Background Coma of unknown origin is an emergency caused by a variety of
possibly life-threatening pathologies. Although lethality is high, there are
currently no generally accepted management guidelines. Methods We implemented
a new interdisciplinary standard operating procedure (SOP) for patients
presenting with non-traumatic coma of unknown origin. It includes a new in-
house triage process, a new alert call, a new composition of the clinical
response team and a new management algorithm (altogether termed “coma alarm”).
It is triggered by two simple criteria to be checked with out-of-hospital
emergency response teams before the patient arrives. A neurologist in
collaboration with an internal specialist leads the in-hospital team.
Collaboration with anaesthesiology, trauma surgery and neurosurgery is
organised along structured pathways that include standardised laboratory tests
and imaging. Patients were prospectively enrolled. We calculated response
times as well as sensitivity and false positive rates, thus proportions of
over- and undertriaged patients, as quality measures for the implementation in
the SOP. Results During 24 months after implementation, we identified 325
eligible patients. Sensitivity was 60 % initially (months 1–4), then
fluctuated between 84 and 94 % (months 5–24). Overtriage never exceeded 15 %
and undertriage could be kept low at a maximum of 11 % after a learning
period. We achieved a median door-to-CT time of 20 minutes. 85 % of patients
needed subsequent ICU treatment, 40 % of which required specialised neuro-
ICUs. Discussion Our results indicate that our new simple in-house triage
criteria may be sufficient to identify eligible patients before arrival. We
aimed at ensuring the fastest possible proceedings given high portions of
underlying time-sensitive neurological and medical pathologies while using all
available resources as purposefully as possible. Conclusions Our SOP may
provide an appropriate tool for efficient management of patients with non-
traumatic coma. Our results justify the assignment of the initial diagnostic
workup to neurologists and internal specialists in collaboration with
anaesthesiologists
