A Prospective, Randomized Controlled Trial for a Rapid Pleurodesis Protocol for the Management of Pleural Effusions

Malignant effusions are the 2nd commonest cause of exudative effusions and 75% are due to lung, breast and lymphoma primaries. It is estimated that effusions take up about 20% of pulmonologists' work. About 15% of lung cancers have effusions at presentation and 50% will develop effusions during the course of the illness.

The current standard care of a symptomatic malignant effusion is to perform medical thoracoscopy and talc poudrage pleurodesis to prevent recurrence. Reported pleurodesis success with this technique is about 78%. However, this success rate is limited by the presence of lung entrapment that prevents lung re-expansion and effective pleurodesis. Lung entrapment occurs when there is a visceral pleural tumour peel encasing the lungs or when endobronchial tumour causes lung/lobar collapse. Thoracoscopic pleurodesis also results in significant hospital length of stay as chest tubes must stay in situ until the pleural space is dry.

There is also established data on the use of outpatient tunnelled pleural catheters in malignant effusions. Besides providing effective drainage in cases with entrapped lungs, these catheters also result in spontaneous pleurodesis in 42 to 70% of cases. The attraction of the catheters is that it enables early discharge of patients who already have a terminal illness and an extremely poor prognosis (Prognosis is usually about 3-8 months depending on the primary) However, the pleural catheters do not allow biopsies to be taken from the pleura and the pleurodesis rate is both lower and slower than with talc poudrage.

This project hopes to capitalize on the strengths of both methods ie. talc poudrage via thoracoscopy and indwelling pleural catheters, to increase the success of pleurodesis and to decrease hospital stay. Indwelling catheters may improve the success data by draining effusions associated with entrapped lungs that do not usually achieve pleurodesis with talc poudrage alone. These catheters can be left in patients on a long term basis i.e. > 6 months. The attraction of the PleurxTM tunnelled catheter system is the low risk of infections, air leaks (because of a one-way valve) and slippage.4-5 This type of study involving combining both modalities has never been reported in the literature. There is no such trial registered under clinicaltrials.gov. Pilot data (<20 patients) has been previously presented at the American College of Chest Physicians Conference 2006 from Harvard University with promising results.

Current data from our thoracoscopy service in SGH (Jan 2004 to June 2007), shows that our pleurodesis success rate is 78.2%. However, complete success was achieved in 38.1%.7 This data is in keeping with the reported literature and the failures/incomplete successes are attributed to lung entrapment.3 Our data for hospital length of stay is 9.0 ± 4.0 (range 4 to 21) days.