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.34This increase in ketone formation is coupled with an inability in the Type I diabetic to useketones in body tissues (12).Presumably this occurs because blood glucose is present inadequate amounts making glucose the preferred fuel.Thus there is a situation where ketone bodyformation is high but ketone body utilization by the body is very low, causing a rapid buildup ofketones in the bloodstream.Additionally, in non-diabetic individuals there are at least two feedback loops to preventrunaway ketoacidosis from occurring.When ketones reach high concentrations in thebloodstream (approximately 4-6 mmol), they stimulate a release of insulin (8,12).This increasein insulin has three major effects (24).First, it slows FFA release from the fat cell.Second, byraising the insulin/glucagon ratio, the rate of ketone body formation in the liver is decreased.Third, it increases the excretion of ketones into the urine.These three effects all serve to lowerblood ketone body concentration.In addition to stimulating insulin release, ketones appear to have an impact directly on thefat cell, slowing FFA release (12,22).This would serve to limit FFA availability to the liver,slowing ketone body formation.Ultimately these two feedback loops prevent the non-diabeticindividual from overproducing ketones since high ketone levels decrease ketone body formation.Type I diabetics lack both of these feedback loops.Their inability to release insulin fromthe pancreas prevents high ketone body levels from regulating their own production.The clinicaltreatment for DKA is insulin injection which rapidly shuts down ketone body formation in theliver, slows FFA release from fat cells, and pushes ketones out of the bloodstream (12).Additionally, rehydration and electrolyte supplementation is necessary to correct for the effectsof DKA (12).The feedback loops present in a non-insulin using individual will prevent metabolic ketosisfrom ever reaching the levels of runaway DKA (12).Table 2 compares the major differencesbetween a normal diet, dietary ketosis and diabetic ketoacidosis.Table 2: Comparison of Dietary Ketosis and Diabetic Ketoacidosis (DKA)Normal diet Dietary ketosis DKABlood glucose (mg/dl) 80-120 ~ 65-80 300+Insulin Moderate Low AbsentGlucagon Low High HighKetones production (g/day) Low 115-180 400Ketone concentrations (mmol/dl) 0.1 4-10 20+Blood pH 7.4 7.4 [ Pobierz całość w formacie PDF ]