Early recognition of the deteriorating patient. Study protocol for the analysis of blood pressure change in the unwell patient

Objective: To explore the relationship between change in systolic blood pressure (ΔSBP) in hospitalised patients, and death/ICU admission, evaluating whether the 12-hour change in systolic blood pressure (ΔSBP) improves prediction of clinical deterioration beyond the predictive performance of the NEWS2. Methods: This retrospective cohort study will use data from the HAVEN-2 dataset, collected from Oxford University Hospitals NHS Foundation Trust. Univariable and multivariable logistic regression analyses will be used to assess the association between ΔSBP and the composite outcome of ICU admission or death. Subgroup analyses will be conducted for patients with hypertension and those treated for infection.Implications: Early warning scores are used routinely across clinical practice to identify patients at risk of deterioration. This study will assess whether incorporating ΔSBP into NEWS2 improves predictive performance, potentially informing future iterations of early warning systems that better reflect dynamic physiological changes.