One study in 2001 28 compared the level of dyspnea with and without using a 5-mL NSI before ET suctioning using a crossover, quasi-experimental study design. Using the vertical visual analogue scale, patients (17 alert adults who are mechanically ventilated) were asked to rank their dyspnea level. Saline was randomly instilled before 1 of 2 suctioning. This study showed no beneficial effects of using saline. However, it demonstrated that NSI precipitated a significant increase in the level of dyspnea up to 10 minutes after suctioning in patients older than 60 years.28