Refractory Ascites: An Overview

Introduction:

Refractory ascites is reappearing ascites that occur after removing the fluid build-up in the abdomen after a few days. This condition is also seen in patients who take a low-sodium diet and patients under diuretics medication (a drug that reduces blood pressure). The symptoms of refractory ascites are abnormal enlargement of the stomach and pain in the abdominal region. This condition is ruled out with physical findings. Medications and liver transplantation treat refractory ascites.

What Are the Causes of Ascites?

Ascites is an abnormal accumulation of fluid in the abdominal region. Three theories throw light on how ascites are formed.

1. Overflow: This theory explains the blood volume or extracellular volume build-up that results due to the reabsorption of sodium in the proximal and distal tubules. Proximal and distal tubules are components of nephrons. A nephron is the structural and functional unit of the kidneys. In addition, the renin-angiotensin-aldosterone mechanism and sympathetic nervous system are also activated. Renin-angiotensin-aldosterone system (RAAS) is a hormone system that manages blood pressure, electrolyte fluid balance, and vascular resistance.

The sympathetic nervous system activates adrenaline and noradrenaline, resulting in high heart rate, elevated blood pressure, and increased breathing rate, eventually increasing sodium retention.

2. Underfill: This theory explains that an increase in the portal pressure in an already prevailing portal hypertension condition causes dilation of the splanchnic blood vessels (blood vessels that supply the abdominal region). This causes elevated levels of portal venous blood and lymph formation (interstitial fluid build-up in small capillaries), which further causes leakage into the abdominal cavity.

The dilation of splanchnic blood vessels reduces the arterial blood volume, which activates certain receptors that trigger sympathetic nervous system activation and the renin-angiotensin-aldosterone mechanism. This reaction ultimately results in sodium retention.

3. Peripheral Arterial Vasodilation: The high pressure in the portal vein causes vasodilation (widening of blood vessels) and decreases the capacity of the arterial blood flow. This activates the neurohormonal response, which causes changes in the kidney, heart, and vascular system (blood vessels). Thus it causes retention of renal sodium and increases plasma volume build-up.

Sodium keeps hold of water in the body. The plasma is made of 90 % water, salts, lipids, and hormones. The blood volume consists of 55 % of plasma. This chain reaction leads to the accumulation of fluid in the abdomen.

What Is Refractory Ascites?

Refractory ascites occur when the ascites appear again in the patient under treatment with medications to lower the blood pressure, who take a low salt (sodium) diet to reduce the risk of water retention, and after fluid drainage from the abdomen.

What Causes Refractory Ascites?

• Chronic liver diseases like cirrhosis (scarring of healthy liver tissues).

• Not responding to diuretic treatment.

What Are the Symptoms of Refractory Ascites?

• Enlarged abdomen due to fluid accumulation.

• Pain in the stomach (abdomen).

• Feeling full with minimal food or fluid intake.

How Are Refractory Ascites Ruled Out?

The below-mentioned factors help find out refractory ascites in a patient:

• Abnormally enlarged stomach.

• No response to diuretic medication with the minimum dose for one week.

• Complications like hyponatremia (low sodium level in the blood), hypokalemia (low potassium levels in the blood), or azotemia (increased levels of urea and nitrogenous products) are induced by diuretics without any other factors that cause the disease.

• Recurrence of ascites within four weeks of fluid drainage.

• Continuous occurrence of ascites with restriction in sodium intake.

• The excretion of sodium in the urine is less than sodium intake.

• Weight loss with less than 0.8 kilograms in four days.

How Are Refractory Ascites Treated?

There is no cure for refractory ascites, but certain management can diminish the symptoms.

• Diuretics: Diuretics are medications used to reduce blood pressure. This medication removes extra sodium and water present in the body through urine. The sodium eliminates water in the blood, which causes a reduction of fluid volume in the blood vessels. This causes the blood pressure to reduce.

• Spironolactone: Spironolactone is combined with other antihypertensive drugs to reduce blood pressure. This medication acts by removing increased amounts of sodium and water in the urine, thus leading to a diuretic action and reducing blood pressure.

• Low Salt Intake: A low salt (sodium) diet is recommended.

• Transjugular Intrahepatic Portosystemic Shunts (TIPS): TIPS is a minimally invasive procedure that involves placing a stent connecting the portal vein and the hepatic vein. A tiny opening is made on the right side of the neck to enter the jugular vein (a large blood vessel in the neck that carries blood from the face and head). Next, a vascular sheath (a thin tube used to access a blood vessel) is inserted. It enters the inferior vena cava (a blood vessel that carries blood from the lower limbs and abdomen to the heart), through which the hepatic vein is accessed. The portal vein is accessed by puncturing the liver, and a wire is placed to join both veins. This region is widened, and a stent (a minute tube placed in hollow structures) is set, creating a connection between the portal vein and the hepatic vein.

• Liver Transplant: Liver transplantation is the curative treatment modality in refractory ascites. A whole, healthy liver or a part of a healthy liver is replaced in the diseased patient.

What Are the Complications of Refractory Ascites?

• Hepatic Hydrothorax: It is a condition where there is fluid build-up in the layer connecting the lungs and the chest.

• Spontaneous Bacterial Empyema: Spontaneous bacterial empyema is an infection in the fluid accumulated in the space middle of the lungs and the chest.

• Hepatorenal Syndrome: This condition causes kidney failure due to severe liver disease.

• Hyponatremia: Low sodium levels in the blood.

• Spontaneous Bacterial Peritonitis: Spontaneous infection of the ascites without spreading infections from the stomach or intestines.

• Umbilical Hernia: This is a condition when an intestinal part protrudes at the belly button.

What Is the Prognosis of Patients With Refractory Ascites?

The prognosis is poor, with up to a 50 % survival rate of one year. In addition, old-aged patients over 60 years, patients with diabetes, and patients with hepatocellular carcinoma have poor survival rates.

Conclusion:

Refractory ascites are common in patients with cirrhosis (scarring of the liver). It reappears with repeated fluid drainage and taking medications like Diuretics and low salt intake. As a result, the patients have an abnormally enlarged stomach and pain in the abdomen. This happens when the body is not in a state to remove the accumulated fluid. Treatments like diuretic therapy, no salt intake, and transjugular intrahepatic portosystemic shunts reduce the severity of the symptoms but do not cure them completely. Though the outcome of the disease is poor, liver transplantation is the only method that cures refractory ascites and improves the patient's lifespan.