Review
Chylothorax

https://doi.org/10.1016/S0300-2977(99)00114-XGet rights and content

Abstract

Chylothorax is defined as an accumulation of chyle in the pleural space caused by disruption of the thoracic duct or one of its major divisions. Chyle has a high content of triglycerides. The odourless fluid is turbid and milky due to the presence of fat containing particles, the chylomicrons. The etiology of chylothorax can be divided into four major categories: tumor, trauma, idiopathic and miscellaneous. Although chylothorax is uncommon, it is a serious and potentially hazardous disorder. Loss of chyle leads to metabolic disturbances, malnutrition and immunodeficiency. Treatment consists of treatment of the underlying disease, conservative treatment (medium chain triglyceride diet, parenteral nutrition) or surgical intervention. Appropriate timing of surgical intervention is essential. Since the ligation of the thoracic duct can be performed during thoracoscopy, this minimal interventional technique is the procedure of choice when conservative treatment fails.

Introduction

Chylothorax is defined as an accumulation of chyle in the pleural space caused by disruption of the thoracic duct or one of its major divisions. Although rare, physicians should be aware of the possibility that pleural effusion can be caused by chyle.

Loss of chyle results in the loss of large amounts of fluid, electrolytes, protein, fat, fat-soluble vitamines and lymfocytes, predominantly the T-cell variety. In addition respiration and circulation will be impaired by fluid accumulation. Eventually chylothorax can lead to a life threatening state of malnutrition.

This report deals with anatomy, physiology, diagnosis, etiology, and management of chylothorax.

Three patients with different causes of chylothorax were recently seen in our hospital. They were treated in three different ways. The patient characteristics are summarized in Table 1.

Section snippets

Anatomy

The thoracic duct is formed by the lymph vessels from the peritoneal cavity and the lower parts of the body. At its origin it usually extends from a dilatation, the cisterna chyli, which lies just anterior to the first or second lumbar vertebra. Through the aortic hiatus the duct passes the diaphragm, continues upwards into the posterior mediastinum on the right side of the vertrebral column between the aorta and the azygos vein. It crosses the midline to the left between the sixth and fourth

Physiology

Chyle contains lymph, mainly from intestinal origin. It has a high content of triglycerides. The odourless fluid is turbid and milky due to the presence of spherical triglyceride containig particles, the chylomicrons.

However, not every milky pleural effusion is chyle. Exsudates that have been present in the pleural space for a long time, have the tendency to become enriched with cholesterol, especially when the pleura is fibrotic. A high content of cholesterol may also yield a thick, opalescent

Differentiation on gross appearance

In a retrospective study, the milky (‘chylous’) appearance was only found in 18 of 38 patients (47%). Chyle appeared as a bloody effusion in 26%, and was yellow turbid in 10%. Chylous effusions are hardly ever serous or serosanguinous. After starvation, the milky appearance may disappear. A chylous effusion becomes milky again 3 h after oral intake of a few spoons of cream.

Chyle can easily be differentiated from pseudochyle and empyema. After centrifugation, empyema leaves a clear supernatant

Etiology and management

Chylothorax usually is the result of leakage of the thoracic duct. This is due to rupture, extrinsic compression or obliteration of the duct. In case of compression or obliteration chylous effusion will develop after the congestion of the numerous collaterals and lymphatic-venous anastomoses by lymph.

Before it enters the pleural space, first a collection of chyle below the pleura, a chyloma, is formed. Later the pleura bursts and the chyle flows into the pleural space. A chyloma is rarely seen

Summary

Chylothorax is a rare but serious disorder that can have severe repiratory and metabolic consequences. The anatomy of the lymphatic system has many variations and, as demonstrated in our three cases, the etiology of chylous effusion is diverse. Drainage and dietary modification can be a successful treatment of chylothorax, but prolonged conservative therapy can result in malnutrition, metabolic disturbances and immunodeficiency. Appropriate timing of surgical intervention is essential. Since

References (45)

  • D. Graham et al.

    Use of video-assisted thoracic surgery in the treatment of chylothorax

    Ann Thorac Surg

    (1994)
  • R.J. Cerfolio et al.

    Deschamps C. et al. Postoperative chylothorax

    J Thorac Cardiovasc Surg

    (1996)
  • R.G. Inderbitzi et al.

    Treatment of postoperative chylothorax by fibrin glue application under thoracoscopic view with use of local anesthesia

    J Thorac Cardiovasc Surg

    (1992)
  • E. Akaogi et al.

    Treatment of postoperative chylothorax with intrapleural fibrin glue

    Ann Thorac Surg

    (1989)
  • S.P. Cummings et al.

    Successful treatment of postoperative chylothorax using an external pleuroperitoneal shunt

    Ann Thorac Surg

    (1992)
  • J.P. Janssen et al.

    Thoracoscopic treatment of postoperative chylothorax after coronary bypass surgery

    Thorax

    (1994)
  • E.G. Restoy et al.

    Spontaneous bilateral chylothorax: uniform features of a rare condition

    Eur Resp J

    (1988)
  • G. Hillerdal

    Chylothorax and pseudochylothorax

    Eur Respir J

    (1997)
  • J. MacFarlane et al.

    Chylothorax

    Am Rev Respir Dis

    (1972)
  • I. Yeam et al.

    Hemothorax and chylothorax

    Curr Opin Pulmon Med

    (1997)
  • B.A. Staats et al.

    The lipoprotein profile of chylous and nonchylous pleural effusions

    Mayo Clin Proc

    (1980)
  • Cited by (0)

    View full text