[1] Inst Child Hlth, Portex Unit, UCL Ctr Altitude Space & Extreme Environm Med, London, England
[2] Univ Southampton, Univ Hosp Southampton NHS Fdn Trust, Integrat Physiol & Crit Illness Grp, Clin & Expt Sci,Sir Henry Wellcome Labs,Fac Med, Southampton, Hants, England
[3] Univ Hosp Southampton NHS Fdn Trust, Anaesthesia & Crit Care Res Unit, Mailpoint 24,CE93,E Level,Ctr Block,Tremona Rd, Southampton SO16 6YD, Hants, England
[4] NIHR Southampton Resp Biomed Res Unit, Southampton, Hants, England