OVERVIEW

What is ascites?

Ascites, also known as abdominal effusion, refers to the abnormal accumulation of fluid in the peritoneal cavity. The peritoneal cavity is the space in the abdomen outside of organs such as the liver, stomach, and intestines.

Normally, the peritoneal cavity contains a small amount of fluid (usually less than 200 ml) for lubrication and protection.

However, certain diseases can cause an abnormal increase in this fluid, leading to ascites.

The development and progression of ascites largely depend on the treatment of the underlying disease. Depending on the cause, the affected population, treatment methods, and prognosis may vary.

What causes ascites?

Liver diseases such as cirrhosis and liver cancer are the most common causes of ascites. Other conditions include congestive heart failure, kidney failure, ovarian cancer, peritoneal malignancies, hypoalbuminemia, and tuberculous peritonitis.

Ascites caused by malignant tumors is called "malignant ascites," which is a late-stage complication of cancer. It is often accompanied by severe symptoms such as abdominal pain, bloating, loss of appetite, and even difficulty breathing.

Does ascites in a cirrhosis patient indicate a severe condition?

Yes, the presence of ascites in cirrhosis patients marks the transition to the decompensated stage, indicating advanced disease. However, with active treatment, there is still hope for controlling disease progression.

SYMPTOMS

What are the manifestations of ascites?

Mild ascites usually has no symptoms. As the fluid accumulates, symptoms such as abdominal pain, discomfort, and bloating often appear. When a large amount of ascites compresses the diaphragm upward, it can affect chest movement, leading to difficulty breathing.

In terms of body shape and appearance, patients with ascites may exhibit abdominal distension, sometimes even spherical, with tight skin and an increased abdominal circumference. Some patients may also show visibly dilated and protruding veins on the abdominal skin.

What are other common symptoms of ascites?

Ascites caused by different underlying conditions may present with additional symptoms, which are very helpful in determining the cause.

• Ascites accompanied by fever and night sweats often suggests tuberculous peritonitis.

• Ascites with jaundice (yellowing of the skin and eyes) and multiple skin hemorrhages usually indicates chronic liver disease.

• If physical examination reveals hepatomegaly and significant dilation of abdominal wall blood vessels, it suggests portal hypertension.

• Ascites with abdominal pain or masses may indicate abdominal tumors; female patients should also be alert to tumors in the reproductive system, such as ovarian cancer.

• Ascites accompanied by generalized edema may suggest heart failure, malnutrition, or kidney disease.

• Ascites with cyanosis (purple lips or nails) is often a sign of hypoxia, possibly due to heart disease.

What other diseases can ascites cause?

Common complications of ascites include:

• Difficulty breathing or even pleural effusion: Large amounts of ascites can compress the diaphragm, leading to difficulty breathing. In severe cases, it may also cause fluid accumulation in the chest cavity, known as hepatic hydrothorax, usually occurring in severe liver disease.

• Spontaneous bacterial peritonitis (SBP): This mainly occurs in patients with ascites due to cirrhosis and portal hypertension. Normally, the abdominal cavity is sterile, but in portal hypertension, gastrointestinal bacteria may enter the ascitic fluid, causing infection.

• Hepatorenal syndrome: This often occurs in patients with cirrhosis. Due to ascites and liver dysfunction, kidney failure may develop, manifesting as reduced or absent urine output.

What might ascites with swollen feet and difficulty breathing indicate?

Massive ascites can compress the chest cavity, impairing lung expansion and causing difficulty breathing. Therefore, patients with severe ascites often experience breathing difficulties and may require paracentesis to drain some fluid and relieve symptoms.

When accompanied by swollen feet, it indicates that excess fluid has accumulated not only in the abdomen but throughout the body, suggesting a severe condition. Immediate treatment to reduce ascites is necessary, including diuretics, albumin infusion, or therapeutic paracentesis.

CAUSES

How Does Ascites Form?

The fluid in the abdominal cavity is not static but constantly exchanges with blood and lymph, maintaining a dynamic balance of inflow and outflow. Ascites occurs when this balance is disrupted by various factors.

In summary, the following four mechanisms are the main causes of ascites:

• Increased Hydrostatic Pressure in Blood Vessels: Conditions such as heart failure or cirrhosis can raise hydrostatic pressure, which forces fluid from blood vessels into the abdominal cavity. This often occurs due to impaired venous return to the heart, such as portal vein obstruction or increased portal pressure.

• Decreased Plasma Colloid Osmotic Pressure and Low Albumin Levels: In fluid exchange between the abdominal cavity and blood, albumin in plasma counteracts hydrostatic pressure by absorbing fluid back into the bloodstream. Reduced albumin levels (e.g., due to malnutrition, liver failure, or kidney failure) can impair this process, leading to ascites.

• Lymphatic Obstruction: The lymphatic system plays a crucial role in fluid circulation. Blockages in lymphatic vessels (e.g., from tumors, systemic diseases, or radiation therapy) can contribute to ascites.

• Kidney Damage: The kidneys regulate fluid excretion. Reduced renal blood flow or impaired glomerular filtration can cause water and sodium retention, promoting ascites formation.

Is Ascites Caused by Cirrhosis Contagious?

Whether ascites is contagious depends on its underlying cause. Ascites resulting from cirrhosis due to viral hepatitis (e.g., hepatitis B or C) may pose a transmission risk, requiring proper disinfection when handling fluids. However, ascites caused by alcoholic cirrhosis is not contagious.

DIAGNOSIS

What tests are needed for ascites?

• The most important step is the doctor's physical examination of the patient to determine the presence of ascites and estimate its volume, which is the most fundamental and crucial step.

• Abdominal ultrasound or CT scans are highly useful for diagnosing small amounts of ascites.

• Blood tests such as biochemical indicators, liver function, kidney function, and coagulation tests can help identify the cause of ascites.

• Paracentesis, which involves extracting a small amount of ascitic fluid with a needle for testing, aids in both diagnosis and treatment.

How is ascites classified based on volume?

After diagnosing ascites, it is typically graded according to the International Ascites Club's classification system:

• Grade 1 – Mild ascites, detectable only by ultrasound.

• Grade 2 – Moderate ascites, presenting as symmetrical abdominal distension.

• Grade 3 – Large or severe ascites, with significant abdominal distension.

What is paracentesis for ascites?

Paracentesis, often abbreviated as "ascitic tap," is a procedure where a thin needle is inserted into the abdominal cavity to drain ascitic fluid. It is a vital diagnostic tool for ascites and can also be performed after an ultrasound examination.

Why do patients with ascites need paracentesis?

Paracentesis serves two main purposes:

• Diagnostic paracentesis: Used to determine the nature of the ascitic fluid and identify its cause.

• Therapeutic paracentesis: When ascites volume is large, patients may experience bloating, chest tightness, or shortness of breath, requiring fluid drainage to relieve symptoms.

Is paracentesis for ascites safe?

Yes, it is safe. Paracentesis is a well-established procedure that can now be performed under ultrasound guidance. Local anesthesia is applied near the puncture site beforehand, making it a generally painless and safe clinical procedure.

What are transudates and exudates in ascites?

Ascitic fluid can be classified as transudate or exudate based on protein content:

• Transudates appear clear, with a protein content below 25 g/L.
• Exudates often appear cloudy and may be chylous, bloody, or purulent, with protein content usually exceeding 30 g/L.

Certain conditions tend to cause transudates, such as heart failure, cirrhosis, and hypoalbuminemia, while others like tuberculosis or tumors often lead to exudates.

What is the purpose of serum-ascites albumin gradient (SAAG)?

Besides distinguishing between transudates and exudates to identify the cause of ascites, the serum-ascites albumin gradient (SAAG) is commonly used to assess ascites caused by portal hypertension. SAAG is the difference between serum albumin and ascitic fluid albumin measured on the same day. A SAAG ≥11 g/L indicates portal hypertension with an accuracy of up to 97%.

Why are tumor markers tested in patients with ascites?

Tumor markers are useful in differentiating benign from malignant ascites. Common markers include carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), CA-125, and CA19-9.

It's important to note that tumor markers are not 100% reliable for diagnosing malignant ascites. A definitive diagnosis requires combining clinical findings, cytology, and pathological examinations.

What conditions should ascites be differentiated from?

Ascites must be distinguished from other causes of abdominal distension, such as obesity, gastrointestinal bloating, large ovarian cysts, or cysts/fluid accumulation in other organs. Doctors rely on detailed physical examinations, abdominal ultrasounds, or CT scans for differentiation.

TREATMENT

When should a patient with ascites seek medical attention?

Diseases that cause ascites are generally severe. Therefore, if ascites is detected during a physical examination or incidentally, immediate medical attention and treatment are necessary.

Which department should a patient with ascites visit?

The choice of department depends on medical history and accompanying symptoms.

Patients with a history of viral hepatitis, alcoholic hepatitis, tuberculosis, etc., who develop ascites, may visit the general internal medicine or gastroenterology department.

Some female patients with ascites accompanied by irregular menstruation, lower abdominal tenderness, or progressive weight loss may also visit the gynecology department.

Generally, most patients with ascites initially visit the gastroenterology department.

How is ascites treated?

• Addressing the cause: The treatment plan for ascites depends on the underlying cause. Only by addressing the cause can ascites be eliminated at its source.

• Symptom relief: The primary goal is to reduce ascites and alleviate symptoms of abdominal compression, such as breathlessness or chest tightness. Limiting salt and water intake can reduce ascites formation, while diuretics can increase fluid excretion. A common diuretic regimen combines oral spironolactone and furosemide, with initial doses of 100 mg and 40 mg, respectively, taken in the morning. Dosages can be adjusted in a 10:4 ratio based on treatment response, up to a maximum of 400 mg spironolactone and 160 mg furosemide per day. Alternatively, paracentesis may be used to drain ascites.

• Supportive care: Patients with ascites often have severe underlying conditions and may experience weakness or malnutrition, so adequate energy and nutrient intake must be ensured.

Why don't doctors drain ascites even when there is a large amount?

In patients with cirrhosis, ascites is often extensive and causes symptoms like abdominal distension or difficulty breathing, yet doctors are cautious about draining it.

This is because ascitic fluid contains large amounts of protein and electrolytes. Indiscriminate drainage can easily trigger electrolyte imbalances or even hepatic encephalopathy. Additionally, cirrhotic patients often have poor nutritional status, and draining ascites could worsen it.

Therefore, diuretics and supportive care are preferred to manage ascites. If ascites causes severe symptoms like extreme abdominal distension or respiratory distress, paracentesis may be performed after weighing the risks and benefits. Generally, 6–8 g of albumin is recommended for every 1 L of ascites drained, with albumin supplementation becoming more urgent when drainage exceeds 5 L.

How is ascites caused by heart disease treated?

The most important treatment for cardiac ascites is addressing the underlying heart condition, often heart failure. Medications like inotropes, diuretics, and antihypertensives are typically used to temporarily manage heart failure. After stabilization, the root cause of the heart disease should be addressed—for example, mitral valve stenosis may require valve replacement surgery.

Can ascites caused by cirrhosis be completely cured with surgery?

Surgery cannot completely cure cirrhotic ascites. Surgical options, such as splenectomy, shunt surgery, or devascularization, aim to reduce portal hypertension as a last resort. However, if the underlying condition is poorly controlled, portal hypertension may recur, leading to ascites again.

What is refractory ascites in cirrhosis?

"Refractory" refers to ascites that does not respond to high doses of diuretics or causes complications like hepatic encephalopathy, hyponatremia, or hyperkalemia even with low doses.

Are folk remedies for ascites trustworthy?

Many folk remedies claim to cure all diseases, but most are scientifically unfounded. Patients should inform their doctors about any medications, including herbal remedies or supplements, and use them only under medical supervision. Otherwise, they may worsen the condition and lead to serious consequences.

DIET & LIFESTYLE

How to determine if ascites has increased?

Monitoring body weight and waist circumference are common and simple methods to assess whether ascites has increased. Weight monitoring is best performed at a fixed time each day, either before or after meals.

What should cirrhosis patients with ascites pay attention to in daily life?

• Bed rest.

• Strictly avoid alcohol. Alcohol is metabolized by the liver, and drinking can worsen cirrhosis.

• Avoid medications that require liver metabolism, such as those containing acetaminophen.

• Limit salt and water intake.

• Take diuretics under medical supervision to reduce ascites.

What should cirrhosis patients with ascites pay attention to in their diet?

Cirrhosis is a chronic wasting disease, and substantial evidence shows that nutritional therapy is beneficial for patients. In terms of diet, patients should consume high-calorie, high-protein, and easily digestible foods, such as lean meat, fish, soy products, milk, vegetables, and fruits. Patients with esophageal varices must avoid rough or hard foods.

PREVENTION

How to prevent ascites?

Ascites is not an independent disease but often a complication of other serious conditions such as cirrhosis, heart failure, or tuberculosis. Therefore, actively treating the underlying disease can prevent the occurrence of ascites.

For healthy individuals, maintaining a healthy lifestyle is sufficient. Avoid smoking; exercise regularly and avoid prolonged sitting. Prevent overweight and obesity by engaging in moderate exercise 3-5 times per week, with each session lasting about 30 minutes, combining aerobic and strength training without excessive intensity. Ensure adequate sleep daily, regardless of early or late bedtime. Learn to manage stress and emotional tension. Maintain a balanced and nutritious diet.