**7. Prognostic factors**

occurs, the development of tension pneumothorax may be higher. Although the risk of

Important complications of thoracentesis include pneumothorax, bleeding, infection, and spleen or liver laceration. The amount of fluid drained during thoracentesis should be sufficient to obtain a diagnosis, relieve symptoms of dyspnea, and to avoid re-expansion pulmonary oedema or pneumothorax. The general belief and the guidelines proposed removal of more than 1500 ml in one hemithorax during a single transaction. However, this random number does not consider each patient's height and weight. As a general rule, the amount of fluid discharged from thoracentesis is 20 ml per kilogram of body weight [78]. On the other hand in recent studies, the risk of re-expansion pulmonary oedema was shown to be unrelated to the amount of drained fluid and it has been suggested that no upper limit is required [79]. Diagnostic thoracentesis is also useful in determining a patient's respiratory complaints that can be connected with effusion: Improvement in the patient's symptoms after thoracentesis indicates that the patient can take advantage of more invasive procedures and improve the quality of life. Persistence of respiratory symptoms in patients after thoracentesis, other causes should be investigated and before proceeding, more invasive diagnostic options should be

The use of ultrasound guidance is preferred in thoracentesis. Ultrasound guidance, at the time of determining the location of the pleural fluids reduces accidental injury, and this technique

Thoracoscopy should only be done in patients not diagnosed by less invasive procedures. Actual thoracoscopic techniques include video-assisted thoracoscopic surgery (VATS) [81] and medical thoracoscopy with either a rigid thoracoscope [82] or a semirigid pleuroscope [83, 84]. The advantages of thoracoscopy include visually directed and selective biopsies of parietal, mediastinal, and visceral pleura, direct visualization and examination of the entire hemithorax, and simultaneous lung or lymph node biopsy if required. The procedure is well tolerated with

Medical thoracoscopy when compared with surgical thoracoscopy (which is more precisely known as video-assisted thoracic surgery (VATS) has the advantage that it can be performed under local anaesthesia or conscious sedation, in an endoscopy suite, using nondisposable rigid instruments. Physicians skilled in bronchoscopy should find the semirigid pleuroscope easy to use because it has the same light source, video equipment, and manual controls as the fiberoptic bronchoscope [83, 84].Thus, it is considerably less invasive and less expensive than VATS. As an exception: VATS that allows huge biopsy samples can be taken, is preferred to medical thoracoscopy in patients with suspected mesothelioma. For diagnosis of mesothelio‐ ma and classification of its subtype, a large pleural biopsy specimen is often necessary. Immunohistochemical staining provides essential information in the diagnostic evaluation [6]. Medical thoracoscopy is primarily a diagnostic procedure [47, 87, 88]. In cases of undiagnosed exudative effusions with a high clinical suspicion for malignancy, some clinicians may proceed directly to thoracoscopy if the facilities for medical thoracoscopy are available. The procedure

to remove the liquid used to assess the degree of lung reexpansion [80].

should be performed for diagnosis and possible talc poudrage [47].

pneumothorax rate is 10% in experienced hands, this risk increases in novices.

considered twice.

92 Principles and Practice of Cardiothoracic Surgery

less than 1% mortality [85, 86].

Despite all the recent advances in cancer treatment management, MPE is suggestive of end stage disease with poor prognosis [51]. The mean survival is 3-6 months after diagnosis of malignant pleural effusion. Whereas, this period can take up to 4-12 months depending upon the histolog‐ ical subtype of the primary tumor such as in breast cancer, Hodgkin's disease, or lymphoma [98, 99]. The International Association for the Study of Lung Cancer reclassified MPE to the M1a descriptor,recognizingitspredictionforpoorlong-termsurvivalwithanoverall5-year survival rate of 7% [100]. In addition, patients with malignant effusions, and a pH of less than 7:30 with wickedprognosis, shortermediansurvival,andpoorerresponse totetracyclinepleurodesisand have a high rate of first finding of malignant cells in fluid cytology [61, 101]

On the other hand, malignant pleural effusion significantly affects the quality of life and reduced mobility of patients with malignant disease.The main goals of treatment for pleural effusion are to decrease symptoms and improve the quality of life [11].
