Qualitative and Quantitative Issues in Treating Ascites (Peritoneal Effusion)
With advances in medicine, the medical community's understanding of ascites (peritoneal effusion) has become clearer, and the approach to treating it more precise. Clinicians who frequently see ascites patients in practice should master some "qualitative" and "quantitative" knowledge closely related to ascites, so as to better safeguard patients' health and survival.
First, ascites has many causes; we must have a precise understanding of the cause before we can treat it properly. Ascites is usually caused by viral hepatitis, non-alcoholic steatohepatitis, schistosomiasis, drug-induced hepatitis, autoimmune hepatitis, cholestatic liver disease, cirrhosis, or malignant tumors. It is a complication of the end-stage of chronic progressive diffuse liver disease, often accompanied by abnormal liver function, and in some cases by abnormal renal function. Ascites can be detected by B-ultrasound; other imaging (such as CT) can also detect it, but B-ultrasound is the most commonly used means.
Examination of peritoneal paracentesis fluid can determine the nature of ascites and differentiate its types. Based on appearance, ascites is classified into four types: clear, bloody, purulent, and chylous. Clear ascites is generally transudative; purulent ascites is usually accompanied by infection; bloody and chylous ascites are mostly caused by malignant tumors, and cancer cells can be found in such fluid.
Generally, the appearance of ascites in a malignant tumor (highest among patients with liver cancer, secondary liver tumors, peritoneal mesothelioma, and ovarian cancer) means the patient is already at an advanced stage, and in severe cases at the end stage. Even if the patient has no distant metastatic lesions, cancer patients with ascites are already advanced and have a poor prognosis.
Based on volume, ascites is classified as mild (grade 1), moderate (grade 2), and severe (grade 3). Grade 1 ascites is a small amount, difficult to detect by the naked eye, and generally requires B-ultrasound to find; cancer patients at risk of ascites should therefore have regular B-ultrasound follow-up. Grade 2 ascites is a moderate amount, with visible moderate symmetrical abdominal distension and bulging. Grade 3 ascites is a large or severe amount, with severe abdominal distension and bulging that affects daily life and even makes turning over difficult. Some patients also develop complications such as jaundice, enlarged or shrunken liver and spleen, or abdominal wall varices. Ascites caused by cirrhosis or liver cancer is often accompanied by spider angiomas and liver palms.
Based on the patient's response to treatment, ascites is divided into uncomplicated ascites and refractory ascites. If the patient responds well and ascites resolves quickly, it is uncomplicated ascites. If, despite sodium restriction (daily sodium intake below 90 mmol) and high-dose diuretic therapy for more than 1 week, average daily weight loss is less than 0.8 kg and urinary sodium excretion is less than sodium intake; or if ascites recurs within four weeks after an initial effective response and continued treatment shows little effect; or if diuretics induce hepatic encephalopathy, renal damage, hyponatremia, hypokalemia, or hyperkalemia—all these are refractory ascites. Refractory ascites is difficult to treat and has a poor prognosis.
During ascites treatment, attention must be paid to diet and sodium intake. Because patients with ascites often also have abdominal distension and dyspepsia, the diet should be nutritious and easy to digest, avoid greasy foods, and follow the principle of small frequent meals. Water intake must also be restricted; daily water intake should generally be controlled at around 1500 ml, and may be moderately increased once the condition improves. Patients with concurrent hyponatremia should limit water intake to within 500 ml. Anemic patients may be transfused with whole blood (200 ml per time); those with low plasma protein may receive human albumin (10-20 g per dose); those with amino acid metabolic imbalance may receive daily intravenous infusion of liuhe amino acid (250 ml each, once daily or every other day).
Ascites patients should control sodium intake; a low-salt or salt-free diet is best, with daily sodium controlled at 3-4 g; for refractory ascites, sodium should be limited to 1-1.5 g. Alcohol is strictly prohibited with any type of ascites. For patients with ascites due to cirrhosis or liver cancer, drinking alcohol is no different from suicide. But in practice I have encountered many patients dependent on alcohol; even when such patients develop serious conditions such as cirrhotic ascites, they find it hard to stop drinking, and they are very difficult to treat.
When using diuretics, attention must be paid to dosage. The peritoneum absorbs 100-930 ml of ascites per day, so the amount of ascites removed per day should not exceed 930 ml. During removal, one must not be impatient: rapid diuresis or large-volume paracentesis in a short time causes a sharp drop in effective circulating blood volume, triggering more serious complications such as hepatorenal syndrome and endangering the patient's life. Therefore, during ascites removal, the patient's weight must be monitored. For patients without peripheral edema (such as lower-limb edema), single-day weight loss during treatment should be kept within 300 g; for those with peripheral edema, within 1 kg. Exceeding these figures easily costs more than it benefits.
For mild-to-moderate ascites, TCM treatment is reliably effective and less likely to cause electrolyte disturbances and other adverse reactions, so such patients are recommended to take Chinese herbs. Commonly used herbs to control ascites include Wuling San (Five-Ingredient Powder with Poria), Jinkui Shenqi Wan (Golden Cabinet Kidney-Qi Pill), Zhuling Tang (Polyporus Decoction), and Weiling Tang (Stomach-Calming Poria Powder). Robust non-cancer patients who fail these mild formulas may try Shizao Tang (Ten-Jujube Decoction), Pengzheng Wan (Distention-Relieving Pill), Zhouche Wan (Boat-Vehicle Pill), or Zilong Wan, but these are not recommended for advanced cancer patients.
Viral hepatitis patients who develop ascites, in addition to diuresis, must also take antiviral drugs. Hepatitis B patients may take entecavir, tenofovir, lamivudine, or adefovir dipivoxil; hepatitis C patients may take elbasvir, daclatasvir, velpatasvir, sofosbuvir-velpatasvir tablets, elbasvir-grazoprevir tablets, or glecaprevir-pibrentasvir tablets. TCM treatment may also be combined; patent medicines such as Huachansu (cinobufacin) have a certain inhibitory effect on hepatitis viruses. Patients with liver damage should simultaneously take liver-protecting and bile-promoting drugs; commonly used ones include Atolmoran (reduced glutathione tablets), bicyclol, silybin, and the patent medicines Hugan Pian (Liver-Protecting Tablet) and Fule Kang.
Cancer patients who develop ascites are usually at an advanced stage; diuretics alone are of little use, and anti-cancer drugs should be combined. In fact, some cancer patients with ascites do not need any diuretic at all: once the anti-cancer drugs take effect, the ascites is automatically reabsorbed by the peritoneum. I have treated a liver cancer patient with modified Xiaoyao Wan, a peritoneal mesothelioma patient with Yanghe Tang plus Xihuang Wan, and an ovarian cancer patient with Dahuang Zhechong Wan plus Xihuang Wan; without adding any Chinese or Western diuretic, each patient's ascites gradually resolved. Therefore, the treatment of cancerous ascites should not follow the same approach as non-cancerous ascites. Cancerous ascites should be treated primarily by anti-cancer therapy, with diuresis as a supplement.
Severe ascites patients should receive integrated Chinese-Western medicine: combining TCM syndrome and disease differentiation with potassium-wasting and potassium-sparing diuretics. Commonly used potassium-wasting Western diuretics include hydrochlorothiazide and furosemide (Lasix). Hydrochlorothiazide may be used at 50 mg three times daily; furosemide at 20-40 mg twice daily for 2-3 days. Potassium-sparing diuretics include spironolactone (Aldactone), 40 mg three times daily. Spironolactone acts relatively slowly, taking 3-5 days to show effect. If efficacy is poor and aldosterone is elevated, spironolactone may be increased to a maximum of 300 mg per day. Patients for whom diuretic removal of ascites fails may still have ascites tapped, but the daily tapped volume should preferably not exceed 1000 ml.
Ascites patients should closely monitor liver function indicators. Usually, in patients whose treatment is effective, transaminases, lactate dehydrogenase, albumin, and total protein gradually return to normal; in cancerous ascites patients who respond, tumor markers (carcinoembryonic antigen, alpha-fetoprotein, CA-125, etc.) also decline. Weak ascites patients show reduced serum zinc, iron, and copper; zinc supplementation may improve their condition. Patients with electrolyte disturbances need to control blood sodium and potassium levels.
Integrated Chinese-Western, scientific, and precise treatment of ascites, with careful control of medication intensity, can minimize mortality among ascites patients and reduce doctor-patient disputes.