Role of Biomarkers in the Prediction of Serious Adverse Events after Syncope in Prehospital Assessment: A Multi-Center Observational Study

Abstract

Syncope is defined as the nontraumatic, transient loss of awareness of rapid onset, short duration and with complete spontaneous recovery, and accounts for 1%–3% of all visits to the emergency department. The objective of this study was to evaluate the predictive capacity of the National Early Warning Score 2 (NEWS2) and prehospital lactate (pLA), individually and combined, at the prehospital level to detect patients with syncope at risk of early mortality (within 48 h) in the hospital environment. A prospective, multicenter cohort study without intervention was carried out on syncope patients aged over 18 who were given advanced life support and taken to the hospital. Our study included a total of 361 cases. Early mortality affected 21 patients (5.8%). The combined score formed by the NEWS2 and the pLA (NEWS2-L) obtained an AUC of 0.948 (95% CI: 0.88–1) and an odds ratio of 86.25 (95% CI: 11.36–645.57), which is significantly higher than that obtained by the NEWS2 or pLA in isolation (p = 0.018). The NEWS2-L can help stratify the risk in patients with syncope treated in the prehospital setting, with only the standard measurement of physiological parameters and pLA.

Risk stratification tools for patients with syncope in emergency medical services and emergency departments: a scoping review

“…The systematic reviews included 3681 [15] to 24,234 patient(s) (visits) [16]. The follow-up period in studies varied from 48 h [6] to one month [31,36,40,[54][55][56]. The general information and results of individual studies are added in additional files 2-5.…”

“…The study of moderate quality did not perform well in robust and well-defined outcome measurements and did not report some estimate of variance for the main results [48]. Of the cohort studies, 21 were of good quality [6,9,[28][29][30][31][32][33][35][36][37][38][39][40][41][42][43][44][45][46][47], one of moderate quality [27], and one of poor quality [34]. The research question was partially described in eight studies [29,31,33,34,37,40,41,46].…”

“…The research question was partially described in eight studies [29,31,33,34,37,40,41,46]. The description of subject characteristics was deemed partially sufficient in 15 studies [6,9,27,28,30,32,33,35,36,38,40,[42][43][44][45] and insufficient in one study [34]. The sample size was inappropriate in four studies [27,34,37,40].…”

“…There were two main approaches for the application and the clinical decision regarding the different tools. A score was awarded to each element in the first approach (n = 9) [6,32,35,42,45,52,61,64,65]. These scores ranged from minus two to four, except for the point-of-care lactate test (pLA) of NEWS2-L. Of the pLA, the specific value given by the test was used [6].…”

“…Transient loss of consciousness (T-LOC) is one of the most common symptoms of patients seeking prehospital emergency medical care and constitutes a major challenge for risk stratification in (prehospital) emergency care. Patients with a T-LOC account for up to 10% of emergency medical services (EMS) emergency calls, within non-conveyance rates up to 16.7%, and makeup to 3% of all emergency department (ED) visits [1][2][3][4][5][6]. The two main groups of T-LOC are T-LOC due to head trauma and 'non-traumatic' T-LOC.…”