Evaluation of nebulised acetylcysteine and normal saline in the treatment of sputum retention following thoracotomy.

BACKGROUND The use of acetylcysteine as a mucolytic agent is controversial. In 1962 it was claimed to be "the most effective agent ... for the liquefaction of ... secretions" but was subsequently taken off the market as a respirator solution. Normal saline, on the other hand, is becoming increasingly popular. A study was undertaken to determine which solution is more effective at clearing retained secretions following thoracotomy. METHODS The study included 10 patients and was of single blind, two-way crossover design. Measurements taken before and after each treatment included sputum viscosity, difficulty of expectoration, weight of sputum expectorated, and oxygen saturation. RESULTS Following nebulisation of acetylcysteine, sputum viscosity was reduced, difficulty of expectoration was reduced, the weight of sputum expectorated was increased, and oxygen saturation was increased. There were no changes after nebulisation of normal saline. CONCLUSIONS This study shows that, following thoracotomy, nebulised acetylcysteine reduces sputum viscosity, making expectoration easier and improving oxygenation. Nebulised normal saline has no effect.