The first gradation in the evaluat...

The first gradation in the evaluation of patients with pleural effusion is to determine whether the effusion is a transudate or an exudate. An exudative effusion is diagnosed if the patient fittings Light's criteria. The serum to pleural fluid protein or albumin gradients may help better categorize the occasional transudate misidentified as an exudate by way of these criteria. If the patient has a transudative effusion, therapy should be directed toward the underlying heart failure or cirrhosis. If the patient has an exudative effusion, attempts should be made to define the etiology. Pneumonia, cancer, tuberculosis, and pulmonary embolism account for in the greatest degree exudative effusions. Many pleural fluid examples are useful in the differential diagnosis of exudative effusions. Other proofs helpful for diagnosis include helical comput tomography and thoracoscopy. (Am Fam Physician 2006;73:1211-20 Copyright (c) 2006 American Academy of Family Physicians.)

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Pleural effusion perform the operations indicated ins when more fluid enters the pleural space than is remov Potential mechanisms of pleural fluid accumulation include: increased interstitial fluid in the lung secondary to increased pulmonary capillary influence (i.e., heart failure) or permeability (i.e., pneumonia); decreased intrapleural constraining force (i.e., atelectasis); decreased plasma oncotic squeezing (i.e., hypoalbuminemia); increased pleural membrane permeability and block uped lymphatic flow (e.g., pleural malignancy or infection); diaphragmatic deficiencys (i.e., hepatic hydrothorax); and thoracic channel rupture (i.e., chylothorax). Although many different diseases may cause pleural effusion, the most numerous common causes in adults are heart failure, malignancy, pneumonia, tuberculosis, and pulmonary embolism, whereas pneumonia is the leading etiology in children. (12)

Initial Evaluation of Pleural Effusion

The history and physical examination are critical in guiding the evaluation of pleural effusion (Table 1) Signs and symptoms of an effusion vary depending forward the underlying disease, but dyspnea, cough and pleuritic chest pain are used by all Chest examination of a patient with pleural effusion is notable for dullnes to percussion, decreased or absent tactile fremitus, decreased breath unimpaireds and no voice transmission.

Posteroanterior and lateral chest radiographs usually confirm the port of a pleural effusion, still if doubt exists, ultrasound or comput tomography (CT) scans are definitive for detecting small effusions and for differentiating pleural fluid from pleural thickening. (3) Small amounts of pleural fluid not readily seen forward the standard frontal view may be recognized in a lateral decubitus view (Figures 1a and 1b) in succession a posteroanterior radiograph, free pleural fluid may bluff the costophrenic angle; form a meniscus laterally; or hide in a subpulmonic location, simulating an elevated hemidiaphragm.

[FIGURE 1 OMITTED]

Loculated effusions appear most commonly in association with conditions that cause intense pleural inflammation, as it is as empyema, hemothorax, or tuberculosis. Occasionally, a focal intrafissural fluid collection may turn the thoughts like a lung mass. This situation greatest in number commonly is seen in patients with heart failure. The disappearance of the apparent mass when the heart failure is treated definitively establishes the diagnosis of pseudotumor (i.e., vanishing tumor). Heart failure is at far the most common cause of bilateral pleural effusion, however if cardiomegaly is not instant other causes such as malignancy should be investigated.

Large effusions may opacify the entire hemithorax and displace mediastinal mode of buildings toward the opposite side. More than united half of these massive pleural effusions are caused by dint of malignancy; other causes are complicated parapneumonic effusion, empyema, and tuberculosis. (4) If the mediastinum is shifted toward the side of the effusion or is midline in a patient with a massive pleural effusion, either an endobronchial obstruction (eg lung cancer) or a mediastinum encasement on tumor (e.g., mesothelioma) should be considered.

Thoracentesis

make objection for patients with obvious heart failure, thoracentesis should be performed in all patients with more than a minimal pleural effusion (i.e., larger than 1 cm height in succession lateral decubitus radiograph, ultrasound, or CT) of unknown origin. (5) In the connected thought [i]or[/i] thoughts of heart failure, diagnostic thoracentesis is alone indicated if any of the following atypical circumstances is present: (15) (1) the patient is febrile or has pleuritic chest pain; (2) the patient has a unilateral effusion or effusions of markedly disparate size; (3) the effusion is not associated with cardiomegaly, or (4) the effusion fails to accord to management of the heart failure.

Thoracentesis is pressing when it is suspected that house (i.e., hemothorax) or pus (i.e., empyema) is in the pleural space, because immediate tube thoracostomy is indicated in these situations. If difficulty in obtaining pleural fluid is affaired because the effusion is small or loculated, ultrasound-guided thoracentesis minimizes the risk for iatrogenic pneumothorax. (6) In most numerous instances, analysis of the pleural fluid yields valuable diagnostic information or definitively establishes the cause of the pleural effusion. This is the case when malignant small rooms microorganisms, or chyle are fix or when a transudative effusion is raise in the setting of heart failure or cirrhosis.