Summary

An anastomotic leak is a breakdown or failure of a surgical connection (anastomosis) between two parts of the bowel or other hollow organs, allowing contents to leak into the abdominal cavity. Think of an anastomosis as two pipes being joined together—when this connection fails, the contents leak out, causing peritonitis (inflammation of the abdominal lining), sepsis, and potentially death if not treated promptly. Anastomotic leaks are serious complications that can occur after bowel surgery (most common), esophageal surgery, or other procedures involving hollow organs. The most common causes are poor blood supply to the anastomosis, tension on the anastomosis, infection, and technical factors. The key to management is recognizing the leak (fever, abdominal pain, peritonitis, signs of sepsis), confirming the diagnosis (clinical assessment, imaging—CT with contrast), and urgent surgical repair (may need to take down anastomosis, create stoma, or re-do anastomosis). Early recognition and prompt treatment are essential—delayed treatment significantly increases mortality.

Key Facts

• Definition: Breakdown or failure of surgical connection between hollow organs
• Incidence: Common (5-15% of bowel anastomoses)
• Mortality: 5-15% overall, higher if delayed treatment
• Peak age: All ages, but more common in older adults
• Critical feature: Fever, abdominal pain, peritonitis, signs of sepsis
• Key investigation: Clinical assessment, CT with contrast
• First-line treatment: Urgent surgical repair

Clinical Pearls

"Fever + abdominal pain after bowel surgery = leak until proven otherwise" — If a patient has fever and abdominal pain after bowel surgery, always think anastomotic leak. Don't miss this.

"CT with contrast is diagnostic" — CT with oral/rectal contrast will show the leak (contrast leaks out). This is the test of choice.

"Time matters" — The longer a leak goes untreated, the higher the mortality. Urgent surgery is essential (usually within 24 hours of recognition).

"May need stoma" — If the leak is severe or the anastomosis can't be repaired, a stoma (bag) may be needed. This is often temporary.

Why This Matters Clinically

Anastomotic leaks are serious post-operative complications with high mortality if not treated promptly. Early recognition (especially fever and abdominal pain after bowel surgery), prompt diagnosis (CT), and urgent surgical repair are essential. This is a condition that surgeons manage frequently, and delayed treatment significantly increases mortality.

Structured Approach: ABCDE

A - Airway

• Assessment: Usually patent
• Action: Secure if compromised

B - Breathing

• Look: May have difficulty breathing (if distension, sepsis)
• Listen: Usually normal
• Measure: SpO2 (may be low if sepsis)
• Action: Support if needed

C - Circulation

• Look: Signs of shock, sepsis
• Feel: Pulse (fast), BP (may be low)
• Listen: Heart sounds (usually normal)
• Measure: BP (may be low), HR (fast)
• Action: IV fluids, may need inotropes

D - Disability

• Assessment: Mental status (may be altered if sepsis)
• Action: Assess if severe

E - Exposure

• Look: Abdominal examination
• Feel: Tenderness, guarding, rigidity
• Action: Complete examination

Specific Examination Findings

Abdominal Examination:

• Inspection: Distension
• Palpation:
  • Tenderness: Severe tenderness
  • Guarding: Muscle guarding
  • Rigidity: Abdominal rigidity
  • Rebound: Rebound tenderness
• Auscultation: Absent or decreased bowel sounds

Signs of Peritonitis:

• Tenderness: Severe
• Guarding: Present
• Rigidity: May have
• Rebound: May have

Special Tests

Natural History (Without Treatment)

Untreated Anastomotic Leak:

• High mortality: 30-50% mortality
• Sepsis: Almost certain
• Poor outcomes: If not treated

Outcomes with Treatment

Factors Affecting Outcomes:

Good Prognosis:

• Early treatment: Better outcomes (within 24 hours)
• Minor leak: Better outcomes
• No sepsis: Better outcomes
• Young, healthy: Better outcomes

Poor Prognosis:

• Delayed treatment: Higher mortality
• Severe leak: Higher mortality
• Sepsis: Higher mortality
• Older, comorbidities: May have worse outcomes

Prognostic Factors

Key Guidelines

1. ERAS Guidelines (2018) — Enhanced recovery after surgery guidelines. ERAS Society

Key Recommendations:

• Early recognition
• Urgent surgery
• Evidence Level: 1A

Landmark Trials

Multiple studies on timing of surgery, outcomes.

Evidence Strength

What is an Anastomotic Leak?

An anastomotic leak is when a surgical connection (anastomosis) between two parts of your bowel breaks down, allowing bowel contents to leak into your abdomen. Think of an anastomosis as two pipes being joined together—when this connection fails, the contents leak out, causing serious infection.

In simple terms: The connection made during your bowel surgery has broken down, and bowel contents are leaking into your abdomen. This is serious and needs urgent treatment, but with prompt surgery, most people recover well.

Why does it matter?

Anastomotic leaks are serious complications with high mortality if not treated promptly. Early recognition and urgent surgical repair are essential. The good news? With prompt treatment, most people recover well.

Think of it like this: It's like a connection breaking—the contents leak out, causing infection. It needs urgent repair, but once fixed, most people recover well.

How is it treated?

1. Diagnosis:

• CT scan: You'll have a CT scan with contrast to see the leak
• Why: To confirm the diagnosis and see how serious it is

2. Resuscitation:

• IV fluids: You'll get fluids through a drip
• Antibiotics: You'll get antibiotics to fight infection
• Why: To support your body while preparing for surgery

3. Urgent Surgery:

• What: The surgeon will operate to fix the leak
• When: Usually within 24 hours
• Why: To stop the leak and prevent serious infection
• What happens: The surgeon will find the leak, repair it or remove the connection, and may need to create a stoma (bag) temporarily or permanently

4. After Surgery:

• Recovery: You'll recover in hospital
• Antibiotics: You'll continue antibiotics
• Stoma: If a stoma was created, you'll learn to care for it

The goal: Fix the leak, treat the infection, and help you recover.

What to expect

Recovery:

• Surgery: Usually within 24 hours
• Hospital stay: Usually weeks (depends on severity)
• Full recovery: Most people recover, but it takes time

After Treatment:

• Stoma: If a stoma was created, you'll need to care for it (may be temporary or permanent)
• Antibiotics: You'll continue antibiotics until the infection is cleared
• Monitoring: Your doctor will monitor to make sure you're recovering
• Follow-up: Regular follow-up to monitor recovery

Recovery Time:

• Simple cases: Usually weeks
• Complex cases: May take months
• If stoma: May need further surgery to reverse stoma

When to seek help

Call 999 (or your emergency number) immediately if:

• You've had bowel surgery and have a high fever and severe abdominal pain
• You've had bowel surgery and feel very unwell
• You've had bowel surgery and your abdomen is very tender
• You feel very unwell

See your doctor if:

• You've had bowel surgery and have symptoms that concern you
• You have concerns about your recovery

Remember: If you've had bowel surgery and have a high fever and severe abdominal pain, especially if your abdomen is very tender, call 999 immediately. Anastomotic leaks are serious, but with prompt treatment, most people recover well. Don't delay—if you're worried, seek help immediately.