Sepsis incidence, suspicion, prediction and mortality in emergency medical services: a cohort study related to the current international sepsis guideline

Abstract

Purpose: Sepsis suspicion by Emergency Medical Services (EMS) is associated with improved patient outcomes. This study assessed sepsis incidence and recognition by EMS and analyzed which of the screening tools recommended by the Surviving Sepsis Campaign best facilitates sepsis prediction.

Methods: Retrospective cohort study of claims data from health insurances (n = 221,429 EMS cases), and paramedics' and emergency physicians' EMS documentation (n = 110,419); analyzed outcomes were: sepsis incidence and case fatality compared to stroke and myocardial infarction, the extent of documentation for screening-relevant variables and sepsis suspicion, tools' intersections for screening positive in identical EMS cases and their predictive ability for an inpatient sepsis diagnosis.

Results: Incidence of sepsis (1.6%) was similar to myocardial infarction (2.6%) and stroke (2.7%); however, 30-day case fatality rate was almost threefold higher (31.7% vs. 13.4%; 11.8%). Complete vital sign documentation was achieved in 8.2% of all cases. Paramedics never, emergency physicians rarely (0.1%) documented a sepsis suspicion, respectively septic shock. NEWS2 had the highest sensitivity (73.1%; Specificity:81.6%) compared to qSOFA (23.1%; Sp:96.6%), SIRS (28.2%; Sp:94.3%) and MEWS (48.7%; Sp:88.1%). Depending on the tool, 3.7% to 19.4% of all cases screened positive; only 0.8% in all tools simultaneously.

Conclusion: Incidence and mortality underline the need for better sepsis awareness, documentation of vital signs and use of screening tools. Guidelines may omit MEWS and SIRS as recommendations for prehospital providers since they were inferior in all accuracy measures. Though no tool performed ideally, NEWS2 qualifies as the best tool to predict the highest proportion of septic patients and to rule out cases that are likely non-septic.

Keywords: Emergency medical services; Incidence; Mortality; Paramedic; Screening; Sepsis.

Fig. 1

Sample sizes for individual analyses on case level (Dataset #3: To be linkable, EMS cases had to be billed by respective health insurance company [dataset #1] and conducted by respective EMS provider [dataset #2])

Fig. 2

In-hospital and 30-day case fatality for inpatient sepsis, myocardial infarction and stroke following EMS use (Dataset #1)

Fig. 3

Schematic representation of intersections between screening tools (imputed, linked dataset #3; patient age ≥ 18 years). A Percent and in square brackets absolute number of positive screenings (consisting of true-positives and false-positives) out of n = 4503 cases (of those, n = 78 had a confirmed inpatient sepsis). B Percent and in square brackets absolute number of true-positive cases out of all patients with a confirmed inpatient sepsis (n = 78)