[1] Univ Florida, Dept Neurosurg, Shands Hosp, Gainesville, FL 32610 USA
[2] Univ Florida, Dept Nursing & Patient Serv, Shands Hosp, Gainesville, FL 32610 USA
[3] Univ Florida, Dept Infect Prevent & Control, Shands Hosp, Gainesville, FL 32610 USA
[4] Geisinger Hlth Syst, Crit Care Med, Danville, PA USA