Why do patients throw up dark blood after sleeve gastrectomy?

Why Patients Vomit Dark Blood After Sleeve Gastrectomy

Hematemesis (vomiting dark blood) after sleeve gastrectomy is an alarming clinical sign that predicts intra-abdominal complications requiring immediate diagnostic work-up and strong consideration for urgent surgical intervention. 1

Critical Immediate Assessment

When a patient presents with dark blood vomiting (hematemesis) post-sleeve gastrectomy, you must immediately evaluate for:

• Tachycardia ≥110 beats per minute - this is a main alarming sign requiring immediate action 1, 2
• Fever ≥38°C combined with tachycardia and tachypnea - this triad significantly predicts anastomotic or staple line leak 1, 2, 3
• Hypotension and decreased urine output - indicating hemorrhagic shock 1
• Respiratory distress - pulmonary embolism must be systematically excluded 1, 2

Primary Causes of Hematemesis Post-Sleeve Gastrectomy

1. Staple Line Bleeding (Most Common)

• The long stapler line is the most frequent source of bleeding, occurring in 1.7-1.9% of cases 4, 5
• Bleeding can present as hematemesis, hemoperitoneum, or both 4
• Dark blood (rather than bright red) suggests the bleeding has been present for hours, allowing gastric acid to convert hemoglobin to hematin 6, 4

2. Gastro-omental Artery Pseudo-aneurysm

• A rare but serious cause of delayed bleeding (typically 10-15 days post-op) 6
• Presents with hematemesis and hemorrhagic shock 6
• Requires CT angiography for diagnosis and arterial embolization for treatment 6

3. Marginal Ulcer

• Can develop in the early post-operative period 1, 2
• Presents with hematemesis and epigastric pain 1
• Diagnosed via endoscopy 2

4. Anastomotic/Staple Line Leak with Secondary Bleeding

• The combination of fever, tachycardia, and tachypnea predicts this complication 1, 3
• Infected hematomas can develop into late gastric leaks 4
• Conservative management of bleeding carries 50% risk of infected hematoma and potential late leakage 4

Diagnostic Algorithm

Step 1: Immediate Laboratory Assessment 1, 2

• Complete blood count (assess hemoglobin drop and white blood cell count)
• Serum lactate levels (elevated suggests ischemia, though can be normal in 90% of internal hernias)
• C-reactive protein (CRP) - highly sensitive for complications
• Procalcitonin
• Coagulation studies

Step 2: Imaging Studies 2, 6

• CT abdomen/pelvis with IV contrast (CT angiography if active bleeding suspected) - identifies hemoperitoneum, pseudo-aneurysms, and leaks
• Note: CT may be normal in 90% of internal hernia cases, so clinical suspicion must guide management 2

Step 3: Endoscopy 2

• Proceed with endoscopy as primary diagnostic tool for patients without septic signs
• Identifies marginal ulcers, anastomotic strictures, and intraluminal bleeding sources
• The American College of Surgeons recommends this approach 2

Management Strategy

If Septic Signs Present (Fever + Tachycardia + Tachypnea):

Proceed directly to urgent laparoscopic exploration - do not delay for endoscopy 1, 2, 3

• This triad significantly predicts anastomotic/staple line leak requiring immediate surgical intervention 2, 3
• Mortality correlates with delay in surgical intervention 1

If Hemodynamically Unstable Without Septic Signs:

• Resuscitate aggressively with crystalloids and blood products 6
• CT angiography to identify bleeding source 6
• Interventional radiology consultation for possible arterial embolization if pseudo-aneurysm identified 6
• Surgical consultation for laparoscopic exploration if bleeding cannot be controlled or source unclear 4, 5

If Hemodynamically Stable:

• Endoscopy first to identify and potentially treat intraluminal bleeding sources 2
• If endoscopy normal but symptoms persist, proceed to diagnostic laparoscopy 2
• Internal hernia can present with normal labs and imaging 2

Critical Pitfalls to Avoid

Do NOT attribute hematemesis to "normal post-operative course" - persisting vomiting and hematemesis are alarming clinical signs with high probability of serious complications 1, 2

Do NOT rely solely on laboratory values - in internal hernia cases, white blood count is normal in 68.75% and lactate is normal in 90% 2

Do NOT delay surgical exploration in patients with persistent symptoms and vital sign abnormalities - the World Journal of Emergency Surgery strongly recommends against delaying prompt diagnostic work-up and laparoscopic surgical exploration 1

Do NOT manage postoperative bleeding conservatively without close monitoring - 50% of conservatively managed bleeding cases develop infected hematomas, and 50% of those progress to late gastric leaks 4

Timing Considerations

• Early bleeding (0-7 days): Usually staple line bleeding, technical issues 4, 5
• Delayed bleeding (7-15 days): Consider pseudo-aneurysm formation 6
• Late presentation (>4 weeks): Consider marginal ulcer, though internal hernia remains most common late complication 2

The key principle is that any clinical signs of intestinal bleeding such as hematemesis after bariatric surgery are predictor signs of intra-abdominal complications and warrant aggressive investigation and management 1.