The use of medical early warning scores in high-risk acute coronary syndrome patients in a district hospital setting

Introduction

Clinical deterioration is often preceded by a change in physiological parameters. Inappropriate action to these changes can lead to increased mortality. One way to identify the critically ill patient is through physiologically based early warning scores (EWS) [1, 2]. Use of EWS scores is advocated by the Royal College of Physicians, the Intensive Care Society and the Department of Health. Several generic scoring systems are available, although specific cardiac scoring systems also exist. The TIMI risk score for patients with unstable angina and non-ST elevation myocardial infarction (UA/NSTEMI), validated in several large patient cohorts, is broadly applicable, easily calculated and stratifies a patient's risk of future events [3].

Aims and methods

To assess the incidence of SIRS at the time of presentation in acute coronary syndrome (ACS) patients, and to assess the use of medical EWS (modified EWS [MEWS] [1], patient at-risk score [PARS] [2]) in high-risk ACS patients in a district hospital setting to determine whether they correlate with the validated TIMI UA/NSTEMI score. Over a 6-month period all patients diagnosed with NSTEMI, identified via the hospital coding system, were identified and a retrospective review was performed.

Results

Seventy-four patients were identified (age 70.4 ± 10.8 years), of which 46/74 (62%) were male. Male patients were younger 67.3 ± 10.6 vs 75.3 ± 9.4 years (P < 0.01) with a mean TIMI score 5 vs 5.3 (P = NS). The admission route was split 49%/51% between A&E and primary care. Patients were managed by cardiologists in 40% of cases. Most patients were managed on CCU, 53/74 (71%), median age 69.3 ± 10.7 vs 73.1 ± 11 years (P = NS). Over 60% of patients had a positive smoking history and 7/74 (8%) had undergone previous revascularisation.

In 22 (30%) patients a SIRS response was noted. Patients with a SIRS response tended to have a slightly higher 12-hour troponin T measurement (1.2 vs 0.7 ng/ml, P = 0.2), TIMI score (5.32 vs 5, P = 0.15) and were older (74 vs 68.8 years, P = 0.06).

The median (range) MEWS and PARS scores were 1 (0–5) and 1 (0–8), respectively. There was no association between MEWS and TIMI scores (r = -0.1, P = 0.5), or PARS and TIMI scores (r = 0.2, P = 0.1). There was a positive association between MEWS and PARS scores (r = 0.5, P < 0.001).

Conclusion

EWS are used to identify patients at risk and to highlight the fact that a patient is critically ill. Recording a patient's physiological variables should be part of the daily ward routine. The TIMI risk score for patients with UA/NSTEMI should be used in patients with symptoms and signs suggestive of an ACS and not medical EWS.