Pleurodesis, pH, and Thoracoscopic Talc Poudrage

Abstract

In this issue of Chest (see page 1482), Sanchez-Armengol and Rodriguez-Panadero continue the important work of Sahn and Good, 1 Sahn SA Good Jr, JT Pleural fluid pH in malignant effusions: diagnostic, prognostic, and therapeutic implications. Ann Intern Med. 1988; 108: 345-349 Crossref PubMed Scopus (171) Google Scholar relating the pH of malignant pleural effusions to survival and to success of pleurodesis. Four things stand out from previous work: (1) The inclusion of 119 patients who underwent pleurodesis makes their series far larger than any previous series in which pH was measured. (2) Thoracoscopic talc poudrage was extraordinarily effective in pleurodesis in the high-pH group (91 percent). (3) Poudrage was even effective in 8 of 14 cases (57 percent) in which the pH was less than 7.20 (compared with only 22 percent in patients with a pH of less than 7.30 in the small series of Sahn and Good, 2 Aelony Y King R Boutin C Thoracoscopic talc poudrage pleurodesis for chronic recurrent pleural effusions. Ann Intern Med. 1991; 115: 778-782 Crossref PubMed Scopus (80) Google Scholar in which tetracycline was used) and in 11 of 22 patients (50 percent) thought to have trapped lung—a group in which pleurodesis attempts are generally considered to be contraindicated. (4) The relationship of pH to survival and successful pleurodesis appears to be on a continuum: the lower the pH, the worse the prognosis; but the drop-off in effectiveness of poudrage appeared to be at a pleural pH of less than 7.20, whereas the drop in effectiveness with tetracycline pleurodesis appears to be at less than 7.30. 2 Aelony Y King R Boutin C Thoracoscopic talc poudrage pleurodesis for chronic recurrent pleural effusions. Ann Intern Med. 1991; 115: 778-782 Crossref PubMed Scopus (80) Google Scholar