When should you test for and treat hypoglycemia in prehospital seizure patients?

OBJECTIVES: Seizure is a frequent reason for activating the Emergency Medical System (EMS). Little is known about the frequency of seizure caused by hypoglycemia, yet many EMS protocols require glucose testing prior to treatment. We hypothesized that hypoglycemia is rare among EMS seizure patients and glucose testing results in delayed administration of benzodiazepines.

METHODS: This was a retrospective study of a national ambulance service database encompassing 140 ALS capable EMS systems spanning 40 states and Washington DC. All prehospital calls from August 1, 2010 through December 31, 2012 with a primary or secondary impression of seizure that resulted in patient treatment or transport were included. Median regression with robust and cluster (EMS agency) adjusted standard errors was used to determine if time to benzodiazepine administration was significantly related to blood glucose testing.

RESULTS: Of 2,052,534 total calls, 76,584 (3.7%) were for seizure with 53,505 (69.9%) of these having a glucose measurement recorded. Hypoglycemia (blood glucose <60 mg/dL) was present in 638 (1.2%; CI: 1.1, 1.3) patients and 478 (0.9%; CI: 0.8, 1.0) were treated with a glucose product. A benzodiazepine was administered to 73 (11.4%; CI: 9.0, 13.9) of the 638 hypoglycemic patients. Treatment of seizure patients with a benzodiazepine occurred in 6,389 (8.3%; CI: 8.1, 8.5) cases and treatment with a glucose product occurred in 975 (1.3%; CI: 1.2, 1.4) cases. Multivariable median regression showed that obtaining a blood glucose measurement prior to benzodiazepine administration compared to no glucose measurement or glucose measurement after benzodiazepine administration was independently associated with a 2.1 minute (CI: 1.5, 2.8) and 5.9 minute (CI: 5.3, 6.6) delay to benzodiazepine administration by EMS, respectively.

CONCLUSIONS: Rates of hypoglycemia were very low in patients treated by EMS for seizure. Glucose testing prior to benzodiazepine administration significantly increased the median time to benzodiazepine administration. Given the importance of rapid treatment of seizure in actively seizing patients, measurement of blood glucose prior to treating a seizure with a benzodiazepine is not supported by our study. EMS seizure protocols should be revisited.