Ascites

•  Dr.K.T.S
•   Gastero-enterology
• on May, 29, 2013
•  1 Comment.

Ascites

The term Ascites defines fluid accumulation in the peritoneal cavity.The condition is also known as peritoneal cavity fluid, peritoneal fluid excess, hydroperitoneum or more archaically as abdominal dropsy.The abnormal intraperitoneal accumulation of a fluid containing  large amounts of protein and electrolytes .Ascites may be accompanied by the general abdominal swelling,hemodilution,edema or a decrease in urinary output. Ascites is a complication of  cirrhosis, congestive heart failure,nephrosis,malignant neoplastic diseases, peritonitis or various fungal and parasitic diseases.

Causes of abdominal distension(9 Fs.)

    Full bladder                                        Fat

   Firm mass                                             Faeces

(Spleen, kidney, liver, ovary)       Flatus

   Fatal growths                                     Fetus

   Fluid                                                      False pregnancy

Causes of Ascites

Common causes (5Ps)

       Peritonitis (T.B. Malignant)

       Portal hypertension (Cirrhosis)

       Pump failure (CHF)

       Protein deficiency or loss (Nephrosis)

       Pericarditis (Constrictive)

Uncommon Causes of Ascites

     Aneurin deficiency

    Biliary

   Chylous

   Dropsy (epidemic)

  Endocrine             :         Myxoedema

  Female disorder    :         Ovarian (Meig’s syndrome),

Endometriosis, struma ovari

  Glandular             :         Pancreatic

Signs and symptoms of Ascites

Mild ascites is hard to notice, but severe ascites leads to abdominal distension. Patients with ascites generally will complain of progressive abdominal heaviness and pressure as well as shortness of breath due to mechanical impingement on the diaphragm. Signs of ascites may be present due to its underlying etiology. For instance, in portal hypertension (perhaps due to cirrhosis or fibrosis of the liver) patients may also complain of leg swelling, bruising, gynecomastia, hematemesis, or mental changes due to encephalopathy. Those with ascites due to cancer (peritoneal carcinomatosis) may complain of chronic fatigue or weight loss. Those with ascites due to heart failure may also complain of shortness of breath as well as wheezing and exercise intolerance.

Ascites with minimal oedema of feet  (5 Cs)

      Constrictive pericaditis

     Cirrhosis

     Cardiomyopathy (Restrictive)

     Cruveilhier – Banumgarten syn

     C(K)och’s peritonitis

Cirrhotic ascites   

Subtract concentration of ascetic fluid albumin from serum albumin : a serum ascites albumin gradient of > 1.1g/ l predicts hypertension with great accuracy.

Classification of Ascites

Ascites exists in three grades
Grade 1: mild, only visible on ultrasound and CT
Grade 2: detectable with flank bulging and shifting dullness
Grade 3: directly visible, confirmed with fluid thrill

Hemorrhagic fluid                   Chylous fluidTrauma                                     Trauma to thoor. DuctTuberculosis                              TuberculosisTumor                                      Tumor invading thor. DuctThrombosis of                           Thrombosis of subclavian veinMesenteric artery                      Tropical dis. (Filaria)

Diagnosis of Ascites

Complete hemogram,basic metabolic profile, liver enzymes assesment, and coagulation should be performed. A diagnostic paracentesis  to be performed if the ascites is new or if the patient with ascites is being admitted to the hospital. The fluid is then reviewed for its gross appearance, protein level, albumin, and cell counts (red and white). Additional tests will be performed if indicated such as Gram stain and cytopathology.

 

The Serum-Ascites Albumin Gradient (SAAG) is probably a better discriminant than older measures (transudate versus exudate) for the causes of ascites. A high gradient (> 1.1 g/dL) indicates the ascites is due to portal hypertension. A low gradient (< 1.1 g/dL) indicates ascites of non-portal hypertensive etiology.

Ultrasound scan is often performed prior to attempts to remove fluid from the abdomen. Study may reveal the size and shape of the abdominal organs.

 

Doppler studies may show the direction of flow in the portal vein, as well as detecting Budd-Chiari syndrome and portal vein thrombosis. Additionally, the Radiologist can make an estimation of the amount of ascitic fluid, and possible difficulties to drain the fluid may be assesed.That may be drained under ultrasound guidance. Abdominal CT scan is a more accurate alternate to reveal abdominal organ structure and morphology.

Treatment of Ascites

Ascites is generally treated while an underlying etiology is sought, in order to prevent complications, relieve symptoms, and prevent further progression. The goal is weight loss of no more than 1.0 kg/day for patients with both ascites and peripheral edema and no more than 0.5 kg/day for patients with ascites alone. In those with severe ascites causing a tense abdomen, hospitalization is generally necessary for paracentesis.

Life style modification

Avoiding alcohol

Lowering salt in your diet (no more than 1,500 mg/day of sodium)

Salt restriction is effective in about 20% of patients.Salt restriction is the initial treatment, which allows diuresis (production of urine) since the patient now has more fluid than salt concentration.

Limiting fluid intake

Water restriction is needed if  hyponatremia < 130 mmol per liter develops.

Diuretics aldosterone is one of the hormones that acts to increase salt retention, a medication that counteracts aldosterone should be sought. Spironolactone or other distal-tubule diuretics such as triamterene or amiloride is the drug of choice since they block the aldosterone receptor in the collecting tubule. This choice has been confirmed in a randomized controlled trial.Diuretics for ascites should be dosed once per day.Generally, the starting dose is oral spironolactone 100 mg/day (max 400 mg/day). 40% of patients will respond to spironolactone. For nonresponders, a loop diuretic may also be added and generally, furosemide is added at a dose of 40 mg/day (max 160 mg/day), or alternatively bumetanide or torasemide. The ratio of 100:40 reduces risks of potassium imbalance.Serum potassium level and renal function should be monitored closely while on these medications. can be monitored by weighing the patient daily.Diuretic resistance can be predicted by giving 80 mg intravenous furosemide after 3 days without diuretics and on an 80 mEq sodium/day diet.

In those with severe (tense) ascites, therapeutic paracentesis (Inserting a tube into the belly to remove large volumes of fluid) may be needed in addition to medical treatments listed above. As this may deplete serum albumin levels in the blood, albumin is generally administered intravenously in proportion to the amount of ascites removed. Paracentesis is not a treatment choice to give permanent solution.Various types of shunts also available,that are portacaval shunt, peritoneovenous shunt, and the transjugular intrahepatic portosystemic shunt (TIPS)

People with end-stage liver disease may need a liver transplant.

In United States the MELD Score is used to prioritize patients for transplantation.The Model for End-Stage Liver Disease, or MELD, is a scoring system for assessing the severity of chronic liver disease. It was initially developed to predict death within three months of surgery in patients who had undergone a transjugular intrahepatic portosystemic shunt (TIPS) procedure,[1] and was subsequently found to be useful in determining prognosis and prioritizing for receipt of a liver transplant.[2][3] This score is now used by the United Network for Organ Sharing (UNOS) and Eurotransplant for prioritizing allocation of liver transplants instead of the older Child-Pugh score

MELD  score calculation method

MELD = 3.78[Ln serum bilirubin (mg/dL)] + 11.2[Ln INR] + 9.57[Ln serum creatinine (mg/dL)] + 6.43.

Complications of Ascites

Spontaneous bacterial peritonitis (SBP)

Portal vein thrombosis and Splenic vein thrombosis.Clotting of blood affects the hepatic portal vein or varices associated with splenic vein. This can lead to portal hypertension and reduction in blood flow. When a liver cirrhosis patient is suffering from thrombosis, it is not possible to perform a liver transplant, unless the thrombosis is very minor. In case of minor thrombosis, there are some chances of survival using cadaveric liver transplant.