Ascites is the build-up of additional fluid in the abdomen, otherwise called the peritoneal cavity. In mild cases, this extra fluid may not be easily observed, but in more serious cases, the abdomen protrudes greatly, thus providing easy diagnosis of ascites.
Inside the abdomen is a membrane called the peritoneum, which has two layers. One layer lines the abdominal wall and the other layer covers the organs inside the abdominal cavity. The peritoneum
produces a fluid that acts as a lubricant and allows the abdominal organs to glide smoothly over one another. Sometimes too much of this fluid can build up between the two layers, and this is called ascites.
Ascites is most often caused by cirrhosis of the liver, generally related to alcoholism. The "beer belly" referred to by many may actually be ascites. Heart failure can lead to accumulation of fluid in the abdomen as well as in the ankles, wrists, feet and hands. Tuberculosis, pancreatitis and cancer of the abdomen can also produce ascites.
The greater the accumulation of fluid, the greater pressure on the diaphragm, which can cause shortness of breath. Most other symptoms associated with ascites relate directly to its underlying causes. For example, a person with ascites who also has persistent coughing and fever may be evaluated for tuberculosis. Yellow discoloration of the skin and mucus membranes, or jaundice, indicates liver dysfunction as the cause of ascites.
The list of causes of ascites begins with the liver. Regardless of the reason for liver failure, a malfunctioning liver cannot make enough protein to maintain oncotic pressure to keep fluid in the circulatory system.
Causes of ascites due to liver problems include:
Cirrhosis describes a form of liver failure in which liver tissue that is damaged is replaced by scar tissue. As more liver tissue is lost is progressive liver failure occurs. Alcoholic liver disease or alcoholic hepatitis (hepar = liver + it is = inflammation), viral hepatitis (B or C), and fatty liver disease are the most common causes for cirrhosis.
Acute liver failure can result in ascites. This may be due to any acute injury to liver cells including adverse reactions to medications or drug abuse (for example, liver failure is the major consequence of acetaminophen overdose).
Budd-Chiari syndrome is caused by the blockage of the hepatic veins (those that drain the liver). This causes the triad of ascites, abdominal pain, and hepatosplenomegaly (enlargement of the liver and spleen).
Cancer that has metastasized or spread to the liver can also be the source of ascites.
If cancer cells have spread to the lining of the abdomen, they can irritate it and cause fluid to build up.
If the liver is affected by cancer cells, this may block the circulation of blood through the liver, which can lead to a build-up of fluid in the abdomen.
If the liver is damaged, it may produce less blood protein. This may upset the body's fluid balance, which causes fluid to build up in the body tissues, including the abdomen.
Cancer cells can block the lymphatic system. This is a network of fine channels that runs throughout the body. One of its functions is to drain off excess fluid, which is eventually gotten rid of in the urine. If some of these lymphatic channels are blocked, the system can't drain efficiently and fluid can build up.
Other causes of ascites include:
Heart failure is the inability of the heart muscle to adequately pump the fluid within the blood vessels. This can cause a variety of problems, but most notably, fluid backs up into the lungs and other organs causing them to fail. This water overload can cause leakage into the peritoneal cavity and the formation of ascites.
Nephrotic syndrome, in which kidney damage causes protein to leak into the urine, decreases oncotic pressure and may result in ascites.
Disorders of the pancreas can result in ascites in a variety of ways. Acute pancreatitis (inflammation of the pancreas) can cause fluid accumulation as part of the inflammatory response. Chronic pancreatitis can result in malnutrition, leading to decreased total body protein, loss of oncotic pressure, and ascites. Pancreatic cancer can cause direct fluid loss.
Direct irritation of the peritoneum can cause it to leak fluid as part of the inflammation process. This irritation may be due to a malignancy (cancer) or infection.
Diseases of the ovary can be associated with ascites. Cancer of the ovary has no initial symptoms, and many women will have the diagnosis made because they develop ascites. Meigs syndrome is a benign tumor of the ovary called a fibroma that presents with ascites and pleural effusion (fluid in the cavities surrounding the lungs). The hard surface of an ovarian tumor may cause significant irritation of the peritoneum, causing it to leak fluid.
Ascites is found uncommonly in hypothyroidism (low thyroid function). Usually the hypothyroidism has been untreated for a prolonged period of time, and the ascites resolves when thyroid levels in the body return to normal.
The main symptom of ascites is a swollen or distended abdomen due to fluid buildup. Other symptoms may include:
Abdominal pain or discomfort
Ankle swelling
Jaundice (yellowing of the skin and whites of the eyes)
Shortness of breath
Unexplained weight gain
The symptoms of ascites can be very distressing. The abdomen becomes very swollen and distended, which can be uncomfortable or painful. Ascites can also make it difficult for you to get comfortable, sit up or walk. It can make you feel very tired (lethargic) and breathless. It may cause feelings of sickness (nausea) or make you be sick (vomit). You may also suffer indigestion and a reduced appetite.
Ascites is a very serious condition that often indicates cirrhosis of the liver, advanced liver disease, congestive heart failure, cancer, or other life-threatening conditions and complications. Seek immediate medical care (call 911) if you, or someone you are with, have any of these symptoms:
Bleeding, such as vomiting blood, bloody stools or major rectal bleeding
Chest pain or discomfort
Confusion, disorientation, or change in consciousness, such as lethargy, decreased alertness, unresponsiveness or passing out
Loose, wet cough with frothy phlegm and possibly blood-tinged phlegm
Personality changes and poor cognitive functioning due to the inability of the liver to filter toxins and a buildup of waste products in the blood and brain
Shortness of breath, difficulty breathing, wheezing, or other unusual breathing noises
Complications of ascites and the underlying causes of ascites are serious and life threatening. You can help minimize your risk of serious complications by following the treatment plan you and your health care professional design specifically for you. Complications of ascites include:
Esophageal varices
Heart failure
Hepatic encephalopathy
Hepatic hydrothorax
Hernia
Kidney failure
Liver cancer
Liver failure
Malnutrition and weight loss
Permanent liver damage and loss of normal liver function
Spontaneous bacterial peritonitis
In general, unexplained abdominal swelling for any cause is a reason to seek medical care.
For those who have known ascites, fever and abdominal pain should be a warning that the fluid may be infected and care should be accessed immediately.
Excess fluid in the abdominal cavity can cause significant discomfort and shortness of breath. The method of treatment depends upon the reason for the ascites accumulation, how quickly the fluid has accumulated, whether it is a first occurrence or a repeated event, and how significantly the symptoms affect the patient.
Treatment of ascites can include:
Antibiotics to treat an infection called bacterial peritonitis (infection of the lining that surrounds the abdominal organs)
Decreased consumption of high-sodium foods and beverages to reduce fluid retention
Diuretics (such as triamterene) to reduce fluid retention
Paracentesis to remove ascites fluid with insertion of a tube
Placement of a TIPS (transjugular intrahepatic portosystemic shunt) to treat ascites caused by portal hypertension. The shunt allows blood to bypass a damaged liver. TIPS placement is a minimally invasive procedure performed through the jugular vein in the neck.
Ascites is most commonly caused by cirrhosis of the liver. Treatment of cirrhosis includes efforts to stop or slow the progression of damage to the liver and minimize and quickly treat any complications, such as liver failure and hemorrhage. Treatment for liver failure may include liver transplant, which is a major surgical procedure to replace a severely diseased liver with healthy donor liver.
Treatment plans for cirrhosis of the liver also involve treating the underlying cause of the cirrhosis. For example:
Treatment of alcoholism includes abstaining from alcohol, which often requires participation in an alcohol treatment program.
Treatment of hepatitis may include corticosteroid drugs for autoimmune hepatitis or the medication interferon to treat a hepatitis infection.
In order to relieve symptoms, the treatment of ascites involves slowing the build-up of the fluid and putting a tube into the abdomen to drain it (known as paracentesis).
The ascitic tube (drain) is usually inserted by a doctor, and the procedure can be done in the ward or outpatients clinic. Sometimes the drain is put in while you are having an ultrasound scan, which helps show the doctor where to position the drain.
Once you're lying down comfortably, the skin in the area where the drain is to be inserted is cleaned. The doctor then gives you an injection of local anesthetic to numb the area and stop the procedure from being painful.
The doctor makes a very small cut in the skin of the abdomen and inserts a thin tube called a cannula. The cannula is attached to a tube and drainage bag. The ascitic fluid drains out of the abdomen and collects inside the drainage bag. The cannula may be held in place with a couple of stitches and covered with a dressing.
The length of time that the drainage tube needs to stay in place depends on the amount of fluid that needs to be drained off. Sometimes a small amount of fluid can be drained in the outpatients clinic. If there is a large amount of fluid however, the procedure may need to be carried out in hospital under the supervision of the doctors and nurses, and the drain may stay in place for 2–3 days.
It's possible for the ascites to build up again, and drainage may need to be carried out more than once.
For patients with liver disease as the cause of cirrhosis, abstention from alcohol is an important first step in treatment to minimize further liver damage. Acetaminophen-containing medications should be avoided since they require metabolism in the liver.
For patients with cirrhosis, the initial therapy for ascites begins with dietary salt restriction and medications to assist the body in ridding itself of excess salt and fluid. Spironolactone (Aldactone) is a first line diuretic medication that helps block the chemical aldosterone which is responsible for salt retention in the body. Furosemide (Lasix) and metolazone (Zaroxolyn) may also be added. This treatment is effective in controlling ascites fluid in the vast majority of patients.
Body weight is used as a measurement of ascites control. The goal for diuretic therapy is to lose between one to two pounds of weight per day depending upon underlying medical conditions. Once most of the ascites fluid is gone, medication dosing will be individualized to the patient's needs.
Water restriction may be considered if hyponatremia, (low serum sodium) is present.
Other Treatments
Paracentesis: If diuretics and diet fail, paracentesis may be the next step in the treatment offered. Under sterile conditions, a needle is placed into the peritoneal space and fluid is withdrawn. Paracentesis may be considered as a first step if the ascites fluid accumulates quickly and the abdominal distension causes pain or shortness of breath. Because the peritoneal fluid contains albumin, if large amounts of fluid (more than 5 liters) are withdrawn, an albumin transfusion may be needed.
Paracentesis may be done more than once, but if it becomes a frequent necessity for symptom control, other options may be considered.
The complications of paracentesis include infection, bleeding, electrolyte disturbances, and perforating an organ such as the intestine. However, in tense ascites, the benefits outweigh the risks in providing relief to the patient.
Transjugular intrahepatic portosystemic shunt (TIPS): TIPS diverts fluid from the portal vein into the central blood circulation, thus decreasing pressure in the liver and decreasing ascites formation. An interventional radiologist is able to thread a catheter or stent underneath the skin from the internal jugular vein to the hepatic vein while the patient is sedated.
Liver transplant: Patients who have cirrhosis and ascites should be considered as candidates for potential liver transplantation.
Cancer: In patients with ascites from cancer, diet restrictions and diuretics are not effective. Paracentesis may be the first-line treatment. If needed, the catheter maybe left in place to drain, so that fluid can be removed as needed and the patient does not need to undergo repeated procedures.
Peritoneovenous shunting: Peritoneovenous shunting is a surgical operation that may increase short-term survival in cancer patients who are not candidates for, or who have failed treatment with, paracentesis. Shunting may be also considered for patients who have refractory ascites and are not candidates for paracentesis, liver transplant, or a TIPS procedure.