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Chylothorax
Medical expert of the article
Last reviewed: 07.07.2025
Chylothorax is an accumulation of lymphatic fluid in the chest cavity. It is a serious and often life-threatening condition, often causing cardiopulmonary failure, metabolic, electrolyte and immunological disturbances.
Classification of chylothorax:
- congenital chylothorax;
- traumatic chylothorax;
- non-traumatic chylothorax.
Chylous pleural effusion in newborns may appear spontaneously, with congenital anomalies of the thoracic duct or birth trauma. The causes of congenital chylothorax may be anomalies in the development of the duct: anomalies in the connection of the duct branches during embryogenesis, congenital duct fistulas, congenital intraductal obstruction.
Traumatic chylothorax may occur after trauma and surgical interventions on the chest organs: heart surgery, aorta, esophagus, lungs, sympathetic system structures. Damage to the thoracic duct during surgery is to some extent facilitated by its abnormal course, which is observed in more than 50% of patients. Damage to the duct in the neck may occur during lymph node biopsy and novocaine blockades.
Non-traumatic chylothorax may be caused by tumors. In particular, lymphomas and neuroblastomas sometimes lead to obstruction of the thoracic duct, and in lymphangiomatosis, chylous effusion sometimes appears in both the pleural and abdominal cavities. Non-traumatic chylothorax may also develop with thrombosis of the superior vena cava and subclavian veins, aortic aneurysm, filariasis, right ventricular failure, etc.
[ How does chylothorax manifest itself?
Manifesting symptoms may include acute respiratory failure, primarily tachypnea and cyanosis. Physical examination reveals symptoms of fluid accumulation in the pleural cavity - some bulging of the chest wall on the affected side, shortening of the percussion sound and weakening of breathing, shift of the cardiac impulse to the opposite side. Sequestration of lymphatic fluid in the pleural cavities may lead to metabolic disorders: hypoproteinemia, metabolic acidosis, water, electrolyte and immune disorders. Sometimes, with traumatic chylothorax, several weeks pass from the moment of damage to the duct to the manifestation of symptoms. This is due to the development of chyloma under the mediastinal pleura, which subsequently breaks through the pleural cavity.
How to recognize chylothorax?
In this case, effusion is detected in the pleural cavities, determined by chest X-ray or ultrasound. Voluminous chylothorax, diagnosed antenatally by ultrasound. can cause severe respiratory distress syndrome immediately after birth and, accordingly, require emergency pleural puncture. When aspirating effusion in newborns, a clear straw-yellow liquid is usually obtained (if the child has not been fed). The effusion becomes milky in color in children who have previously been fed. Analysis of the effusion usually reveals an increased content of lipids (more than 4-6 g / l) and protein (above 30 g / l - its content in plasma), the triglyceride level exceeds 13 mmol / l. Microscopy shows a predominance of lymphocytes up to 80-90%. These data confirm that the effusion obtained during the puncture is lymph. An increase in body temperature is not typical.
Chylopericardium may also infiltrate the mediastinum and accumulate in the pericardial cavity (chylopericardium). In this case, a symptom of mediastinal expansion or cardiac shadow expansion appears on the chest X-ray. With increasing chylopericardium, hemodynamic signs may develop - compression of the heart (tamponades) - heart failure. Pericardial puncture allows an accurate diagnosis to be made.
A combination of chylothorax and chyloperitoneum is also possible. These conditions may alternate during the treatment period.
How is chylothorax treated?
Treatment of children with chylothorax should begin with total parenteral nutrition and pleural punctures (pericardial punctures in the case of chylopericardium). If repeated pleural punctures are ineffective, drainage of the pleural cavity must be performed. Transferring the child to total parenteral nutrition actually leads to the cessation of lymph formation, which can facilitate recovery. An alternative to transferring the child to total parenteral nutrition is the administration of special mixtures in the form of short- and medium-chain triglycerides (MCTs).
Congenital chylothorax in neonates is usually treatable with pleural punctures or chest drainage. Nontraumatic chylothorax in older children is a reason to exclude intercurrent diseases or malignancies. In traumatic chylothorax, conservative treatment is also usually effective.
Long-standing chylothorax leads to the formation of clots, adhesions and restrictions in the pleural cavity, making it difficult to remove these contents.
If there is no positive dynamics for more than 14 days or if severe metabolic disorders develop, surgical intervention is indicated. The operation of choice is ligation of the thoracic duct at the site of the defect or above the diaphragm. The operation is effective in 96% of cases. A good alternative to standard surgery from a thoracotomy approach is thoracoscopic ligation or clipping of the thoracic duct. To improve visualization of the duct, preoperative administration of fatty foods through a tube is used: cream, sour cream, butter or olive oil. In cases where it is not possible to visualize the thoracic duct, the muscle masses and tissue between the aorta and the azygos vein above the diaphragm are sutured. In severe cases, temporary pleuroperitoneal shunting can be performed.