Chest
Clinical InvestigationsS-Carboxymethylcysteine in the Fluidification of Sputum and Treatment of Chronic Airway Obstruction
Section snippets
Materials and Methods
Following a pilot study of inpatients,12 a two-phase inpatient and outpatient trial was organized. Those bronchitic patients in remission who did not require continued routine therapy, who attended similarly developed medical chest units at Killingbeck Hospital, Leeds Chest Clinic, Pinderfields General Hospital, and Pontefract General Infirmary, and who produced about 25 to 50 ml of nonpurulent sputum daily, were invited to take part in a clinical therapeutic trial. For admission to the trial,
Clinical Results
Some 87 patients from three medical centers in the West Riding section of Yorkshire were admitted to the two-part studies; and of these, 85 completed the phase 1 inpatient study, and 82 completed the three-month follow-up phase 2 regimen. The phase 1 records of 13 patients from one medical center were lost in transit to the organizing medical center; hence, the records of only 72 inpatients but 82 out-patients are available for analysis. These details and those of the randomized allocation of
Discussion
The diverse nature of mucolytic agents as a group is a reflection of the chemical heterogeneity of sputum. Reid13 has suggested that freshly collected purulent sputum is more viscous than mucoid, whether obtained from the same patient or from different patients with the same bronchial disease. Certainly purulent sputum is largely composed of DNA fibers, which would not be expected to respond to disulfide-splitting agents, of which S-carboxymethylcysteine is one. Denton14 has shown that the
Acknowledgments
We are grateful to Mrs. Elizabeth Collins for her assistance and advice concerning the statistical analyses employed in these studies, to the nursing and medical staff of the various chest units involved in the day-to-day management of the patients, and to the patients themselves for their constant and sustained cooperation. Our thanks are also due to Messrs. Berk Pharmaceuticals Ltd. for making the S-carboxymethylcysteine (Mucodyne) and the placebo syrup available.
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Supported in part by a grant from Messrs. Berk Pharmaceuticals Ltd., Surrey, England.