The association between vital signs and clinical outcomes in emergency department patients of different age categories

BACKGROUND

Appropriate interpretation of vital signs is essential for risk stratification in the emergency department (ED) but may change with advancing age. In several guidelines, risk scores such as the Systemic Inflammatory Response Syndrome (SIRS) and Quick Sequential Organ Failure Assessment (qSOFA) scores, commonly used in emergency medicine practice (as well as critical care) specify a single cut-off or threshold for each of the commonly measured vital signs. Although a single cut-off may be convenient, it is unknown whether a single cut-off for vital signs truly exists and if the association between vital signs and in-hospital mortality differs per age-category.

AIMS

To assess the association between initial vital signs and case-mix adjusted in-hospital mortality in different age categories.

METHODS

Observational multicentre cohort study using the Netherlands Emergency Department Evaluation Database (NEED) in which consecutive ED patients ≥18 years were included between 1 January 2017 and 12 January 2020. The association between vital signs and case-mix adjusted mortality were assessed in three age categories (18-65; 66-80; >80 years) using multivariable logistic regression. Vital signs were each divided into five to six categories, for example, systolic blood pressure (SBP) categories (≤80, 81-100, 101-120, 121-140, >140 mm Hg).

RESULTS

We included 101 416 patients of whom 2374 (2.3%) died. Adjusted ORs for mortality increased gradually with decreasing SBP and decreasing peripheral oxygen saturation (SpO₂). Diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) had quasi-U-shaped associations with mortality. Mortality did not increase for temperatures anywhere in the range between 35.5°C and 42.0°C, with a single cut-off around 35.5°C below which mortality increased. Single cut-offs were also found for MAP <70 mm Hg and respiratory rate >22/min. For all vital signs, older patients had larger increases in absolute mortality compared with younger patients.

CONCLUSION

For SBP, DBP, SpO₂ and HR, no single cut-off existed. The impact of changing vital sign categories on prognosis was larger in older patients. Our results have implications for the interpretation of vital signs in existing risk stratification tools and acute care guidelines.

Sex differences in clinical presentation and risk stratification in the Emergency Department: An observational multicenter cohort study

OBJECTIVE

The aim of this study was to investigate whether sex differences exist in disease presentations, disease severity and (case-mix adjusted) outcomes in the Emergency Department (ED).

METHODS

Observational multicenter cohort study using the Netherlands Emergency Department Evaluation Database (NEED), including patients ≥ 18 years of three Dutch EDs. Multivariable logistic regression was used to study the associations between sex and outcome measures in-hospital mortality and Intensive Care Unit/Medium Care Unit (ICU/MCU) admission in ED patients and in subgroups triage categories and presenting complaints.

RESULTS

Of 148,825 patients, 72,554 (48.8%) were females. Patient characteristics at ED presentation and diagnoses (such as pneumonia, cerebral infarction, and fractures) were comparable between sexes at ED presentation. In-hospital mortality was 2.2% in males and 1.7% in females. ICU/MCU admission was 4.7% in males and 3.1% in females. Males had higher unadjusted (OR 1.34(1.25-1.45)) and adjusted (AOR 1.34(1.24-1.46)) risks for mortality, and unadjusted (OR 1.54(1.46-1.63)) and adjusted (AOR 1.46(1.37-1.56)) risks for ICU/MCU admission. Males had higher adjusted mortality and ICU/MCU admission for all triage categories, and with almost all presenting complaints except for headache.

CONCLUSIONS

Although patient characteristics at ED presentation for both sexes are comparable, males are at higher unadjusted and adjusted risk for adverse outcomes. Males have higher risks in all triage categories and with almost all presenting complaints. Future studies should investigate reasons for higher risk in male ED patients.