Effects of brain tissue oxygen (PbtO2) guided management on patient outcomes following severe traumatic brain injury: A systematic review and meta-analysis by Hays, LMC, Udy, A, Adamides, AA, Anstey, JR, Bailey, M, Bellapart, J, Byrne, K, Cheng, A, Jamie Cooper, D, Drummond, KJ, Haenggi, M, Jakob, SM, Higgins, AM, Lewis, PM, Hunn, MK, McNamara, R, Menon, DK, Murray, L, Reddi, B, Trapani, T, Vallance, S, Young, PJ, Diaz-Arrastia, R, Shutter, L, Murray, PT, Curley, GF, Nichol, A