A 70-year-old man developed a pleural effusion 3 days following esophagectomy. Thoracentesis demonstrates cloudy fluid with a triglyceride concentration of 800 mg per deciliter. Each of the following is a management option EXCEPT

A. ligation of the thoracic duct at its junction with the jugular vein
B. talc poudrage
C. thoracotomy and direct closure of the injured thoracic duct
D. thoracotomy with ligation of the thoracic duct
E. total parenteral nutrition

Answer A

Postoperative chylothorax is an uncommon complication following esophagectomy, occurring in only 2.4% of patients undergoing transhiatal esophagectomy. The diagnosis of chylothorax should be suspected when aspiration of a pleural effusion yields cloudy fluid or when there is excessive chest tube drainage of a cloudy or non-bloody nature. The triglyceride concentration of the fluid can be measured. Pleural fluid with a triglyceride concentration of less than 50 mg/dl has a 5% chance of being chylous, whereas fluid with a triglyceride concentration of over 110 mg/dl has a 99% chance of being chylous. 

Loss of fluid, protein, and lymphocytes can result in electrolyte abnormalities and altered immune function. Chylothorax following esophagectomy is a serious problem in this patient population that is marked by suboptimal nutrition. Intravenous alimentation may be reasonable for a few days, but a surgical approach is warranted if the fluid drainage does not quickly decrease to a rate below 200-400 cc per 8-hour shift. 

The operative approach is related to both thoracic duct anatomy and the side of the chylothorax. The thoracic duct traverses the diaphragm through the aortic hiatus, posterior to the esophagus, between the aorta and the azygous vein. Although thoracic duct anatomy is variable, it commonly crosses from the right to the left near the levels of the T4 or T5 vertebral bodies. It then ascends posterior to the aortic arch, enters the neck posterior to the carotid sheath, and empties into the junction of the left internal jugular and subclavian veins. Injury to the thoracic duct may be avoided by maintaining dissection close to the esophageal wall and by ligating, rather than cauterizing, periesophageal tissues. 

Optimal surgical management of the complication consists of direct repair of the injured duct via thoracotomy (or thoracoscopy) on the affected side. Administration of cream, by mouth, nasogastric tube, or jejunostomy tube, frequently demonstrates the site of injury, thereby allowing direct repair. If the site of injury cannot be visualized, the duct can be ligated at the level of the diaphragm either through the left or right thoracic cavities. Ligation of the duct in the neck will not prevent continued accumulation of chyle in the pleural cavity. Talc poudrage may be an effective alternative in some patients. 

Orringer MB, Bluett M, Deeb GM. Aggressive treatment of chylothorax complicating transhiatal esophagectomy without thoracotomy. Surgery 1988;104:720-6.
Chylothorax is an unusual complication after transhiatal esophagectomy (THE) and in the past 10 years has occurred in 11 of 320 patients (3%) undergoing this operation for diseases of the intrathoracic esophagus. Four patients had benign esophageal disease: scleroderma reflux esophagitis (1), caustic stricture (1), and achalasia (2), and each had undergone at least one previous esophageal operation. Seven patients had intrathoracic esophageal carcinoma--two upper-third, two middle-third, and three distal-third lesions. Excessive chest tube drainage more than 72 hours after THE was the standard presentation, and the diagnosis of chylothorax was confirmed by the administration of cream through the jejunostomy feeding tube placed routinely at operation. The character of the chest tube drainage changed from serous to opalescent. Aggressive treatment of this complication was the rule, and every patient underwent a thoracotomy between 2 to 14 day (average, 6 days) after the diagnosis was established. Cream was administered through the jejunostomy tube before operation, and in each case the thoracic duct injury was readily identified and controlled with suture ligatures. There were no deaths in this group, and there was one recurrence of the fistula that required re-operation; all patients were discharged from the hospital within 3 to 29 days (average, 10 days) after thoracic duct ligation. It is concluded that early recognition of a chylothorax after transhiatal esophagectomy with prompt transthoracic ligation of the injured duct results in a shorter overall hospitalization and lower morbidity and mortality from this complication. The traditional conservative management of chylothorax with intravenous hyperalimentation and no or low-residue enteral feedings has little place in this nutritionally depleted patient population.

Patterson GA, Todd TRJ, Delarue NC, et al. Supradiaphragmatic ligation of the thoracic duct in intractable chylous fistula. Ann Thorac Surg 1981;32:44-9.
Spontaneous closure of a chylous fistula is usual, but the rare intractable fistula may lead to disastrous nutritional and immunological consequences. We report the surgical management of 5 patients with intractable fistulas with daily drainage averaging 2,060 ml. Conservative therapy failing, the 5 patients underwent 6 ligations of the thoracic duct. A limited posterolateral thoracotomy was used in 3, full right thoracotomy in 2, and left thoracotomy in 1. Ligations were carried out immediately above the diaphragm, and not at the fistula site, by a mass ligature technique encircling all tissue between the azygos vein and aorta. The ligation achieved immediate cessation of drainage in four of five initial procedures and in the fifth patient, at a second operation. High-output thoracic duct fistulas may be handled by supradiaphragmatic ligation of the thoracic duct. Identification of the fistula site or the dissection of the thoracic duct itself is avoided by this technique.

Staats BA, Ellefson RD, Budhan LL, et al. The lipoprotein profile of chylous and nonchylous pleural effusions. Mayo Clin Proc 1980;55:700-4.
The lipoprotein electrophoregrams and the cholesterol and triglyceride levels of the pleural fluid were evaluated for patients with chylous pleural effusions, as defined by the presence of a distinctive band of chylomicrons on the lipoprotein electrophoregram, and in patients with nonchylous effusions of various causes. One hundred forty-one patients were studied during a 3-year period. The chylous effusions had strikingly higher triglyceride levels (median 249, range 49 to 2,270 mg/dl) than the nonchylous group (median 33, range 13 to 107 mg/dl); there were no significant differences in cholesterol or protein between the two groups. The gross description of the fluid was a poor indicator of its origin, being described as consistent with chyle in less than 50% of cases of chylous effusions. The triglyceride values distinguished chylous effusion from nonchylous effusion; values greater than 110 mg/dl are highly suggestive of a chylous effusion. Equivocal cases--triglyceride values between 50 and 110 mg/dl--required lipoprotein analysis. Pleural effusions of undetermined cause, regardless of gross appearance of the fluid, require that a screening triglyceride value be obtained to rule out a chylous effusion.