal bleeding. However, a CT can be helpful in the detection of UGIB from pseudoaneurysms of the mesenteric vessels, branches of the celiac axis and masses of the upper GI system or liver tumors.

## MRI
There are no MRI findings associated with upper gastrointestinal bleeding. Similar to CT, MRI has no real role in the assessment of acute upper gastrointestinal bleeding. MRI can be only helpful in depicting small visceral pseudoaneurysms or masses.

## Other Imaging Findings
In cases where the source of bleeding is unidentified after upper endoscopy, the utilization of subsequent diagnostic modalities depends upon the hemodynamic stability of the patient. Other imaging studies include CT angiography, catheter angiography, radionuclide imaging.

## Other Diagnostic Studies
Nasogastric lavage and UpperGI endoscopy are other diagnostic studies that are helpful in the diagnosis of upper gastrointestinal bleeding. Evidence of old (brown colored or 'coffee grounds') or fresh blood documents on nasogastric lavage indicates the presence of UGIB.

# Treatment

## Medical Therapy
In patients with acute Upper GI bleeding who are unstable rapid assessment and resuscitation should be initiated even before diagnostic evaluation. The initial steps in the management of a patient with UGIB is to assess the severity of bleeding, and then institute fluid and blood resuscitation as needed. Once hemodynamic stability is achieved, a proper clinical history, physical examination, and initial laboratory findings are crucial not only in determining the likely sources of bleeding but also in directing the appropriate intervention. Equilibration between the intravascular and extravascular spaces is not complete until 24 to 72 hours after bleeding has occurred. Nasogastric lavage should be performed if the presence or source of bleeding is unknown. Upper gastrointestinal endoscopy is the primary diagnostic tool, performed for both diagnosis and treatment of active bleeding. The American Society for Gastrointestinal Endoscopy guidelines recommends upper endoscopy within 24 hours of presentation in all patients with UGIB. Angiography and tagged erythrocyte scan are rarely needed but may be used to diagnose active UGIB, particularly in patients where EGD is contraindicated. Also, upper gastrointestinal tract radiographic studies using barium are generally not advised, as they may obscure visualization during EGD. Upper gastrointestinal bleeding is a medical emergency and requires prompt treatment. According to the American Society of Gastroenterology guidelines, the recommended medications include PPI's, octreotide and antibiotics. Pharmacotherapy is only used as an adjuvant therapy for all patients with UGIB.

## Surgery
Surgery is the last resort in the management of upper GI bleeding. Surgical options include TIPS, balloon tamponade, and emergency laparotomy. In UGIB, diagnostic and therapeutic endoscopy is be performed simultaneously. Therapeutic upper gastrointestinal endoscopy should be performed in all patients with suspected UGIB to evaluate and possibly treat the source of bleeding. The urgency of endoscopy depends on the anticipated source of bleeding, rapidity of blood loss, and hemodynamic stability of the patient. The common procedures used to manage upper GI bleeding caused by the peptic ulcer disease and esophageal varices are sclerotherapy (EIS), coagulation (thermal, electric, and argon plasma), hemostatic clips and variceal band ligation.

## Primary Prevention
Effective measures for the primary prevention of upper GI bleeding include administration of PPI in patients with an increased risk due to critical illness or use of NSAIDs or aspirin. In patients with cirrhosis and suspected portal hypertension, who found to have esophageal varices patients are given prophylactic treatment with a nonselective -blocker or undergo endoscopic variceal ligation (EVL) with surveillance endoscopy.

## Secondary Prevention
Effective measures for the secondary prevention of UGIB include discouraging the use of NSAIDS in all patients with a history of UGIB. For patients who are at high risk for rebleeding (elderly patients; those taking anticoagulant and antiplatelet medications), indefinite use of a PPI may be recommended. A combination of nonselective -blockers plus EVL is the best option for secondary prophylaxis of UGIB from varices.