Hepatic Hydrothorax - Causes, Diagnosis, and Treatment

Introduction:

Hepatic hydrothorax occurs in patients with cirrhosis, a chronic liver disease. It occurs due to fluid build-up in the pleural space. The condition is found by analyzing the fluid extracted from the chest cavity and a few imaging techniques. Symptoms like cough, shortness of breath, tiredness, and chest pain occur in hepatic hydrothorax patients. Hepatic hydrothorax is treated with medications, transjugular intrahepatic portosystemic shunt (TIPS), and liver transplantation.

What Is Hepatic Hydrothorax?

It is the water (hydro) or fluid build-up in the pleural space due to liver (hepatic) disease. It is called pleural effusion. It occurs in patients with cirrhosis (scarring of healthy liver tissues). The fluid from the ascites moves directly into the pleural cavity. Patients with cirrhosis have ascites (fluid accumulation in the belly) due to increased pressure in the blood vessels that supply the liver. The scar tissue blocks the blood circulation in the liver and affects the kidney functions over time, and excess salt is not removed from the body. The salts hold extra fluids and eventually lead to fluid accumulation.

Pleura is thin, double-layered tissue that lines the lungs and the inside of the chest cavity. Pleural space is the gap between the pleura. When there is fluid stocked up in the pleural space, it is called pleural effusion. The pleural effusion is of two types: transudate and exudate. Transudate effusion occurs when a pressure imbalance occurs in the blood vessels leading to leakage into the pleural cavity. It is seen in patients with cirrhosis and heart diseases. Exudate effusion occurs when the pleura is injured or swollen. It is seen in patients with pneumonia (lungs air sacs become swollen due to infection), cancer, and kidney diseases.

What Causes Hepatic Hydrothorax?

The exact causes of hepatic hydrothorax are unclear. The fluid from the ascites in the abdominal cavity moves into the pleural space through the diaphragm. A few damages to the tissues in the diaphragm make way for fluid entry. The pleural effusion becomes more prominent when the pleural space's storage capacity is exceeded.

Portal hypertension (high pressure in the blood vessels that supply the liver) causes ascites, leading to pleural effusion. Portal hypertension is common in cirrhosis patients, as the scar tissue blocks or constricts the size of the blood vessel. It causes pressure build-up in the blood vessel, and it ruptures. The fluids escape into the neighboring structures leading to excess fluid storage in the belly.

What Are the Symptoms of Hepatic Hydrothorax?

Hepatic hydrothorax has no specific symptoms as it generally occurs along with ascites. If the pleural effusion is massive, then the following symptoms may appear:

• Feeling short of breath.

• Cough.

• Respiratory failure (the blood has increased carbon dioxide and reduced oxygen).

• Chest pain.

• Feeling weak and tired.

What Are the Tests to Find Hepatic Hydrothorax?

• Physical Examination: The doctor looks at the patient for any signs of swelling in the abdomen.

• Analyzing Pleural Fluid: A puncture is made in the chest cavity to access the pleural space and extract the fluid for evaluation. It will help confirm if the effusion is a transudate or exudate type.

• Radioisotope Scintigraphy: A radiotracer 99 m Tc sulfur colloid is injected to look for the tracer's pathway. It is a confirmatory test for hepatic hydrothorax. The result is positive for hepatic hydrothorax if the tracer travels from the peritoneal space to the pleural space.

• Doppler Ultrasonography: High-frequency bouncing sound waves are used to capture images of the blood vessels. It shows the flow of fluid in the hepatic hydrothorax through the diaphragm.

• Magnetic Resonance Imaging (MRI): Magnetic resonance imaging techniques use high-frequency sound waves in a magnetic field to capture images of internal organs and structures. It gives a detailed view of the tissues and organs.

How Is Hepatic Hydrothorax Treated?

• Salt Restriction: A low-sodium (salt) diet is recommended for patients with hepatic hydrothorax.

• Diuretics: Diuretics is a medicine used to reduce blood pressure in patients with elevated blood pressure. The drug acts by removing the excess salt and water in the body.

• Thoracentesis: It is a procedure that is used to remove air or water from the lungs. A needle is inserted in the chest to access the pleural space. The trapped fluid in the pleural cavity is removed.

• Transjugular Intrahepatic Portosystemic Shunt (TIPS): Transjugular intrahepatic portosystemic shunt creates an artificial passage between the portal vein (a blood vessel that supplies blood to the liver) and hepatic vein (a blood vessel that carries blood from the liver to the heart). A stent (a tiny metal tube) is placed between the blood vessels to establish communication between the hepatic and portal veins.

• Liver Transplantation: Liver transplant is considered in severe cirrhosis and when other treatment methods are not beneficial. A whole liver or a part of a liver from a healthy donor is surgically implanted in the patient.

What Are the Complications of Hepatic Hydrothorax?

• Acute Kidney Injury: It is the sudden failure of kidney functions due to excess build-up of toxins in the kidney. It happens within a few hours or a few days.

• Hepatic Encephalopathy: It is a brain disorder due to liver damage when the liver does not remove toxins from the blood. These toxins reach the brain through circulation and damage the brain cells. It causes forgetfulness, disorientation, slurred speech, trembling hands, and confusion.

• Risk of Mortality: There is an increased risk of mortality in patients with hepatic hydrothorax. Since the functions of most organs are compromised and lead to failure, the patient's death occurs in some cases.

What Is the Prognosis of Hepatic Hydrothorax?

The prognosis is poor in patients with hepatic hydrothorax. It occurs in patients with ascites and cirrhosis, and liver transplant and transjugular intrahepatic portosystemic shunt are the treatment of choice. However, most patients are not eligible for liver transplants, and there is an increased fatality risk.

Conclusion:

Hepatic hydrothorax is a rare type of pleural effusion that occurs only in patients with cirrhosis, and the effusion is above 500 ml (milliliter). Pleural effusion also occurs in patients with heart problems and lung diseases. But hepatic hydrothorax is different as it results due to cirrhosis, a chronic liver disease. In hepatic hydrothorax, the pleural effusion is on the right side only. The condition is found with a few imaging techniques and by analyzing the fluid in the pleural space. However, there are a few treatments, like thoracentesis and transjugular portosystemic shunt placement for hepatic hydrothorax, and liver transplantation is the best option. Although this is a severe and rare condition, visiting the doctor when the patient has ascites will help the physician choose the best treatment. A regular check-up with the doctor and monitoring fluid build-up will prevent complications and improve the patient's lifespan.