Cough threshold in people with spinal cord injuries

Background and Purpose. The purpose of this study was to compare the cough threshold between people with and without spinal cord injury (SCI). The effect of smoking on cough threshold was also investigated. Subjects. The participants were 26 people with SCI (15 smokers, II nonsmokers) and 18 people without SCT (9 smokers, 9 nonsmokers). Methods. Aerosols of citric acid were delivered with incremental doubling concentration from 62.5 mmol to 2 mel. Cough threshold was defined as the first concentration of citric acid that induced at least 2 coughs, which is associated with large chest excursion and concurrently acoustic response. Results. The mean cough thresholds of smokers and nonsmokers with SCI (209 and 417 mmol, respectively) were lower than those of smokers and nonsmokers without SCT (467 and 1,072 mmol, respectively). The mean citric acid cough thresholds decreased in smokers with and without SCI when compared with nonsmokers with and without SCI. Conclusion and Discussion. The cough sensitivity increased in subjects with SCI, and smelting could also increase the cough sensitivity. Training about the frequency and technique of cough in patients with SCI should be carefully monitored.