Endocrine Abstracts

Introduction: Failure to recognise critically ill patients delays escalation to intensive care units (ICU) and results in increased mortality. Objectively identifying the sickest patients on admission remains challenging for healthcare professionals. This study proposes a novel Metabolic Index as a marker of metabolic disturbance based on a patient’s sodium, potassium and bicarbonate. The Metabolic Index is proposed as a predictor of outcome in patients presenting to A&E. A Metabolic Index of 0.8–1.2 was defined as normal. This study aims to investigate the association between Metabolic Index value on hospital admission and transfer to ICU and subsequent mortality.

Methods: 17,346 patients were included who had received an arterial or venous blood gas test in the Accident and Emergency (A&E) departments of St Mary’s and Charing Cross hospitals between March 2017 and March 2018. Patients were assessed for subsequent transfer to ICU. 516 patients admitted to ICU were followed up to primary end-point; discharge or death.

Results: Patients transferred to ICU were significantly more likely to have had a low Metabolic Index value than a normal value on admission (OR 3.01, 95% CI 2.36–3.85, P=<0.001). Patients who died in ICU were significantly more likely to have had a low Metabolic Index value than a normal value on admission (OR 2.03, 95% CI 1.22–3.46, P=0.0075).

Discussion: This novel Metabolic Index could easily be incorporated into clinical practice and has been demonstrated to be associated with increase transfer to ICU and mortality in ICU. Further work is needed, including prospective studies to control for confounders and to assess whether serial Metabolic Index calculations are stronger predictors of outcome.

Conclusion: This study demonstrates the potential use of a novel Metabolic Index to assess metabolic disturbances and objectively predict outcome in patients on presentation to A&E.