Abstract
CASE REPORT
In March 2002, a 75-year-old man was referred to the Otolaryngology—Head and Neck Surgery Department for evaluation of a slowly growing left neck mass. Physical examination revealed a large, indurated mass in the left posterior triangle that was tender and fixed to the underlying tissues. The remainder of the history and physical assessment did not reveal any other abnormalities. A computed tomography (CT) scan with contrast revealed a heterogeneously enhancing left neck mass associated with an irregularly contoured left thyroid. A fine needle aspiration biopsy (FNAB) was obtained from the left neck mass and showed papillary carcinoma.
The patient subsequently underwent a total thyroidectomy and modified radical left neck dissection with sparing of the sternocleidomastoid muscle and spinal accessory nerve. The tumor was adherent to the left internal jugular vein and it was elected to remove the vessel in continuity with the mass. At the completion of the dissection, a small chyle leak was recognized and the thoracic duct was identified, ligated, and oversewn. Valsalva maneuvers repeatedly induced by the anesthetist on multiple occasions demonstrated that the thoracic duct leak was successfully closed. Further inspection before closure of the wound revealed adequate hemostasis and no drainage from the thoracic duct. A 1/2 inch drain was placed.
The immediate postoperative course was unremarkable and by the third hospital day the patient was tolerating a full oral diet. On postoperative day 4, a moderate quantity of milky fluid appeared from the drain site, and 15 mL was sent to Biochemistry and Microbiology for analysis. A new pressure dressing was applied, but the drainage continued to progress. His diet was changed to a zero-fat diet consisting of clear fluids, fruit, and Vital Resource Fruit Beverage. Biochemical analysis revealed a triglyceride level of 9.64 mmol/L in the aspirate. The sample sent to the microbiology laboratory grew coagulase-negative Staphalococcus aureus. The infection was successfully treated with a 10-day course of cloxacillin. During the next 15 days, the patient continued to have soaking through his pressure dressings despite daily changes. On hospital day 18, subcutaneous Octreotide 100 μg three times daily was started to decrease the chyle output before starting the patient on total parenternal nutrition (TPN). Within 24 hours, the chyle fistula stopped draining completely. After several days without drainage, the patient was started on a full oral diet with no recurrence of the chyle leak. He received a total of 8 days of Octreotide treatment before being discharged home in good condition.
DISCUSSION
Chyle fistula resulting from violation of the thoracic duct or right lymphatic duct during neck dissection is a rare complication with potentially serious morbidity. It is reported to occur in 1% to 2.5% of neck dissections, 1 but it has also been documented after penetrating neck trauma, cervical node biopsy, and cervical rib resection. 2 Chyle fistulas are significant in that they can impair nutrition, cause metabolic disturbances, compromise and delay wound healing, result in skin flap necrosis, prolong hospitalization, and produce chylothorax. Medical management is the first line of treatment and aims to diminish chyle flow. These measures include allowing adequate drainage, applying pressure dressings, serial aspirations, bed rest, and nutritional modifications. 2 Nutrition can be provided enterally with an elemental diet supplemented with medium-chain triglycerides (MCTs) that are absorbed directly into the portal circulation, bypassing the lymphatic system. TPN is an alternative dietary modification to the use of MCTs; however, the need for a central venous line and the increased cost make TPN a second-line approach at most institutions. The indication for surgical intervention is controversial, but persistent output of more than 600 mL/day for several days despite medical therapy or extremely high output (>2 L) is an appropriate indication.
Octreotide, a long-acting synthetic analogue of somatostatin, is a promising addition to the conservative medical management of chyle fistulas. Somatostain is a peptide that acts both as a neurohormone and paracrine agent. Its biologic actions are extremely diverse and include the inhibition of thyroid-stimulating hormone, growth hormone, vasoactive intestinal peptide, gastrin, motillin, insulin, glucagon, intestinal secretions, and bile flow. 3 Somatostain's effectiveness in the context of chyle fistulas may be due to its ability to reduce gastrointestinal and pancreatic secretions, decrease hepatic venous pressure, and reduce splanchnic blood flow. 3 It has been demonstrated to decrease the thoracic duct lymph flow rate and the ratio of triglycerides in the lymph to that in serum in dogs. 4 Among its other pharmacologic uses, Octreotide is effective in neuroendocrine tumor hyperfunction, pituitary tumors, pancreatic fistulas, and high output enterostomies. The major documented complication of long-term Octreotide treatment is the increased incidence of gallstones secondary to decreased bile production and gallbladder contractility. The less dramatic side effects include abdominal discomfort and decreased fat absorption.
To our knowledge, there is only one other case report noting the use of Octreotide in the event of chyle fistula to the neck originating from the thoracic duct. 5 However, other case reports have documented its efficacy in treatment of chylothorax. 6 For all of these patients, there was a marked decrease in chyle production within 24 hours of starting therapy and no observed side effects. This permitted the resumption of a regular oral diet within days of instituting Octreotide treatment. The rapid response and minimal side effect profile make Octreotide an attractive addition to the medical management of a chyle fistula. Earlier institution of Octreotide therapy may reduce expenses incurred and patient morbidity. Obviously, further studies need to validate this observation and surgical intervention may still be required if persistent drainage continues to be high.