The association between vital signs, biochemical signs of acute organ failure, and relevant clinical outcomes in emergency department patients of different age categories

Rational:
Appropriate interpretation of vital signs and biochemical signs of organ failure (assessed with blood testing) are important for recognition of early deterioration and risk stratification of emergency department (ED) patients. Risk stratification is used to decide what initial ED treatment is administered and what definitive level of care is needed (i.e. ward, medium care or intensive care unit (MCU/ICU)), affecting patient outcomes. Previous studies suggest that screening and risk stratification tools are inappropriate for older ED patients because of poor interpretation of vital signs and biochemical signs of acute organ failure, which may be caused by non-existing or inappropriate cut-off values. We hypothesize that this is caused by changing reference values for vital signs and biochemical signs of acute (i.e. hyperlactatemia) organ failure in adult ED patients with increasing age, correspondent to the paediatric patient population. To prove that cut-offs for vital signs and biochemical signs of organ failure do not exist or change with increasing age, large datasets are needed.

Objectives:
Objective 1: To assess the frequency of hospital admission, hospital length of stay (LOS), in-hospital mortality and 7-day revisits in ED patients in different age categories in whom vital signs are (not) registered.
Objective 2: To assess the association between vital signs, biochemical signs of acute organ failure and (case-mix adjusted) relevant clinical outcomes in different age categories.
Objective: 3: To assess if the presenting complaint and diagnosis (i.e. sepsis or trauma) affects the association between vital signs, biochemical signs of acute organ failure and relevant clinical outcomes in different age categories.

Study design: Retrospective multi-centre cohort study using the Netherlands Emergency department Evaluation Database (NEED).

Main study parameters/endpoints:
Hospital admission (to ward or MCU/ICU), in-hospital mortality, hospital LOS, 7-day ED revisit.

Benefits: The present study will contribute to improved recognition and age-adjusted risk stratification of ED patients. It has the potential to improve numerous guidelines used for risk stratification of ED patients as the currently used cut-off points in risk stratification tools may need adjustment. Finally it may lead to adjusted endpoints for resuscitation in the ED. However, for the ED patients already included in the database the present study will have no benefit unless they revisit our ED in the future.
Burden: Not applicable.
Risks: Not applicable.

Cut-off values for vital signs and blood values don't exist, or change with age

Discharge out of hospital or mortality in-hospital, Direct ICU admission from Emergency derpartment