Timely empirical antibiotic therapy against sepsis in a rural Norwegian ambulance service: a prospective cohort study

Background: Early diagnosis and antibiotic therapy in patients with sepsis reduce morbidity and mortality, thus pre-hospital management is likely to affect patient outcomes. Pre-hospital administration may increase the risk of unnecessary use of broad-spectrum antibiotics, but identification of an infectious focus enables more targeted antibiotic therapy. The aim of this study was to investigate how paramedics, with or without the assistance of general practitioners, can administer empiric intravenous antibiotic treatment against sepsis in a timely manner.

Methods: Cohort study of patients with suspected sepsis that received pre-hospital intravenous antibiotics and were transported to hospital. The setting was mainly rural with long average distance to hospital. Patients received targeted antibiotic treatment after an assessment based on clinical work-up supported by scoring systems. Patients were prospectively included from May 2018 to August 2022. Results are presented as median or absolute values, and chi-square tests were used to compare categorical data.

Results: We included 328 patients. Median age was 76 years (IQR 64, 83) and 48.5% of patients were female. 30-days all-cause mortality was 10.4%. In cases where a suspected infectious focus was determined, the hospital discharge papers confirmed the pre-hospital diagnosis focus in 195 cases (79.3%). The presence of a general practitioner during the pre-hospital assessment increased the rate of correctly identified infectious focus from 72.6% to 86.1% (p = 0.009). Concordance between pre-hospital identification of a tentative focus and discharge diagnosis was highest for lower respiratory tract (p = 0.02) and urinary tract infections (p = 0.03). Antibiotic treatment was initiated 44 min (median) after arrival of ambulance, and median transportation time to hospital was 69 min. Antibiotic therapy was started 76 min (median) before arrival at hospital.

Conclusions: Pre-hospital identification of infectious focus in suspected sepsis was feasible, and collaboration with primary care physicians increased level of diagnostic accuracy. This allowed initiation of intravenous focus-directed antibiotics more than one hour before arrival in hospital in a rural setting. The effect of pre-hospital therapy on timing was much stronger than in previous studies from more urban areas.