What is the diagnosis and treatment for a chyle leak (chylothorax)?

From the Guidelines

For patients with a chyle leak, conservative management should be attempted first, but if this approach fails, thoracic duct embolization (TDE) is a viable and effective treatment option, with clinical success rates ranging from 64% to 90% 1. The management of a chyle leak depends on the severity and location of the leak, as well as the underlying etiology. Conservative measures, such as dietary modifications, total parenteral nutrition, and adjunctive therapy with somatostatin or octreotide, can be effective in managing small to moderate leaks 1. However, for larger leaks or those that persist despite conservative management, more invasive treatments may be necessary. Some key considerations for the management of chyle leaks include:

• The use of total parenteral nutrition to reduce intestinal lymph flow and allow the leak to heal
• The administration of octreotide to reduce lymphatic flow
• The consideration of TDE as a viable treatment option for patients who have failed conservative management, with clinical success rates ranging from 64% to 90% 1
• The potential risks and complications associated with TDE, including acute complications such as leg swelling, abdominal swelling, or chronic diarrhea, which may be seen in up to 14% of patients 1 It is essential to note that the evidence for the management of chyle leaks is largely based on case series and expert opinion, and therefore, the treatment approach should be individualized to each patient's specific needs and circumstances 1.

From the Research

Definition and Causes of Chyle Leak

• Chyle leaks occur when there is interruption to the lymphatic ducts that transport chyle around the body 2
• The loss of this protein-rich, calorie-rich fluid can cause serious complications including dehydration, malnutrition, and immunosuppression 2
• Chyle leaks can be caused by surgical procedures, malignant invasion, or medical conditions 2

Management of Chyle Leaks

• Nutritional support is vital and leads to spontaneous leak closure in many cases 2
• Management options include total bowel rest with parenteral nutrition, enteral feeding with specialized formula, or oral diet with supplementation 2
• Conservative management with non-suction drainage, low-fat diet, and axillary compression bandaging appear effective where output <500ml/24 hrs 3
• Secondary surgical management should be considered in high chylous output (<500mls/24 hrs) patients unresponsive to conservative measures 3

Treatment Strategies

• Etilefrine, a sympathomimetic drug, can be used to induce contraction of the smooth muscle fibres present in the wall of the main thoracic chyle ducts, reducing chyle flow output 4
• A proposed classification system based on the drainage volume of chyle leak can provide a practical and tailored guide to management 5
• Nutritional support involves coordinated care between healthcare providers to provide a combination of various modalities, including nil by mouth, parenteral nutrition, enteral feeding with formula modifications, and oral diet 6

Incidence and Risk Factors

• Chyle leaks following surgery to the axilla are seldom encountered with an incidence <0.7% 3
• Aberrant thoracic duct anatomy represents the likeliest aetiology of chyle leaks after axillary surgery 3
• Chyle leak or chylous ascites remains a rare complication after laparoscopic living-donor nephrectomy, with an incidence of 2.25% in one study 5