The presentational flow chart "unwell adult" of the Manchester Triage System-Curse or blessing?

Background: The presentational flow chart "unwell adult" of the Manchester Triage System (MTS) occupies a special role in this triage system, defined as the nonspecific presentation of an emergency patient. Current scientific studies show that a considerable proportion of emergency room patients present with so-called "nonspecific complaints". The aim of the present study is to investigate in detail the initial assessment of emergency patients triaged according to the presentational flow chart "unwell adult".

Methods: Monocentric, retrospective observational study.

Results: Data on 14,636 emergency department visits between March 12th and August 12th, 2019 were included. During the observation period, the presentational flow chart "unwell adult" was used 1,143 times and it was the third most frequently used presentational flow chart. Patients triaged with this flow chart often had unspecific complaints upon admission to the emergency department. Patients triaged with the "unwell adult" chart were often classified with a lower triage level. Notably, patients who died in hospital during the observation period frequently received low triage levels. The AUC for the MTS flow chart "unwell adult" and hospitalization in general for older patients (age ≥ 65 years) was 0.639 (95% CI 0.578-0.701), and 0.730 (95% CI 0.714-0.746) in patients triaged with more specific charts. The AUC for the MTS flow chart "unwell adult" and admission to ICU for older patients (age ≥65 years) was 0.631 (95% CI 0.547-0.715) and 0.807 (95% CI 0.790-0.824) for patients triaged with more specific flow charts. Comparison of the predictive ability of the MTS for in-hospital mortality in the group triaged with the presentational flow chart "unwell adult" revealed an AUC of 0.682 (95% CI 0.595-0.769) vs. 0.834 (95% CI 0.799-0.869) in the other presentational flow charts.

Conclusion: The presentational flow chart "unwell adult" is frequently used by triage nurses for initial assessment of patients. Patient characteristics assessed with the presentational flow chart "unwell adult" differ significantly from those assessed with MTS presentational flow charts for more specific symptoms. The quality of the initial assessment in terms of a well-functioning triage priority assessment tool is less accurate than the performance of the MTS described in the literature.