[1] Aberdeen Royal Infirm, Dept Surg, Aberdeen AB25 2ZN, Scotland
[2] Aberdeen Royal Infirm, Dept Intens Care Med, Aberdeen AB25 2ZN, Scotland
[3] Univ Aberdeen, Hlth Serv Res Unit, Aberdeen, Scotland
[4] Glasgow Royal Infirm, Acad Unit Surg, Glasgow G4 0SF, Lanark, Scotland
[5] Royal Ctr Def Med, Acad Dept Mil Surg & Trauma, Birmingham, W Midlands, England
[6] Royal London Hosp, Trauma Unit, London E1 1BB, England
[7] Queen Elizabeth Hosp, Natl Inst Hlth Res, Surg Reconstruct & Microbiol Res Ctr, Birmingham B15 2TH, W Midlands, England