Hydrothorax is a pleural effusion syndrome caused by the accumulation of fluid of non–inflammatory origin (transudate). It is accompanied by heaviness in the chest, shortness of breath, cyanotic skin tone, decreased exercise tolerance. Possible combination with hydropericardium, ascites. Hydrothorax is diagnosed according to echography of pleural cavities, lung X-ray, diagnostic puncture. Treatment involves evacuation of pleural effusion on the background of diet, drug pathogenetic therapy or surgical treatment of the underlying disease.
J94.8 Other specified pleural conditions. Hydrothorax
Unlike pleurisy, in which the effusion has an inflammatory origin (exudate), with hydrothorax, non-inflammatory fluid (transudate) accumulates in the pleural cavity. Pleural effusions of various genesis are diagnosed in 5-10% of patients in therapeutic hospitals. About 30-40% of them account for cardiogenic hydrothorax.
The formation of pleural transudate is always secondary to the underlying disease. In most cases, hydrothorax accompanies decompensated cardiovascular pathology, less often – diseases of the liver, kidneys, endocrine system, mediastinum. Among the main etiofactors are:
- Chronic heart failure. Right ventricular HF may be associated with coronary artery disease, heart defects, constrictive pericarditis, myocarditis, COPD. The accumulation of transudate in the interpleural space occurs due to venous stagnation in the great circle of blood circulation.
- Nephrotic syndrome. It is a consequence of glomerulonephritis, kidney amyloidosis, collagenosis, toxic nephropathy, etc. Against the background of hypoproteinemia and hypoalbuminemia, generalized edema, hydropericardium, hydrothorax, ascites develop. A similar mechanism of pleural effusion formation is characteristic of alimentary dystrophy.
- Cirrhosis of the liver. Hydrothorax develops in 5-10% of patients in the terminal phase of cirrhosis of the liver. It is caused by hypoalbuminemia, portal hypertension, concomitant ascites.
- Peritoneal dialysis. During this procedure, hydrothorax occurs due to the movement of the dialysis solution from the abdominal cavity to the pleural. At the same time, 90% of cases occur on the right-hand hydrothorax.
- Tumors. Neoplasms of the mediastinum, compressing the lymphatic and venous highways, contribute to the development of ERW syndrome, hydrothorax. Among mediastinal neoplasms, teratomas, lymphomas, thymomas, dermoid cysts are leading. Polyserositis, including pleural effusion, occurs in patients with Meigs syndrome.
- Mixedema. The mechanism of transudate formation in severe hypothyroidism is unknown. It is assumed that this is due to the stagnation of lymph due to the low content of thyroid hormones.
- PE. With pulmonary embolism, effusion can have both the character of a transudate and an exudate. The first is characteristic of an acute pulmonary heart, the second – for a lung infarction.
The mechanisms of accumulation of pleural transudate may be different. Stagnant effusions are formed as a result of an increase in hydrostatic pressure in the systemic circulation. This mechanism is implemented in case of ineffective cardiac activity ‒ right ventricular or biventricular insufficiency. Venous stagnation creates conditions for increasing production and reducing transudate resorption. In more than 80% of patients with CHF, effusion has bilateral localization. Transudate is more often serous, less often – serous-hemorrhagic.
Dysproteinemic hydrothorax is formed with renal, hepatic, protein-energy insufficiency. Due to hypoalbuminemia, the oncotic plasma pressure decreases, fluid transudation from the vascular bed into the body cavities and interstitial spaces occurs. In nephrotic syndrome, effusion is more often bilateral.
Hydrothorax in peritoneal dialysis, cirrhotic ascites develops as a consequence of the direct movement of fluid from the abdominal cavity through the slit spaces of the diaphragm into the thoracic cavity. A number of factors contribute to this: an increase in intra-abdominal pressure, a pressure gradient between the abdominal and pleural cavities, a decrease in oncotic pressure. Hepatic hydrothorax in 85% of cases has a right‒sided localization, in 13% – left-sided, in 2% of patients – bilateral. Hydrothorax in mediastinal neoplasia is associated with vascular compression, causing local disruption of lymph and blood flow.
Transudate is a transparent colorless or slightly yellowish liquid. It is characterized by a specific gravity of <1015, a protein content of <30 g / l, a negative reaction of Rivalt. The amount of transudate in hydrothorax varies from 100 ml to 1 liter or more, which determines the severity of the clinical picture. The accumulation of effusion between the pleural leaves causes compression of a part of the lung and the development of respiratory failure.
By localization, pleural effusions are divided into unilateral (right- and left-sided) and bilateral (bilateral). Bilateral effusions can be symmetrical and asymmetrical. Taking into account the amount of transudate ,hydrothorax is distinguished:
The clinic develops gradually or relatively quickly, depending on the rate of accumulation of transudate in the thoracic cavity. The most characteristic sign of hydrothorax is increasing shortness of breath: at first it appears only during physical activity, then it becomes constant and worries at rest. Sometimes there is a dry cough, the cervical veins swell. The appearance of peripheral edema, ascites, hydropericardium, anasarca is possible.
Diffuse cyanosis, acrocyanosis is noted. Chest pain on the side of the hydrothorax is not a permanent sign, it appears mainly with an increase in fluid volume and at the stage of resorption. There may be smoothness or bulging of the intercostal spaces on the side of the lesion. Patients note that it is easier for them to lie on their sick side or be in a semi-sitting position. With acute intense hydrothorax, severe respiratory failure, arterial hypotension develops. Fever is not typical for uncomplicated hydrothorax.
Patients with hepatic hydrothorax may have peritonitis, which serves as a source of secondary infection of pleural effusion, or spontaneous bacterial empyema of the pleura. These conditions should be suspected if a patient with cirrhosis and pleural effusion has fever with chills, chest and abdominal pain. Persistent and progressive nephrotic syndrome for 3-10 years leads to CRF.
Massive or rapidly increasing hydrothorax can cause lung collapse, severe respiratory disorders and death. Hydrothorax always indicates decompensation of the underlying disease and can serve as a predictor of its unfavorable course.
The presence of effusion is indicated by the physical examination data and the patient’s current complaints. The initial examination is carried out by a general practitioner or a pulmonologist, further management of patients is carried out by a specialized specialist: cardiologist, hepatologist, nephrologist, endocrinologist.
Characteristic objective signs are tachypnea, asymmetry of the chest, restriction of mobility of the affected side when breathing. A dull percussive sound is noted above the place of accumulation of fluid, breathing is weakened or not listened to. The following diagnostic algorithm is used to confirm the hydrothorax:
- Ultrasound of pleural cavities. Sonography allows you to detect the presence of even a minimal volume of effusion in the thoracic cavity, to determine its amount with high accuracy. In addition, ultrasound is used for marking and monitoring during pleural puncture.
- Lung x-ray. An X-ray sign of pleural effusion is a homogeneous darkening of the pulmonary fields with an oblique upper boundary of the fluid. In the presence of a unilateral hydrothorax, the shadow of the mediastinum shifts to the healthy side. To exclude changes in the lungs, pleura, mediastinum, chest MSCT is indicated.
- Diagnostic puncture. Pleural puncture has a dual purpose: obtaining an effusion for its further analysis and removing excess fluid from the pleural cavity in order to reduce respiratory dysfunction. Pleural effusion is subject to microscopic, cytological, biochemical, bacteriological examination.
- Additional studies. To find the cause of hydrothorax, it is advisable to perform ultrasound of the abdominal cavity and kidneys, mediastinum, thyroid gland. If CHF is suspected, an EchoCG, electrocardiography is performed. From the methods of laboratory diagnostics, a general urine analysis, blood biochemistry (CSF, albumin, electrolytes, liver enzymes, creatinine, urea, etc.), hormonal studies (thyroid profile) can be shown.
When obtaining data for the presence of pleural effusion, it is important to differentiate its nature (transudate or exudate) and exclude other similar conditions:
To do this, first of all, it is necessary to determine the cause of the appearance of pathological contents (trauma, infection, tumor process, etc.).
The main principles of therapy are the elimination of pleural effusion and correction of the root cause of the pathological condition. In order to reduce respiratory disorders, discharge punctures or permanent drainage of the pleural cavity are performed. Further treatment is selected taking into account the underlying disease.
In all cases, a therapeutic diet is recommended (table No. 7, No. 10). Salt is excluded from the diet, the intake of liquid and animal protein is limited, the diet is enriched with potassium-containing products (dried fruits, vegetables). Arrange special fasting days.
With CHF, the main task is to reduce the load on the heart and normalize contractile function, in connection with which diuretics and cardiac glycosides are used. Hepatoprotectors and preventive antibiotic therapy with 3rd generation cephalosporins are recommended for hepatic hydrothorax.
Therapy of nephrotic syndrome requires the appointment of immunosuppressants, diuretics, anticoagulants, hypotensive agents, intravenous infusions of albumin. With myxedema, thyroid hormone replacement therapy is performed.
In the presence of cirrhotic ascites, laparocentesis is performed along with thoracocentesis. To normalize portal circulation, transjugular intrahepatic portosystemic bypass surgery is performed. The most radical method of treating cirrhosis is liver transplantation. If radical surgical tactics are not feasible, thoracoscopic closure of diaphragm defects and pleurodesis are resorted to. Mediastinal tumors are removed by videothoracoscopy or by an open method.
Prognosis and prevention
Hydrothorax is stopped when compensation for the underlying pathology is achieved. To do this, it is necessary to conduct a full course of inpatient treatment, subsequent compliance with all medical recommendations, rejection of bad habits. With the progression of organ failure, the prognosis is unfavorable. Prevention of hydrothorax is to prevent a critical decrease in the function of the heart, liver, kidneys, thyroid gland, regular medical examination.