Development of WEST
South African Triage Scale (SATS) is a five-level triage (red-orange-yellow-green-blue) system, where classification of triage level is made from assessment of clinical signs, VPs and clinical judgement of emergency care staff [16]. SATS guides the staff to look for clinical signs and symptoms that directly classify the patient into one out of three categories: emergency (red), very urgent (orange), or urgent (yellow). With SATS, SATS Norway, and SATS at St. Goran Hospital in Sweden as a model, the staff at the Emergency Development Center (EDC) at Sahlgrenska University Hospital developed WEST (Fig. 1) in close co-operation with specialists representing different fields of medicine. With nominal group technique, the group agreed on how to perform risk assessment, according to clinical signs and symptoms named “warning signs and symptoms.” According to the description of the warning signs and symptoms, the patient can be directly categorized to their triage severity level or, if the chief complaint does not correspond to a specific warning sign and symptom, the patient will be prioritized according to other variables such as the VPs and the clinical judgement by the triaging staff. As in the original SATS, WEST uses a calculated score for assessment of VPs [17]. With an accumulated score of VPs deterioration is easily detected. In WEST, surveillance of VPs performed using the updated version of the National Early Warning Score (NEWS2) [18]. The score harmonizes with in-hospital care at Sahlgrenska University Hospital where NEWS2 is already implemented. One ambition with WEST was to utilize the competence of the ED care staff and thus the developers of WEST decided that the clinical judgement should be an outspoken variable in the triage system enabling the triaging team to use clinical judgement in their final prioritization [19]. The clinical judgement is an overall clinical assessment by the triaging nurse, based on how the patient looks and acts, the so-called clinical gestalt. In addition, the clinical judgement considers the patients previous health history and condition. For example, a cold and diaphoretic patient with chest pain, previous heart disease with normal ECG finding, green NEWS2 and yellow warnings sign can be upgraded to the orange (second highest) triage level. Since red and orange triage levels are indicators of high urgency, clinical judgement alone can never be used to down prioritize patients. Another potential feature of WEST is the possibility to include other elements of care, such as need for direct admission to hospital and frailty assessment in older patients [20]. Thus, WEST uses the combined assessment of warnings signs and symptoms, VPs, clinical judgement and additional needs (Fig. 1).
Design, study population, and education of test nurses
This is an observational descriptive pilot study where nurses either in the ED or in the ambulance service triaged each patient with both RETTS© and WEST. Patients, both walk-ins and arriving by ambulance at the three adult EDs (ED 1–3) of Sahlgrenska University Hospital, Gothenburg Sweden, were included in the study. Patients where the ambulance bypassed the ED and admitted patients directly for inpatient care, children < 16 years of age transported to children’s hospital and patients triaged when none of the test nurses were on duty were excluded.
Six nurses, experienced in emergency triage, from each ED site and from the ambulance service (N = 24) were trained in how to perform an assessment according to WEST by the developers at the EDC. These nurses were defined as test nurses in the study. Education of test nurses was performed in small groups at each site for 4 h on 2 separate occasions. Test nurses were scheduled day, evening, and night shifts in the EDs and ambulance services. The prioritization, according to WEST, was made on triage forms immediately after the RETTS© prioritization, with the patient still in the triage room/ambulance. Patient assessment and triage in the ambulance service was conducted at scene with both RETTS© and WEST. Any changes of patients warning signs and symptoms or VPs during transport were documented but the final assessment priority at scene was included in the study.
Data collection and statistical analysis
Calculations based on patient inflow indicated that a three-week sampling period would generate a study population of approximately 1500, which was deemed sufficient for a pilot study. No power calculation was performed. Data were continuously collected during a 3-week period (3 December–23 December 2018). Registration of WEST took only a few seconds-minutes to perform, and the instruction to the test nurses was to triage the patient as if WEST was the existing triage system. This was performed to minimize any bias by the existing triage system. The patients’ triage level during the ED visit was not changed but remained as if only the RETTS©-triage system was used.
All triage was performed using the Swedish version of the WEST flow sheet including warning signs and symptoms and a data collection chart. The flow sheet and chart are attached as additional files (Additional file 1).
All patients prioritized according to both triage systems were eligible for data analysis. Data were registered on mode of arrival, chief complaint, RETTS©-ESS-code, VPs according to RETTS© and RETTS© triage-level. Furthermore, data on WEST color/prioritization, warning signs and symptoms of WEST, NEWS2 VPs, and the final clinical judgement for WEST were registered.
In addition, we used follow-up data from the patient administrative systems (Elvis 5.3), a system that supports registration, scheduling, and logistics at the hospital. Data were collected for discharge categories (admission to ward, admission to intensive care unit (ICU), discharge to home, referral from the hospital to other units and left ED without seeing a doctor). Furthermore, we registered outcome data such as admission to the ICU within 72 h, unplanned revisit to an ED within 72 h, and deceased within 72 h. Data on deaths were requested from the National Board of Health and Welfare. Data were also collected from the patient medical records (Melior 220, Cerner Corporation, Kansas City, USA) with basic content for clinical documentations, prescription and administration of medications, referral and replies, letters, and certificates. Additional functions are x-ray and laboratory test results.
Data files were also grouped and analyzed descriptively, according to the different subgroups of triage levels. The complete dataset was de-identified.
The analysis of the data was performed by descriptive statistics. Statistical analysis of the RETTS© and WEST final triage level was performed using Excel (Microsoft, CA, USA).
