131: Percutaneous Therapy for Traumatic Chylothorax

Introduction

Iatrogenic disruption of the thoracic duct is an uncommon but potentially serious complication of thoracic surgery, particularly esophagectomy.¹ The thoracic duct conveys chyle and lymph from the liver, intestines, abdominal wall, and lower extremities into the systemic venous circulation, and depending on diet and activity, the flow of chyle through the thoracic duct can reach several liters per day.² Among other components, this fluid contains essential proteins, lipids, and lymphocytes. The clinical sequelae of unremitting chylous effusions can be severe and life-threatening, including immunosuppression, respiratory compromise, dehydration, cachexia, and death.

Conservative management of chylous pleural effusions includes chest tube drainage, cessation of oral intake, and institution of total parenteral nutrition to decrease the physiologic production of chyle. If lymph production can be minimized, low-output leaks of less than 500 mL per day can sometimes heal spontaneously, although this process may take several weeks, during which time the patient may become nutritionally and immunologically depleted. As a result, some have called for earlier diagnosis and intervention to avoid metabolic compromise.^3,4 Repeat thoracotomy and direct thoracic duct ligation typically are performed early to stop high-output leaks; however, the morbidity and mortality of reoperation in this patient population is a serious consideration, with complication rates approaching 40%.⁵

Recently, percutaneous thoracic duct embolization (TDE) has been introduced as a minimally invasive technique for controlling high-output chylothorax (Fig. 131-1).⁶ In this chapter, we review the indications, preprocedural assessment, and techniques of percutaneous TDE.

General Principles

The method of TDE for the control of chylothorax requires a comprehensive understanding of the anatomy of the lymphatic system, especially of the thoracic duct and cisterna chyli and their many anatomical variations. TDE is a two-stage procedure, beginning with pedal lymphangiography which is used to visualize the cisterna chyli or dominant upper lumbar lymphatics for possible cannulation. Alternatively, pelvic intranodal lymphangiography can be employed. Once a suitable retroperitoneal target has been identified, the thoracic duct is accessed percutaneously and embolized, typically from a right anterior oblique transabdominal approach to avoid the aorta, or a right posterior oblique transhepatic approach. If the thoracic duct cannot be cannulated, maceration of the cisterna chyli and upper lumbar lymphatics is undertaken to divert the flow of chyle into the retroperitoneum. One variation of TDE entails retrograde cannulation of the thoracic duct via its ostium near the left angulus venosus, using a coaxial catheter system delivered from a left brachial or basilic vein approach. The retrograde transvenous approach is less reliable, however, owing to the difficulties encountered in locating and seating a catheter in the ostium of the thoracic duct under fluoroscopy and the ...