Is the time of calling helpful for differentiating transient ischaemic attack and stroke from mimics in primary care out-of-hours services? A cross-sectional study.

OBJECTIVES: Telephone triage of patients suspected of transient ischaemic attack (TIA) or stroke is challenging. Both TIA and stroke more likely occur during daytime, with a peak in the morning hours. Thus, the time of calling might be a helpful determinant during telephone triage. We assessed the time of calling in patients with stroke-like symptoms who called the out-of-hours services in primary care (OHS-PC), and evaluated whether the time of calling differed between patients with TIA or stroke compared with those with mimics. DESIGN: Cross-sectional study. SETTING: Six OHS-PC locations in the Netherlands. PARTICIPANTS: 1269 telephone triage recordings of patients calling the OHS-PC because of stroke-like symptoms. We collected information on patient characteristics, symptoms, time of calling and urgency allocation. The final diagnosis related to each triage call was based on letters from the neurologist (retrieved from the patient's general practitioner). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measures were the time of calling hourly and 4 hourly, and the risk of TIA or stroke/hour. The secondary outcome measure was the risk ratio of TIA or stroke in the morning (08:00-12:00h) versus other hours. RESULTS: Mean age was 68.6 (SD±18.5) years, 56.9% were women and 50.0% had a TIA or stroke. The risk ratio of TIA or stroke among people calling with stroke-like symptoms between 08:00-12:00h versus other hours was 1.13 (95% CI 1.00 to 1.28, p=0.070). After correction for age and sex, the adjusted risk ratio was 0.94 (95% CI 0.80 to 1.10, p=0.434). CONCLUSION: In patients who called the OHS-PC because of stroke-like symptoms, the time of calling did not differ between patients with TIA or stroke and patients with mimics. TRIAL REGISTRATION NUMBER: The Netherlands National Trial Registry (NTR7331).

Accuracy of telephone triage in primary care patients with chest discomfort: a cross-sectional study.

OBJECTIVE: To assess the accuracy of semi-automatic assisted telephone triage in patients with acute chest discomfort against the diagnosis of acute coronary syndrome (ACS) or other life-threatening events (LTEs). METHODS: A cross-sectional study was performed of telephone conversations with 2023 patients with acute chest discomfort (pain, pressure, tightness or discomfort) who called out-of-hours services for primary care (OHS-PC) between 2014 and 2016. Sensitivity, specificity, positive and negative predicted values were calculated for a high urgency (patient seen within one hour) against the diagnoses of ACS and other LTEs. Diagnoses were retrieved from the patients' medical records in general practice, including hospital specialists' discharge letters. RESULTS: Of 2023 patients who called because of chest discomfort, 227 (11.2%) had an ACS (men 14.9%, women 8.2%) and 58 (2.9%) had another LTE (men 3.6%, women 2.3%). The sensitivity and specificity of a high Netherlands Triage System (NTS) urgency allocation against ACS/other LTEs were 0.73 (95% CI 0.68 to 0.78) and 0.43 (95% CI 0.40 to 0.45), respectively. In 13.2% of the calls the triage nurse overruled the NTS urgency, mostly by upscaling (11.0%). The sensitivity and specificity of the final urgency allocation were 0.86 (95% CI 0.81 to 0.90) and 0.34 (95% CI 0.32 to 0.37). The positive and negative predictive values of the final urgency were 0.18 (95% CI 0.17 to 0.19) and 0.94 (95% CI 0.92 to 0.95), respectively. CONCLUSIONS: The semi-automatic triage NTS tool underestimated the urgency in 27% of patients with ACS/other LTEs. Overruling by triage nurses improved safety, but still 14% of men and women with ACS/other LTEs received too low urgency, while efficiency remained poor. TRIAL REGISTRATION NUMBER: NTR7331.

Optimisation of telephone triage of callers with symptoms suggestive of acute cardiovascular disease in out-of-hours primary care: observational design of the Safety First study.

INTRODUCTION: In the Netherlands, the 'Netherlands Triage Standard' (NTS) is frequently used as digital decision support system for telephone triage at out-of-hours services in primary care (OHS-PC). The aim of the NTS is to guarantee accessible, efficient and safe care. However, there are indications that current triage is inefficient, with overestimation of urgency, notably in suspected acute cardiovascular disease. In addition, in primary care settings the NTS has only been validated against surrogate markers, and diagnostic accuracy with clinical outcomes as the reference is unknown. In the Safety First study, we address this gap in knowledge by describing, understanding and improving the diagnostic process and urgency allocation in callers with symptoms suggestive of acute cardiovascular disease, in order to improve both efficiency and safety of telephone triage in this domain. METHODS AND ANALYSIS: An observational study in which 3000 telephone triage recordings (period 2014-2016) will be analysed. Information is collected from the recordings including caller and symptom characteristics and urgency allocation. The callers' own general practitioners are contacted for the final diagnosis of each contact. We included recordings of callers with symptoms suggestive of acute coronary syndrome (ACS) or transient ischaemic attack (TIA)/stroke. With univariable and multivariable logistic regression analyses the diagnostic accuracy of caller and symptom characteristics will be analysed in terms of predictive values with urgency level, and ACS and TIA/stroke as outcomes, respectively. To further improve our understanding of the triage process at OHS-PC, we will carry out additional studies applying both quantitative and qualitative methods: (i) case-control study on serious adverse events (SAE), (ii) conversation analysis study and (iii) interview study with triage nurses. ETHICS AND DISSEMINATION: The Medical Ethics Committee Utrecht, the Netherlands endorsed this study (National Trial Register identification: NTR7331). Results will be disseminated at scientific conferences, regional educational sessions and publication in peer-reviewed journals.