Scottish multicentre trial of glutamine and selenium supplemented parenteral nutrition for critically ill patients (SIGNET trial)

Intensive care unit (ICU) and subsequent hospital mortality are high, and infections in ICU are associated with a two-three times increased risk of death. Systematic reviews suggest that supplementing parenteral nutrition (PN) in critical illness with glutamine or selenium may reduce infections and mortality. Three different strategies were evaluated in this randomised controlled trial: glutamine supplement, selenium supplement, and both glutamine and selenium supplements. A pilot study with 20 participants evaluated recruitment procedures, data collection procedures and delivery of trial materials. 500 patients were recruited to the main trial. The primary outcomes were length of stay, mortality and episodes of sepsis. Secondary outcomes included antibiotic usage, quality of life and cost-effectiveness. Data collection was facilitated by the involvement of the Scottish Intensive Care Society (SICS) audit.

Outcome and Translation

It is anticipated that both glutamine and selenium have the potential to influence the immune system, through different sites in biochemical pathways. However, there is a danger that glutamine and selenium solutions will be incorporated into practice without adequate evaluation. The study results provided decision makers and practitioners with the clinical and cost effectiveness evidence they need to determine whether glutamine and selenium solutions can be incorporated into practice.

HERU researchers involved in this research project: Luke Vale (HERU/HSRU)

External Collaborators: A Milne, G McPherson, J Norrie, A Avenell, M Campbell, D Jenkinson (HSRU, University of Aberdeen); P Andrews, C Battison (University of Edinburgh); B Croal, W Simpson (NHS Grampian); F MacKirdy (Scottish Intensive Care Society) and D Noble (Dept of Medicine and Therapeutics, University of Aberdeen)

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Andrews, P., Avenell, A., Noble, D., Campbell, M., Battison, C., Croal, B., Simpson, W., Norrie, J., Vale, L., Cook, J., de Verteuil, R. and Milne, A. (2007) 'Randomised trial of glutamine and selenium supplemented parenteral nutrition for critically ill patients', Protocol Version 9, 19 February 2007, Known as SIGNET (Scottish Intensive care Glutamine or seleNium Evaluative Trial) Trials, 8, 25.