Lower GI bleeding Flashcards
What is the main problem in this clinical case?
The main problem is acute lower gastrointestinal (GI) bleeding, evidenced by repeated episodes of red blood per rectum (hematochezia).
What other issue needs to be questioned in this patient?
The patient’s orthostatic hypotension suggests hypovolemia due to blood loss.
What are the possible causes of lower GI bleeding in this patient?
Possible causes include diverticulosis, colorectal cancer, hemorrhoids, ischemic colitis, and angiodysplasia.
What is hematochezia, and what does it indicate?
Hematochezia is the passage of bright red blood per rectum, indicating lower GI bleeding.
What tests would you request to investigate lower GI bleeding?
Lab tests: Hemoglobin, hematocrit, MCV, BUN, creatinine. Imaging tests: CT scan with oral/IV contrast, angiography, colonoscopy.
What is the gold standard for diagnosing lower GI bleeding?
The gold standard is colonoscopy, which allows direct visualization of the bleeding source.
How do you prepare the colon for a colonoscopy?
The colon is prepared using 2-3 liters of polyethylene glycol solution.
What is the difference between bleeding from hemorrhoids and diverticulosis?
Hemorrhoids: Bright red blood, often seen on toilet paper. Diverticulosis: Dark red or maroon blood mixed with stools.
What is the significance of the patient’s hemoglobin and hematocrit levels?
The patient’s hemoglobin is 11.0 g/dL and hematocrit is 32%, indicating acute blood loss anemia.
What imaging test might show a ‘bite sign’ in diverticulosis?
Intestinal transit with a barium enema might show the ‘bite sign’ in diverticulosis.
When is a CT scan preferred over colonoscopy in lower GI bleeding?
A CT scan is preferred in cases of acute abdomen or when colonoscopy is contraindicated.
What is the management approach for acute lower GI bleeding?
Resuscitation with IV fluids and blood transfusion, followed by colonoscopy within 24 hours.
What is the management approach for non-acute lower GI bleeding?
Proper study with lab tests and imaging, followed by colonoscopy after colon preparation.
Why is age a factor in suspecting the cause of lower GI bleeding?
In patients >50 years, the likelihood of diverticulosis, colorectal cancer, or angiodysplasia increases.
What does ‘licking’ blood in hemorrhoids indicate?
‘Licking’ blood refers to bright red blood that drips or is seen on toilet paper.
What is the difference between left-sided and right-sided colon bleeding?
Left-sided colon bleeding presents with rapid bleeding and bright red blood. Right-sided colon bleeding presents with slower bleeding and darker blood.
What is the significance of the patient’s BUN and creatinine levels?
The BUN is 13 mg/dL and creatinine is 0.8 mg/dL, which are normal.
What is the role of angiography in lower GI bleeding?
Angiography is used to localize active bleeding and may allow for embolization.
What is the ‘apple core sign’ in imaging?
The ‘apple core sign’ indicates colorectal cancer causing narrowing of the colon.
When is colonoscopy contraindicated in lower GI bleeding?
Colonoscopy is contraindicated in cases of acute abdomen, perforation, or severe diverticulitis.
What is the significance of the patient’s MCV (Mean Corpuscular Volume) in this case?
The MCV is 90 fL, which is normocytic. This suggests that the anemia is due to acute blood loss rather than a chronic process.
What is the difference between hematochezia and melena?
Hematochezia: Bright red blood per rectum, indicating lower GI bleeding.
Melena: Black, tarry stools, indicating upper GI bleeding.
What is the role of a nasogastric tube (NG tube) in evaluating GI bleeding?
An NG tube can help determine if the bleeding is from the upper GI tract or lower GI tract.
What is the ‘double contrast’ technique in imaging, and when is it used?
The double contrast technique involves using both barium and air during imaging to better visualize the colon lining. It is used to detect polyps, tumors, or diverticula.
What is the most common cause of lower GI bleeding in older adults?
The most common cause is diverticulosis, followed by angiodysplasia, colorectal cancer, and hemorrhoids.
What is angiodysplasia, and how does it present?
Angiodysplasia is abnormal blood vessels in the GI tract, commonly in the cecum or right colon. It presents with intermittent, painless bleeding.
What is the significance of the patient’s orthostatic vital signs?
Orthostatic changes indicate hypovolemia due to acute blood loss, requiring prompt fluid resuscitation.
What is the role of a tagged red blood cell scan in lower GI bleeding?
A tagged RBC scan can help localize slow or intermittent bleeding that is not detected by other imaging methods.
What is the ‘apple core sign’ in colorectal cancer?
The apple core sign is a radiographic finding where a tumor causes narrowing of the colon lumen, resembling a bitten apple.
What is the management of diverticular bleeding?
Resuscitation: IV fluids and blood transfusion if needed.
Colonoscopy: To identify and treat the bleeding diverticulum.
Surgery: If bleeding is severe or recurrent.
What is the difference between internal and external hemorrhoids?
Internal hemorrhoids: Located above the dentate line, painless, and may cause bright red bleeding.
External hemorrhoids: Located below the dentate line, painful, and may cause thrombosis or swelling.
What is the role of stool tests in evaluating lower GI bleeding?
Stool tests can detect occult bleeding but are not specific for the source. They are more useful for screening rather than acute bleeding.
What is the significance of the patient’s lack of abdominal pain?
The absence of abdominal pain suggests that the bleeding is not due to ischemic colitis or inflammatory bowel disease.
What is the role of a flexible sigmoidoscopy in lower GI bleeding?
A flexible sigmoidoscopy can visualize the rectum and distal colon but is less comprehensive than a colonoscopy.
What is the ‘watermelon stomach’ (gastric antral vascular ectasia)?
‘Watermelon stomach’ is a condition where the stomach lining has vascular lesions resembling watermelon stripes.
What is the role of proton pump inhibitors (PPIs) in lower GI bleeding?
PPIs are not typically used for lower GI bleeding unless there is suspicion of upper GI bleeding.
What is the significance of the patient’s denial of weight loss?
The absence of weight loss makes colorectal cancer less likely but does not rule it out entirely.
What is the role of a fecal immunochemical test (FIT) in lower GI bleeding?
FIT detects human hemoglobin in stool and is used for colorectal cancer screening.
What is the management of hemorrhoidal bleeding?
Conservative management: High-fiber diet, hydration, and stool softeners.
Procedures: Rubber band ligation, sclerotherapy, or surgery for severe cases.
What is the role of a capsule endoscopy in lower GI bleeding?
Capsule endoscopy is used to evaluate the small intestine for sources of obscure GI bleeding.
What is the significance of the patient’s normal BUN:creatinine ratio?
A normal BUN:creatinine ratio suggests that the bleeding is not from the upper GI tract.
What is the role of a Meckel’s scan in lower GI bleeding?
A Meckel’s scan detects ectopic gastric mucosa in a Meckel’s diverticulum, which can cause bleeding.
What is the significance of the patient’s lack of family history of colon cancer?
The absence of a family history reduces the likelihood of hereditary colorectal cancer syndromes.
What is the role of a digital rectal exam (DRE) in lower GI bleeding?
A DRE can detect anal fissures, hemorrhoids, or masses in the rectum.
What is the significance of the patient’s upright and supine vital signs?
The orthostatic changes indicate volume depletion due to acute blood loss.
What is the significance of the patient’s heart rate and blood pressure changes when upright?
The increase in heart rate (96 to 118) and drop in blood pressure (124/90 to 110/72) when upright indicate orthostatic hypotension, a sign of hypovolemia due to acute blood loss.
What is the role of a complete blood count (CBC) in evaluating lower GI bleeding?
A CBC helps assess the severity of blood loss (low hemoglobin and hematocrit) and determines if the anemia is acute (normal MCV) or chronic (low or high MCV).
What is the significance of the patient’s baseline hemoglobin (14 g/dL) compared to the current hemoglobin (11 g/dL)?
The drop from 14 g/dL to 11 g/dL indicates acute blood loss anemia, as the body has not had time to compensate for the bleeding.
What is the role of coagulation studies in lower GI bleeding?
Coagulation studies (e.g., PT, INR, PTT) help rule out coagulopathy as a contributing factor to the bleeding, especially in patients on anticoagulants or with liver disease.
What is the significance of the patient’s denial of prior GI diseases?
The absence of prior GI diseases (e.g., inflammatory bowel disease, peptic ulcers) suggests that the bleeding is likely due to a new condition, such as diverticulosis or angiodysplasia.
What is the role of a fecal calprotectin test in lower GI bleeding?
Fecal calprotectin is a marker of intestinal inflammation and can help differentiate between inflammatory bowel disease (elevated levels) and other causes of bleeding (normal levels).
What is the significance of the patient’s normal creatinine level?
A normal creatinine level (0.8 mg/dL) suggests that the patient’s kidney function is intact and that there is no significant prerenal azotemia due to hypovolemia.
What is the role of a small bowel follow-through in lower GI bleeding?
A small bowel follow-through is used to evaluate the small intestine for sources of bleeding, such as tumors or Crohn’s disease, when other tests are inconclusive.
What is the significance of the patient’s age (70 years) in the context of lower GI bleeding?
In patients >50 years, the most common causes of lower GI bleeding are diverticulosis, angiodysplasia, and colorectal cancer. Age increases the likelihood of these conditions.
What is the role of a CT enterography in lower GI bleeding?
CT enterography provides detailed images of the small intestine and can detect tumors, inflammatory lesions, or vascular abnormalities that may cause bleeding.
What is the significance of the patient’s denial of change in bowel habits?
The absence of changes in bowel habits (e.g., diarrhea, constipation) makes inflammatory bowel disease or colorectal cancer less likely but does not rule them out entirely.
What is the role of a balloon-assisted enteroscopy in lower GI bleeding?
Balloon-assisted enteroscopy allows for direct visualization and biopsy of the small intestine, which is useful for diagnosing obscure GI bleeding.
What is the significance of the patient’s normal BUN level?
A normal BUN level (13 mg/dL) suggests that the bleeding is not from the upper GI tract, where blood breakdown would increase BUN levels due to protein absorption.
What is the role of a wireless capsule endoscopy in lower GI bleeding?
Wireless capsule endoscopy is used to evaluate the small intestine for sources of obscure GI bleeding that are not detected by colonoscopy or upper endoscopy.
What is the significance of the patient’s denial of abdominal pain?
The absence of abdominal pain makes ischemic colitis or inflammatory bowel disease less likely, as these conditions typically present with pain.
What is the role of a rectal exam in lower GI bleeding?
A rectal exam can detect anal fissures, hemorrhoids, or rectal masses, providing clues to the source of bleeding.
What is the significance of the patient’s normal MCV (90 fL)?
A normal MCV indicates normocytic anemia, which is consistent with acute blood loss rather than chronic anemia (which would be microcytic or macrocytic).
What is the role of a fecal occult blood test (FOBT) in lower GI bleeding?
FOBT detects hidden blood in the stool and is used for colorectal cancer screening, but it is not useful in acute bleeding.
What is the significance of the patient’s upright and supine vital signs?
The orthostatic changes (increased heart rate and decreased blood pressure) indicate volume depletion due to acute blood loss, requiring urgent resuscitation.
What is the role of a Meckel’s diverticulum scan in lower GI bleeding?
A Meckel’s scan detects ectopic gastric mucosa in a Meckel’s diverticulum, which can cause bleeding, especially in younger patients.
What is the significance of the patient’s lack of family history of colon cancer?
The absence of a family history reduces the likelihood of hereditary colorectal cancer syndromes (e.g., Lynch syndrome or familial adenomatous polyposis).
What is the role of a digital rectal exam (DRE) in lower GI bleeding?
A DRE can detect anal fissures, hemorrhoids, or masses in the rectum, providing clues to the source of bleeding.
