You are in: eMedicine Specialties > General Surgery > Abdomen Chyle FistulaArticle Last Updated: Jan 10, 2008AUTHOR AND EDITOR INFORMATIONSection 1 of 12
  Author: Deron J Tessier, MD, Staff Surgeon, Kaiser Permanente Medical Center, Fontana, CA Deron J Tessier is a member of the following medical societies: American College of Surgeons and American Medical Association Coauthor(s): Russell A Williams, MBBS, Program Director, Professor, Department of Surgery, University of California Medical Center at Irvine Editors: Juan B Ochoa, MD, Assistant Professor, Department of Surgery, University of Pittsburgh; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; David L Morris, MD, PhD, Professor, Department of Surgery, St George Hospital, University of New South Wales, Australia; Paolo Zamboni, MD, Professor of Surgery, Chief of Day Surgery Unit, Chair of Vascular Diseases Center, University of Ferrara, Italy; John Geibel, MD, DSc, MA, Professor, Department of Surgery, Section of Gastrointestinal Medicine and Department of Cellular and Molecular Physiology, Yale University School of Medicine; Director of Surgical Research, Department of Surgery, Yale-New Haven Hospital Author and Editor Disclosure Synonyms and related keywords: chyle fistulas, chylous ascites, chylothorax, chyloperitoneum, lymphatic fluid leakage INTRODUCTIONSection 2 of 12
  Chyle fistula is defined as a leakage of lymphatic fluid from the lymphatic vessels, typically accumulating in the thoracic or abdominal cavities, but occasionally manifesting as an external fistula. Chyle fistula is a rare but potentially devastating and morbid condition. First described in the 17th century as complications of trauma, chyle fistulas most commonly occur secondary to lymphatic disease or malignancy or following abdominal, neck, or thoracic operations. Chyle fistulas also can form as a result of venous hypertension, and they have been described in patients with superior vena cava syndrome or thrombosis of the vena cava, among others. History of chyle fistulas
History of the ProcedurePatients with chyle fistulas usually give histories of some comorbid conditions such as malignancy or prior operations in the chest, neck, or abdomen. In postoperative patients, symptoms become evident after the start of oral feeding and depend on the site of obstruction. ProblemChyle fistulas can be extremely morbid due to loss of fluids, electrolytes, and other nutrients. In addition, chyle fistulas can result in loss of lymphocytes and immune dysfunction. Finally, chyle fistulas are space-filling and exert pressure on surrounding tissues, creating symptoms that can range from minimal discomfort to life-threatening situations. FrequencyChyle fistulas are rare events. Typical causes include lymphatic disease; malignancy; trauma; and postoperative trauma following abdominal, neck, or thoracic operations. Postoperatively, approximately 75% of chyloperitoneum cases occur after abdominal aortic aneurysm repair, 19% after aortofemoral bypass, and 7% after resection of infected aortic grafts. EtiologyThe most common causes of chyle fistulas include subclavian vein thrombosis, malignant invasion of the lymphatics, inflammatory reactions (ie, tuberculosis, pancreatitis, cirrhosis, adhesions, pulmonary fibrosis), and prior surgeries near the cisterna chyli or thoracic duct. PathophysiologyLeakage of lymph from damaged lymph vessels is common after surgery or trauma. However, damaged lymphatics most often heal spontaneously or direct lymph centrally via rich interconnected lymphatic collaterals, without any significant morbidity. For chyle fistulas to form, either a scarcity of lymphatic collaterals must be present or the injury to the lymphatic channels must overwhelm the remaining lymphatic vessels. In addition, abnormal lymphatic vessels may be incapable of adequate lymph flow, leading to the accumulation of chyle. Chyle flow varies dramatically depending on the quantity and quality of oral intake. During times of starvation, chyle flow is minimal. After meals, especially those with high contents of long-chain fatty acids, chyle flow increases dramatically. This basic knowledge provides the rationale for controlling dietary intake as part of the treatment of this disease. ClinicalBecause of the relatively low incidence of chyle fistulas, a high index of suspicion is required to make a timely diagnosis. Diagnosis usually is made after the patient has recovered from the injury and has started eating. Symptoms of chyloperitoneum include (1) nausea, (2) vomiting, (3) early satiety or anorexia, (4) abdominal discomfort or pain, and (5) dyspnea due to chylous fluid causing abdominal distention and pressure on the visceral structures and diaphragm. Symptoms of chylothorax include (1) shortness of breath, (2) pleural effusion, and (3) decreased cardiac preload due to a mediastinal shift from a large chylothorax. INDICATIONSSection 3 of 12
Characteristics of thoracentesis or paracentesis aspirate
RELEVANT ANATOMYSection 4 of 12
The cisterna chyli and thoracic duct drain lymph from the entire body except the head, neck, arms, and right thorax (which instead use the right bronchomediastinal, jugular, and subclavian lymph trunks to form the right lymph duct). The anatomy is highly variable, with 50% of people not having an identifiable cisterna chyli. In addition, half of the 4 liters of lymph draining through the cisterna chyli and thoracic duct originates from the intestinal and hepatic lymphatics. The cisterna chyli is found on the posterolateral edge to the right of the aorta at the level of vertebral bodies T12, L1, L2, and L3 as lymphatics from the mesentery, intercostal, and lumbar regions coalesce in the retroperitoneal space. At approximately L1, the cisterna chyle ascends, becoming the thoracic duct. The duct then enters the posterior mediastinum, crosses at T4 into the left retropleural space, and continues in a cephalad direction. The thoracic duct then enters the venous system at the junction of the left subclavian and internal jugular veins (see Media file 1). CONTRAINDICATIONSSection 5 of 12
Contraindications to surgical correction of chyle fistulas are based on the patient's comorbidities and his or her ability to tolerate surgery. TREATMENTSection 6 of 12
Medical therapyTreatment of chyle fistulas is determined by the following:
Nutritional intervention remains the mainstay of nonoperative treatment. Nutritional therapy includes the following:
Several case reports and case series have reported the successful treatment of chylous leaks using octreotide in infants. One series reported 100% closure of chylous leaks from malignancy using 50 mcg of subcutaneous octreotide 3 times per day. Transjugular intrahepatic portosystemic shunts (TIPS) have been reported to successfully treat chylous ascites due to cirrhosis. A period of observation from one to several weeks should be allowed before determining whether these therapies are successful. Repeated paracentesis/thoracentesis should be avoided because (1) results from this treatment modality are poor; (2) the chance of infecting chylous fluid is increased; (3) anasarca and cachexia may occur due to rapid loss of body protein, fat, and fluid; and (4) loss of lymphocytes may result in immune dysfunction. In patients in whom accumulation of chyle leads to significant problems, such as shortness of breath and lung collapse, the use of drainage through a thoracostomy tube or paracentesis may be necessary despite the obvious adverse effects that this form of therapy may produce. Surgical therapySurgery is undertaken when conservative therapies fail (approximately 40%). Surgical therapies include the following:
Preoperative detailsIf at all possible, ensure nutritional assessment and repletion before a surgical intervention because malnutrition increases morbidity significantly. Administer gram-positive antibiotic coverage with a beta-lactamase inhibitor in the 24 hours prior to insertion of the shunt. Because of the possible complication of disseminated intravascular coagulopathy, which is especially prevalent in patients with malignancy, include coagulation parameters in the preoperative evaluation. Intraoperative detailsSurgical approaches vary significantly depending on the site and etiology of the leak. Surgical approach to the thorax using a thoracoscopic approach may be tried, as long as adequate expertise is available. Denver and LeVeen shunts differ in the type of valve each uses.
Postoperative detailsAntibiotic coverage is continued empirically for 4 days after surgery. Any coagulopathy should be treated aggressively without delay. Follow-upPatients should be monitored routinely until the resolution of the fistula. Postoperative visits should commence approximately 1 week after the patient is discharged from the hospital. COMPLICATIONSSection 7 of 12
Untreated, chyle fistulas can be fatal, with patients dying from severe fluid and electrolyte abnormalities, malnutrition, and overwhelming infections, including peritonitis and empyema. Iatrogenic complications also can occur. Complications from shunt placement, including disseminated intravascular coagulopathy, shunt failure, and fluid overload, also can occur. OUTCOME AND PROGNOSISSection 8 of 12
Treatment of chyle fistula is very successful. However, unless the underlying etiology is reversed, the problem can be chronic and unrelenting. FUTURE AND CONTROVERSIESSection 9 of 12
The duration of medical therapies undertaken and the decision to proceed operatively are physician dependent. Because of the relative rarity of chyle fistulas, no definitive data are available to unequivocally direct the duration of therapy. ACKNOWLEDGMENTSSection 10 of 12
The authors and editors of eMedicine gratefully acknowledge the contributions of previous coauthor, Yale D Podnos, MD, MPH, to the development and writing of this article. MULTIMEDIASection 11 of 12
REFERENCESSection 12 of 12
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