Causes of brain dysfunction in acute coma: a cohort study of 1027 patients in the emergency department

Scand J Trauma Resusc Emerg Med. 2019 Nov 7;27(1):101. doi: 10.1186/s13049-019-0669-4.

Abstract

Background: Coma of unknown etiology (CUE) is a major challenge in emergency medicine. CUE is caused by a wide variety of pathologies that require immediate and targeted treatment. However, there is little empirical data guiding rational and efficient management of CUE. We present a detailed investigation on the causes of CUE in patients presenting to the ED of a university hospital.

Methods: One thousand twenty-seven consecutive ED patients with CUE were enrolled. Applying a retrospective observational study design, we analyzed all clinical, laboratory and imaging findings resulting from a standardized emergency work-up of each patient. Following a predefined protocol, we identified main and accessory coma-explaining pathologies and related these with (i.a.) GCS and in-hospital mortality.

Results: On admission, 854 of the 1027 patients presented with persistent CUE. Their main diagnoses were classified into acute primary brain lesions (39%), primary brain pathologies without acute lesions (25%) and pathologies that affected the brain secondarily (36%). In-hospital mortality associated with persistent CUE amounted to 25%. 33% of patients with persistent CUE presented with more than one coma-explaining pathology. In 173 of the 1027 patients, CUE had already resolved on admission. However, these patients showed a spectrum of main diagnoses similar to persistent CUE and a significant in-hospital mortality of 5%.

Conclusion: The data from our cohort show that the spectrum of conditions underlying CUE is broad and may include a surprisingly high number of coincidences of multiple coma-explaining pathologies. This finding has not been reported so far. Thus, significant pathologies may be masked by initial findings and only appear at the end of the diagnostic work-up. Furthermore, even transient CUE showed a significant mortality, thus rendering GCS cutoffs for selection of high- and low-risk patients questionable. Taken together, our data advocate for a standardized diagnostic work-up that should be triggered by the emergency symptom CUE and not by any suspected diagnosis. This standardized routine should always be completed - even when initial coma-explaining diagnoses may seem evident.

Publication types

  • Observational Study

MeSH terms

  • Aged
  • Cardiovascular Diseases / epidemiology
  • Central Nervous System Diseases / epidemiology
  • Cohort Studies
  • Coma / epidemiology
  • Coma / etiology*
  • Emergency Service, Hospital
  • Female
  • Germany / epidemiology
  • Glasgow Coma Scale
  • Hospital Mortality
  • Humans
  • Lung Diseases / epidemiology
  • Male
  • Mental Disorders / epidemiology
  • Mesenteric Ischemia / epidemiology
  • Middle Aged
  • Poisoning / epidemiology
  • Retrospective Studies