Reorganisation of the Basic Life Support Segment in a Physician-Led Emergency Medical Service: A Retrospective Evaluation of Operational and Clinical Characteristics

Background: Increasing demand for emergency medical services (EMS) challenges prehospital resource availability, particularly for time-critical emergencies requiring advanced life support (ALS). Although tiered BLS and ALS response models are established in many non-physician-led EMS systems, evidence regarding qualification-based dispatch stratification within physician-led EMS systems remains limited. This study evaluated the clinical and operational characteristics of an expanded BLS dispatch segment in Berlin EMS. Methods: A retrospective observational study analysed 2,132,246 EMS missions in Berlin, Germany, between 2020 and 2024. Missions were retrospectively classified according to dispatch codes included in the expanded BLS segment, designed to allocate incidents with lower expected requirements for ALS-level interventions to appropriately qualified EMS personnel. Analyses included dispatch characteristics, clinical findings from electronic patient care records, observed safety-related indicators, and ALS response intervals. Results: Overall, 28.7% of EMS missions were classified within the expanded BLS segment. Traumatic and psychiatric presentations represented the most frequent diagnostic groups. Based on predefined clinical indicators, no immediately life-threatening condition was documented in more than 95% of missions. Cardiopulmonary resuscitation occurred in 0.03% of cases, and emergency physician involvement was documented in approximately 3% of cases. Conclusions: A substantial proportion of EMS missions represented a population with predominantly lower expected prehospital treatment complexity within a qualification-based dispatch framework. Structured emergency call interrogation combined with dispatch classification and linked clinical data enabled retrospective evaluation of this approach. Further validation against independent clinical reference standards and linkage with downstream outcomes are required to determine broader applicability.