Pediatric Critical Care, Glycemic Control, and Hypoglycemia:  What Is the Real Target?

A common feature of critical illness is perturbed homeostasis. Thus, a central dogma of critical care has been the belief that normalizing any physiologic perturbation will promote recovery. This belief underpins the strategy of setting physiologic goals and initiating “goal-directed therapy.” One of the most debated strategies in the last decade is tight glycemic control (TGC). Faced with the common occurrence of hyperglycemia in many critical illnesses, researchers and clinicians have asked by how much, and with what effort, should blood glucose levels be reduced or “normalized”? The question is pertinent because any attempt to reduce an elevated blood glucose level might overcorrect, inducing hypoglycemia with potentially devastating consequences. Therefore, should clinicians target “normal” (80-100 mg/dL) ranges, modestly elevated ranges (eg, 140-180 mg/dL or 180-200 mg/dL), or simply avoid high levels (eg, >216 mg/dL)? Is it the range that is important, or is it limiting variability and the allostatic load that is required?