Central lines and arterial lines have similar rates of colonization and infection. Although the risk of colonization of central lines plateaus after 5 days, the risk for arterial lines continues to rise in a linear fashion.
Lucet JC, Bouadma L, Zahar JR, et al. Infectious risk associated with arterial catheters compared with central venous catheters. Crit Care Med. 2010;38:1030–1035.