The type of suction system did not influence the length of hospital stay of CAIM patients, nor the
mortality rate; out of 19 deaths, ten patients were suctioned by CSS and nine by OSS. Similar conclusions are also described by Siempos et al. (2008) in a meta-analysis of nine randomized controlled trials. The statistical evaluation of the incidence of VAP, mortality rate and the length of hospital stay in ventilated patients in ICU showed no benefits to the using of CSS (Siempos, Vardakas, Falagas, 2008, p. 299-306).