Anastomotic Leak Guidelines

Prevention
Diagnosis
Grading of anastomotic leaks
Management of anastomotic leaks
Managing the patient and their family
Managing the surgeon

Anastomotic leaks are the leading cause of major morbidity and mortality in gastrointestinal surgery. Prevention, early identification and correct management are fundamental to improve outcomes.

Prevention

• The anastomosis must be tension free
• The bowel must be healthy with adequate pulsatile blood supply
• There must be no distal obstruction
• The patient must be able to heal

The following increase the risk of anastomotic leakage, and should prompt consideration of proximal diversion:

• >10% weight loss in the preceding 3 months
• Recent use of corticosteroids
• Radiation of bowel
• Advanced chronic illness
• Metastatic cancer
• Septic shock

Diagnosis

Early anastomotic breakdown (< 4 days)

• This is uncommon, and is the result of a technical problem in the creation of the anastomosis.
• It will present with an acute deterioration of the patient’s physiological parameters.
• The diagnosis is made predominantly on clinical grounds.
• Relook laparotomy/laparoscopy is the correct diagnostic and therapeutic intervention.
• Blood tests can be used to corroborate the presence of sepsis, but are not diagnostic.
• CT scan has a limited role, and undue delay to obtain a CT scan in a patient with overt clinical deterioration in the early post operative period will result in adverse outcomes.

Late anastomotic leaks (> 5 days)

• Signs of sepsis, patient stable, no other sites of infection: request CT scan, and/or percutaneous drain.
• It is important to note that patients with an intra abdominal abscess will often only have a low grade temperature niggle as low as only 37.5. This classically occurs on day 5.
• Be wary of diagnosing “pneumonia” or “UTI” at this time, in a patient who has undergone an anastomosis.

Using CRP levels:

• On day 4 postoperatively all patients with an anastomosis at an elective operation should have a CRP performed.
• CRP < 130 on day 4 is highly suggestive of a good outcome and is essential if one is considering an early discharge.
•  CRP > 130 is suspicious, but not synonymous of an anastomotic leak. If a patient has no other causes of sepsis and no other features suggestive of infection i.e a raised WCC, pulse rate or temperature then a repeat CRP the next day may be appropriate.
• Rising CRP (with no other obvious clinical source of infection)= a CT scan is essential to rule out an anastomotic leak.

Interpreting the results of CT

• A CT scan is the best special investigation for identifying an anastomotic leak
• If the patient has a left sided colonic anastomosis the CT should include rectal contrast as well as IV and oral contrast.
• A CT scan is performed to diagnose an intra abdominal abscess and facilitate percutaneous drainage, or to guide re look surgery.

Findings suggestive of an anastomotic leak include:

• Intra peritoneal air >5 days post op
• Free fluid
• Intra-abdominal abscess
• Extravasation of contrast

Equivocal findings

• Inflammatory stranding is a common post surgical finding and on its own is not indicative of an anastomotic leak.
• A “negative” scan is reassuring, but not exclude a leak unequivocally. Use your clinical judgement in this context.

The presence of free air or a contrast leak does not mandate the performance of a laparotomy. 

The decision to perform a laparotomy is not determined by the confirmation of a leak on CT scan but rather by the patient’s clinical condition. 

Grading of anastomotic leaks

All leaks should be graded.

Management of anastomotic leaks

All patients must receive IV broad spectrum antibiotics, even if they appear clinically well. In the antibiotic naive patient Augmentin 1.2 grams IV is an appropriate first line choice.

Relook laparotomy/laparoscopy is the correct diagnostic and therapeutic intervention for an early anastomotic leak.

The primary treatment of a late anastomotic leak is radiological drainage of the associated abscess.

• Collections smaller than 5 cm can be managed with antibiotics alone, if they are inaccessible to radiological drainage.
• Aspiration alone is an alternative if the collection cannot be safely drained
• Collections larger than 5 cm need percutaneous drainage.
• Open drainage via laparotomy is discouraged in most situations, and must be performed under the supervision of a senior member of the operative team. This is not something to be delegated to the junior medical officer on call at night.

If the anastomotic leak is diagnosed at a relook laparotomy, the patient will require a proximal diverting stoma in almost all situations.

• It is extremely uncommon to be able to successfully repair a leaking anastomosis at a relook laparotomy.
• If anastomotic salvage is to be attempted this should be in consultation with the Colorectal Surgery Unit at Groote Schuur Hospital.
• If a stoma is to be constructed an attempt should be made to bring out a double barrelled stoma if the clinical situation allows.
• If it is technically impossible to fashion a proximal stoma, the surgical goal must be to create a controlled fistula by draining the area adequately, and to limit further intraperitoneal contamination.
• Consider establishing routes of distal enteral access for feeding purposes (feeding jejunostomy).
• An attempt should be made to close the abdomen if respiratory pressures and abdominal wall tension allow it.

Late laparotomy (>2 weeks post op) should be avoided in almost all cases.

• It is extremely unusual to require a laparotomy from 2-6 weeks after index surgery.
• The chance of encountering dense adhesions and causing multiple enterotomies is extremely high, so that unless ischaemic bowel is suspected a laparotomy should be avoided.
• Extra-peritoneal routes of open access can be considered in selected cases.
• cases where this is considered should be discussed with the Colorectal Surgery Unit.

Managing the patient and their family

An anastomotic leak results in major morbidity, prolonged hospital stay, and mortality.

The possibility and implications of an anastomotic leak must always be discussed when obtaining preoperative consent.

Clinical records must be thorough, and updated regularly.

It is essential to communicate frankly and frequently with the patient and their family. This must be documented in the clinical records.

Managing the surgeon

It is common for the surgeon who performed the index operation to experience an extreme sense of guilt and despair in this context, so that his/her clinical judgement is impaired.

It is wise to seek counsel and support of a senior colleague.

A patient with an anastomotic leak is best managed in a multidisciplinary context.

The relook laparotomy and long term care of a patient with an anastomotic leak are best managed by a surgeon who was not involved in the index procedure.