Risk Stratification in Elderly Patients in the Emergency Department

Elderly patients (>=65 years of age) constitute an increasing population in
emergency departments (EDs) in many countries. These patients are largely
different from younger patients and undoubtedly need different approaches in
acute care. Compared to younger patients, elderly patients need more time in
the ED, use more resources and are frequently misdiagnosed. Furthermore,
elderly patients show increased risks of adverse outcomes: hospital admission,
readmission after discharge, ED return visits, loss of functional status or
death. Commonly used triage systems are not validated in elderly patients. We
hypothesize that this factor contributes to a lack of recognition of patients
at risk for adverse events or death.

In order to identify elderly patients at risk, we need to learn more about
factors associated with adverse outcomes, such as the premorbid state
(comorbidity, cognitive and functional state), vital signs, disease
severity-/triage scores, clinical first impression, patients* own perception of
disease severity and laboratory results.

If we are able to identify high-risk patients in an early stage, treatment can
be adjusted, in order improve the outcome and/or well-being of the patient.

The aim of the study is to identify the risk factors that are associated with
an adverse outcome in elderly patients presenting to the ED. Second, we aim to
find ways to identify these elderly patients in an early stage (through triage
and risk stratification scores, clinical impression and laboratory results).

Primary objective: To identify risk factors that are associated with an adverse
outcome in elderly patients (>=65 years of age) who visit the
internist/gastroenterologist at the ED.

Secondary objective:
1. To evaluate the discriminating power of several triage and risk
stratification scores in elderly patients who visit the ED.
2. To evaluate the predictive value of the clinical impression (gut feeling) of
the doctor/nurse and disease perception by the patient/companion with regard to
adverse outcomes in elderly patients who visit the ED.
3. To evaluate the predictive value of laboratory tests (routine tests and
biomarkers) with regard to adverse outcomes in elderly patients who visit the
ED.

Multicenter prospective observational cohort study

For patients participating in this study, care will be almost completely as
usual. As part of this study we want to ask all patients or their family
member/companion to fill out a questionnaire. In addition, we want to take two
extra venous and one arterial blood sample for patients participating in the
study in Zuyderland M.C. Because of lack of financial recourse no extra blood
samples will be taken in patients who participate in the study in Maastricht
UMC+.

To evaluate disease perception by the patient or their family member/companion,
we ask them to fill out a short questionnaire (4 questions) in the ED. We think
that this will only be a small burden for the patient and the family
member/companion. The day after admission, we will ask the patient a few
questions concerning their functional status in order to determine two
risk-stratification scores.

Two extra blood samples of 4.5 ml each need to be taken together with routine
blood samples in the ED. This blood will be used to determine biomarkers, such
as high-sensitivity-troponin, NT-pro-BNP, pro-calcitonin and d-dimer. As the
blood will be taken at the same time as the routine venous punctures, no extra
risk or burden for the patient is to be expected.

An arterial blood gas sample (1-2 ml) will be taken from the radial artery (or
when impossible, the femoral or brachial artery) to determine the acid-base
balance and lactate. This blood gas analysis will be used to calculate the
APACHE II score. The combination of lactate measurement and the blood gas
analysis will provide us with more information on the acid-base balance than
lactate alone. Adverse events after arterial puncture could be: possibility of
a minor bleeding, which occurs rarely. Therefore, an arterial puncture is
expected to be only a minor problem and burden for the patient.