Characteristics and causes in patients presenting with convulsions in the Danish prehospital setting

Convulsing patients are one of the most common reasons for dispatch in the prehospital system. Determining the underlying cause of symptoms is paramount for both patient safety and determining the correct patient course. This study aims to describe the population of patients presenting with convulsions at first contact with an anesthesiologist-staffed mobile emergency care unit, to uncover the underlying reason for the convulsions, and to establish the outcome of the patient and correlate this to patient age.

This retrospective cohort study was conducted through a manual review of prehospital records paired with data from the Danish Civil Person Register. It investigates all patients presenting with convulsions in Odense, Denmark, from January 1, 2011, through December 31, 2020. Patients were stratified into seven age groups and had their diagnoses categorized into eight diagnostic groups. (Endocrine, Febrile convulsions, Cerebrovascular, Cardiopulmonary, Miscellaneous, Neurological, Psychiatric, and Non-specific). Patient mortality was recorded at 7, 30, and 90 days.

In total 3,388 patients were analyzed. The distribution of patients across age groups only stood out for patients aged 0-4 years, who accounted for 33% (n = 1,130) of the population. The underlying cause for convulsions varied greatly depending on patient age. The most common diagnoses were Unspecific diagnoses (38%, n = 1,289), Febrile convulsions (25%, n = 837), and Neurological diseases (20%, n = 689). The highest rate of conveyance with MECU physician escort was in patients within the age group (80 + years) with a conveyance rate of 44.1%. The lowest rate of anesthesiologist-escorted conveyance was found in patients within the age group (20-39 years) with a conveyance rate of 22.3%. Ninety-three patients died within 7 days of contact with the mobile emergency care unit. At thirty days, 147 (4.3%) had died, and the total number of deaths within 90 days was 203 (6.0%).

Patient trajectories vary greatly across age groups. Patient mortality rates following an episode of convulsions increased considerably with age. Insight in underlying causes of convulsions and their severity may help the prehospital physician determine the correct course of action for the patient, benefiting both the provider and the patient.