Medical intensive care unit patients with hyperglycemia: is it possible a hypoglycemic risk close to zero?

Background: In patients with diabetic or stress hyperglycemia hospitalized for acute cardiovascular disease, the occurrence of hypoglycemia increases the risk of mortality and morbidity without this being counterbalanced by a reduction in events related to a tighter glycemic control. The guidelines on this topic agree in excluding intensive treatment, but are very discordant in recommending a conventional (<180 mg/dl) or milder (<200 mg/dl) blood glucose control.

Methods: In 1256 hyperglycemic patients (mean age 74 ± 12 years) admitted to the medical intensive care unit (MICU) for acute coronary syndrome or acute heart failure, we adopted a nurse-led protocol of mild blood glucose control with subcutaneous administration of insulin, called "BBC200" (basal-bolus correction insulin regimen with glycemic target <200 mg/dl), with the aim at maintaining average blood glucose <200 mg/dl and an indication for intravenous insulin only for blood glucose >350 mg/dl. A retrospective analysis was carried out for assessing the occurrence of hypoglycemic episodes (blood glucose <70 mg/dl) and therapeutic failure (persistent hyperglycemia with values >240 mg/dl).

Results: Mean blood glucose was 261 ± 72 mg/dl on admission and 173 ± 50 mg/dl during treatment. Five patients (0.2%) required intravenous insulin infusion. There was only one case of severe hypoglycemia (≤40 mg/dl) due to an error of administration, and 2 cases of moderate hypoglycemia (41-70 mg/dl), with a total hypoglycemia rate of 0.24%. Transient therapeutic failure occurred in 27% of cases.

Conclusions: In MICU hyperglycemic patients, the simple, intuitive and economical "BBC200" protocol could lead to a hypoglycemic risk very close to zero (0.24%), with a significant reduction in hypoglycemia-related clinical events and a modest increase in persistent hyperglycemic phenomena.