Hypoglycemia Patients and Transport by EMS in Alameda County, 2013-15.

OBJECTIVE: To estimate the rate, characteristics, and dispositions of hypoglycemia events among persons who received care from Alameda County, California, Emergency Medical Services (EMS).

METHODS: This study was based on data for 601,077 Alameda County EMS encounters during 2013-15. Subjects were defined as having hypoglycemia if EMS personnel recorded a primary impression of hypoglycemia or low blood glucose (<60 mg/dl or "unspecified low"). The outcome of interest was patient transport or non-transport to an emergency department or other care setting; we excluded 33,177 (6%) encounters which lacked clear disposition outcomes.

RESULTS: Among 567,900 eligible encounters, 8,332 (1.47%) were attributed to hypoglycemia, of which 1,125 (13.5%) were not transported. Non-transport was more likely among males, adult patients age <60, initial blood glucose >60 mg/dl or EMS arrival time 18:00-6:00.

CONCLUSIONS: Without an understanding of EMS encounters and non-transport rates, surveillance based solely on emergency department and hospital data will significantly underestimate rates of severe hypoglycemia. Additionally, given that hypoglycemia is often safely and effectively treated by non-physicians, EMS protocols should provide guidance for non-transport of hypoglycemic patients whose blood glucose levels have normalized.