In an 80‑year‑old woman with massive maroon‑colored lower gastrointestinal bleeding, pale appearance, tachycardia, persistent hemorrhage despite adequate fluid resuscitation, and a soft non‑tender abdomen, what is the initial management?

Initial Management: CT Angiography

In this 80-year-old woman with massive maroon-colored lower GI bleeding, hemodynamic instability (tachycardia, pallor), and persistent hemorrhage despite resuscitation, CT angiography should be performed immediately as the first diagnostic step—NOT colonoscopy, NOT nasogastric tube placement, and NOT barium enema. 1, 2

Why CT Angiography is the Correct Answer

CT angiography (CTA) provides the fastest and least invasive means to localize active bleeding in hemodynamically unstable patients before any therapeutic intervention. 1, 2 The patient's shock index (heart rate/systolic BP) is likely >1 given her tachycardia and clinical presentation, which defines hemodynamic instability and mandates immediate CTA rather than endoscopy. 1, 2

Evidence Supporting CTA First:

• CTA has a 94% positive rate in hemodynamically unstable patients with lower GI bleeding 1
• Following positive CTA, catheter angiography with embolization should be performed within 60 minutes to maximize success rates 1, 2
• The British Society of Gastroenterology explicitly recommends AGAINST colonoscopy as the initial approach when shock index >1 or patients remain unstable after resuscitation 1

Why the Other Options Are Wrong

A. Nasogastric Tube (NGT) - INCORRECT

• NGT placement is useful only when an upper GI source is suspected, but this patient has maroon-colored stool suggesting a lower GI source 3, 1
• While 10-15% of patients with severe hematochezia have an upper GI source 1, the maroon color and soft non-tender abdomen make this less likely
• NGT should only be considered AFTER CTA rules out a lower GI source 1, 2

C. Colonoscopy - INCORRECT

• Colonoscopy is contraindicated as the initial approach in hemodynamically unstable patients 1
• Colonoscopy requires adequate bowel preparation, which this unstable patient cannot tolerate 3, 1
• Colonoscopy should be reserved for stable patients or performed AFTER successful localization and stabilization via angiography 1
• The patient is "continuing to bleed despite good resuscitation," indicating ongoing instability that precludes colonoscopy 1, 2

D. Barium Enema - INCORRECT

• Barium enema is absolutely contraindicated in acute GI bleeding as it obscures subsequent angiography and endoscopy
• This is an outdated diagnostic modality with no role in acute hemorrhage management

Management Algorithm for This Patient

Step 1: Confirm Hemodynamic Instability

• Calculate shock index (HR/systolic BP) - if >1, patient is unstable 1, 2
• This patient has tachycardia and pallor, indicating shock index >1 1, 2

Step 2: Continue Aggressive Resuscitation

• Maintain two large-bore IV lines (18-gauge or larger) 2
• Use restrictive transfusion thresholds: hemoglobin trigger 80 g/L (8 g/dL) with target ≥100 g/L given her age (80 years) and likely cardiovascular comorbidities 1, 2
• Correct coagulopathy immediately: fresh frozen plasma for INR >1.5, platelets for count <50,000/µL 3, 1, 2

Step 3: Immediate CTA

• Perform CTA immediately without delay 1, 2
• CTA detects bleeding at rates as low as 0.3 mL/min 3
• Do NOT wait for bowel preparation or attempt colonoscopy first 1

Step 4: Catheter Angiography with Embolization

• If CTA is positive, proceed to catheter angiography with embolization within 60 minutes 1, 2
• Angioembolization achieves immediate hemostasis in 40-100% of cases 3
• Embolization provides time to stabilize the patient and prepare the bowel, improving surgical outcomes if surgery ultimately becomes necessary 1

Step 5: Surgery Only as Last Resort

• Surgery is indicated ONLY if the patient remains unstable despite all localization and intervention attempts 3, 1
• Blind segmental resection carries rebleeding rates up to 33% and mortality of 33-57% 1, 2
• Emergency subtotal colectomy has mortality rates of 27-33% 1, 2

Critical Pitfalls to Avoid

• Never rush to colonoscopy in unstable patients—this delays definitive localization with CTA and potential embolization 1
• Never perform blind surgical resection without preoperative localization 1, 2
• Do not assume all maroon stools are lower GI—consider upper endoscopy if CTA is negative, as up to 11% may be from upper GI bleeding 1
• Mortality in lower GI bleeding is primarily related to comorbidities rather than exsanguination: overall in-hospital mortality is 3.4%, but rises to 20% in patients requiring ≥4 units of red cells 1, 2
• In this 80-year-old patient, postoperative mortality risk is approximately 9.8% if surgery becomes necessary 1