Abstract: This research aimed to assess the evidence for benefits and risks of positive pressure mechanical valve (PPMV) intravenous access ports on central nervous system devices (CVADs) in children. PPMVs on CVADs have been promoted as preventing occlusion and the need for heparin flushing. A search for primary research to March 2010 was conducted using MEDLINE, EMBASE and CINAHL. There is sufficient evidence that some models of PPMV intravenous access ports on CVADs, when flushed with normal saline, are associated with increased bloodstream infections in children. Further research is required.