Author:
Paul J.Allegretti
KeriRobertson
Description
- Pathologic accumulation of serous fluid in the peritoneal cavity
- Portal hypertension (>12 mm Hg) starts fluid retention
- Avid sodium retention state
- Retained sodium and water increases plasma volume
- Water excretion becomes impaired
- Increased release of antidiuretic hormone (ADH)
- Urinary sodium retention, increased total body sodium, and dilutional hyponatremia
- Degree of hyponatremia correlates with disease severity; prognostic factor
- Decreased plasma oncotic pressure from hypoalbuminemia
- Peritoneal irritation owing to infection, inflammation, or malignancy
Etiology
- Parenchymal liver disease:
- Cirrhosis and alcoholic hepatitis:
- Fulminant hepatic failure
- Hepatic congestion:
- CHF
- Constrictive pericarditis
- Veno-occlusive disease and Budd-Chiari syndrome
- Malignancies:
- Peritoneal carcinomatosis
- Hepatocellular carcinoma or metastatic disease
- Infections:
- Hypoalbuminemic states:
- Nephrotic syndrome
- Malnutrition; albumin<2.0 g/dL
- Other conditions:
- Pancreatic ascites
- Biliary ascites
- Nephrogenous ascites
- Ovarian tumors
- Chylous ascites from lymphatic leak
- Connective tissue disease
- Myxedema
- Granulomatous peritonitis
Pediatric Considerations |
| Most pediatric cases owing to: |
Signs and Symptoms
- Abdominal distention, discomfort
- Weight gain; sometimes weight loss
- Dyspnea
- Orthopnea
- Edema
- Abdominal hernias
- Muscle wasting
- Shifting dullness, flank fullness, fluid wave, puddle sign
- Signs and symptoms of underlying disease
- Stigmata of chronic liver disease
History
- Risk factors for liver disease
- Description of onset of symptoms:
- Distinguishes ascites from obesity
- Patients less tolerant of rapid accumulation of ascitic fluid
- New-onset ascites in known cirrhotic signifies 1 of the following:
- Progressive liver disease
- Superimposed acute liver injury (alcohol, viral hepatitis)
- Hepatocellular carcinoma
Physical Exam
- Detection difficult in obese patients
- Flank dullness is a prominent physical finding:
- 500 mL for flank dullness
- Fluid wave
- Shifting dullness
Essential Workup
- Search for liver disease, CHF, TB, malignancy, and other systemic disorders
- Abdominal paracentesis:
- Necessary for:
- New ascites
- Worsening encephalopathy
- Fever
- Abdominal pain/tenderness
- Determine if fluid infected or presence of portal hypertension
- Test ascitic fluid for:
- Cell count and differential:
- Most helpful to determine infection quickly
- Order on every specimen
- Albumin
- Protein
- Gram stain
- Culture twice in blood culture bottles with 10 mL of fluid
- Lactate dehydrogenase (LDH)
- Glucose
- TB culture
- Amylase
- Triglyceride
- Cytology
- Bilirubin
- Carcinoembryonic antigen
- Spontaneous bacterial peritonitis (SBP):
- Ascitic fluid infection without an intra-abdominal surgically treatable source
- Fever, abdominal pain/tenderness, altered mentation
- Polymorphonuclear neutrophils (PMNs) >250 cells/mm3
- Ascitic fluid protein <1 g/dL
- Low concentration of opsonins
- Secondary bacterial peritonitis:
- Bacterial peritonitis from a surgically treatable intra-abdominal source
- Gut perforation or intra-abdominal abscess (i.e., perinephric abscess)
- PMNs >250 cells/mm3 with multiple micro-organisms on Gram stain + 2 of the following found with secondary bacterial peritonitis:
- Total protein >1 g/dL
- Glucose <50 mg/dL
- LDH greater than the upper limit of normal for serum
Diagnostic Tests & Interpretation
Lab
- CBC
- Basic chemistry
- LFTs
- PT, PTT, INR
- Arterial blood gas (ABG) or pulse oximeter
- Urinalysis
- Urine sodium
- Hepatitis panel
- Amylase/lipase
- α-Fetoprotein
- TSH
Imaging
- US:
- Confirm ascites, especially if <500 mL
- Evaluate liver, pancreas, spleen, and ovaries
- Guides paracentesis
- Doppler study: Evaluate hepatic blood flow
- CT scan
- CXR: CHF, effusions, cavitary, or mass lesion
- ECG
Diagnostic Procedures/Surgery
- Peritoneoscopy: Ascites of unknown cause; especially TB
- Paracentesis:
- Clinical diagnosis of SBP without paracentesis is inadequate
- Safety of paracentesis:
- 70% of ascitic patients have coagulopathy
- Benefits of a diagnostic paracentesis outweigh the risks
- Paracentesis is still indicated unless disseminated intravascular coagulation (DIC) is present
- Transfusion of plasma or platelets prior to paracentesis is not supported
Differential Diagnosis
- 1 of the 5 “F” causes of abdominal swelling:
- Fluid (including cysts)
- Fat
- Flatus
- Fetus
- Feces
- Other: Organomegaly
- Serum-ascites albumin gradient (SAAG) = serum albumin - ascitic albumin:
- Replaced ascitic fluid total protein in the differential diagnosis of ascites
- SAAG ≥1.1 g/dL:
- 97% accurate in predicting portal hypertension
- Cirrhosis
- Alcoholic hepatitis
- Cardiac
- Liver metastases
- Fulminant hepatic failure
- Portal vein thrombosis
- Veno-occlusive disease
- Myxedema
- Budd-Chiari
- Fatty liver of pregnancy
- SBP
- SAAG <1.1 g/dL:
- Peritoneal carcinomatosis
- TB
- Pancreatic ascites
- Nephrotic syndrome
- Bowel obstruction or infarction
- Vasculitis
- Postoperative lymphatic leak
Prehospital
Symptomatic hypotension:
- Airway, breathing, circulation (ABCs), IV 0.9 NS
Initial Stabilization/Therapy
Sudden increase in abdominal girth, pain, or fever requires urgent evaluation for possible complicating factor such as:
- Infection
- Hepatoma
- Obstruction of hepatic outflow
- Decompensated liver function
ED Treatment/Procedures
- Successful treatment depends on accurate diagnosis of underlying cause
- Treat underlying cause
- Minimize ascitic fluid and peripheral edema without causing intravascular volume depletion
- Early detection of complications is necessary:
- Spontaneous bacterial peritonitis:
- High degree of suspicion
- Low threshold for paracentesis
- Prompt therapy
- Tense ascites and hydrothorax:
- Abdominal hernias:
- Watch for incarceration, ulceration, or rupture.
- Therapeutic paracentesis
- Surgical consultation
- Persistent leak at paracentesis site:
- Remove more fluid.
- Stomal barrier device
- Meralgia paresthetica:
- Owing to pressure on the lateral femoral cutaneous nerve
- Relieve the pressure by paracentesis or diuresis
- Large-volume paracentesis:
- 5-10 L (100 mL/kg)
- Performed safely in the ED with stable hemodynamics
- Consider replacement with IV albumin (5-10 g/L fluid removed) if >5 L removed.
- Monitor the patient for 8 hr prior to discharge
- Nonparacentesis reduction of ascites:
- Strict sodium restriction:
- <2 g/d
- Restrict water if serum sodium <120-125 mEq/L
- Spironolactone:
- Furosemide:
- Works best for other causes of ascites
- Add to spironolactone in cirrhotics at spironolactone/furosemide ratio of 100 mg/40 mg.
- Add metolazone for less responsive cases
- Diuretic principles:
- Administer diuretics as single morning dose
- Obtain spot-urine sodium to evaluate response
- Patients with urinary Na >10 mEq/L are more responsive to diuretics
- Diuretic-induced weight loss should not exceed 2 lb/day in patients without edema and 5 lb/day in patients with edema
- Monitor electrolytes and renal function
- Avoid hypokalemia since hypokalemia enhances renal ammonia production, precipitating hepatic encephalopathy
- Refractory ascites:
- Accounts for 10% of patients
- Ensure compliance with diet and medications
- Treated with peritoneovenous shunt— transjugular intrahepatic portosystemic shunt
- Liver transplantation
- Avoid NSAIDs:
- Diminish response to diuretics
- Decrease renal plasma flow and GFR
- Cause sodium retention/reduces urinary Na excretion
- Treat underlying cause of ascites owing to conditions other than cirrhosis:
Medication
First Line
- Albumin: 5-10 g/L of fluid removed if >5 L removed
- Cefotaxime: 2 g IV q8h
- Spironolactone: 100-400 mg/d (peds: 1-6 mg/kg) PO in 2 divided doses per day
- Furosemide: 40-160 mg/d (peds: 1-3 mg/kg) PO
Second Line
- Amiloride: 5-20 mg/d PO
- Metolazone: 5 mg/d
- Triamterene: 100-300 mg/d PO in 2 divided doses per day
Disposition
Admission Criteria
- Fulminant liver failure
- Hepatic encephalopathy
- SBP
- Hepatorenal syndrome
- GI bleeding
- Tense ascites not responding to ED treatment
Discharge Criteria
Patients responding to ED management
Follow-up Recommendations
- GI for all new cases
- Primary doctor or GI for previously established cases
- CoreyK, FriedmanL. Harrison's Principles of Internal Medicine. 19th ed.New York: McGraw-Hill; 2016.
- FeldmanM. Sleisenger and Fordtran's Gastrointestinal and Liver Disease. 10th ed.Philadelphia, PA: WB Saunders; 2016.
- RunyonBA; AASLD Practice Guidelines Committee. Management of Adult Patients with Ascites Due to Cirrhosis: An update 2012 . Hepatology. 2013;57(4):1651-1653.
- SuchJ, RunyonB. Ascites in adults with cirrhosis: Initial therapy . UpToDate, 2017.
See Also (Topic, Algorithm, Electronic Media Element)
Cirrhosis