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Diabetic Ketoacidosis Irene N. Sills, MD Albany Medical Center Albany, NY. Diabetic Ketoacidosis Presentation of new onset diabetes about 30% of the time Is a life-threatening emergency The metabolic abnormalities must be corrected in a careful, vigilant fashion. Diabetic Ketoacidosis.
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Diabetic Ketoacidosis Irene N. Sills, MD Albany Medical Center Albany, NY
Diabetic Ketoacidosis Presentation of new onset diabetes about 30% of the time Is a life-threatening emergency The metabolic abnormalities must be corrected in a careful, vigilant fashion
Diabetic Ketoacidosis • Pathophysiology • Diagnosis • Treatment • Complications of treatment • When the acidosis is resolved
Diabetic Ketoacidosis • Abnormal metabolic state • Due to insulin deficiency • In patient with type 1 diabetes • Characterized by hyperglycemia and acidosis
Hyperglycemia Ketone production Ketone utilization Osmotic diuresis HYPERKETONEMIA DEHYDRATION vomiting Decreased GFR Hydrogen ion production exceeds utilization ACIDOSIS
Endogenous Compensation for Acidosis • Chemical buffering by extracellular (bicarbonate) and intracellular buffers (protein, organic and inorganic phosphates, hemoglobin) • Control of CO2 levels by alveolar ventilation rate • Control of blood bicarbonate concentration by changes in H+ excretion (excretion of titrable acidity and ammonium) and reabsorption of bicarbonate
Failure to take insulin (total insulin deficiency) Relative insulin deficiency infection trauma surgery stress dehydration ** Hormones that lower glucose: INSULIN Hormones that raise glucose: catecholamines, cortisol, glucagon, growth hormone Diabetic Ketoacidosis
Physical Exam • Signs of dehydration • Kussmaul type breathing • Acetone odor • Blood pressure and pulse • Temperature • Ileus and gastric atony • State of consciousness
Laboratory 1 • Glucose 400-500 mg/dl, but may vary • Arterial pH less than 7.3; bicarbonate less than 15mM/L • Sodium usually normal, but may be low • Potassium initially elevated • Serum ketones positive • Serum osmolality elevated
Laboratory 2 • Anion gap elevated: Na- (Cl + HCO3) • Creatinine spuriously elevated • Hemoglobin and hematocrit elevated • WBC may be elevated
Therapy • 1. Correction of the dehydration (PRIORITY) • 2. Correction of the hyperglycemia
Dehydration • Immediately decreases levels of “anti-insulin” hormones • Insulin resistance exacerbates the insulin deficiency • Rehydration will decrease stress hormones • Rehydration will improve kidney perfusion
Dehydration • DKA is a hypertonic state and should be corrected over 36-48 hours • If clinically in shock, 10-20 cc/kg .9NS or plasma expander over 30-45 minutes • Fluids should be no more hypotonic than .45 NS • Maintenance fluid may be .9NS until serum glucose is less than 300 mg/dl when glucose containing solution is added
Dehydration • Deficit replacement should be given EVENLY over 36-48 hours • IV infusion rate usually calculates to one and a-half times maintenance • On-going losses should be replaced • Potassium should be added when patient voids • Bicarbonate is usually not needed
Insulin • Regular (novolog) insulin U100 • 0.05 - .1U/kg/hr • If glucose is <120-180 mg/dl and acidosis is persisting, it is better to increase the glucose in the infusion rather than decrease the insulin
Monitoring • Serum glucose hourly • Electrolytes, calcium, phosphorous every 2-4 hours • Flowsheet with accurate I’s and O’s, vital signs, insulin doses, mental status checks, and laboratory results
Complications of therapy • Hypokalemia • Inadequate rehydration • Hypoglycemia • Cerebral edema and other CNS catastrophes
Hypokalemia • Vomiting • Renal losses exacerbated by hyperaldosteronism • Insulin and pH correction moves potassium into the cells • Danger if the initial potassium is less than 3.6 meq/L
Cerebral edema • Paradoxical development of CSF and CNS acidosis • Altered CNS oxygenation • Unfavorable osmotic gradients • A decline in the true sodium
Cerebral Edema • Develops 4-12 hours after therapy begun • Biochemically all is well • If early mental status changes are not noticed, a child will develop neurologic changes leading to herniation and compromised cardiorespiratory status
Cerebral Edema • NEJM: Cerebral edema that was not clinically expected developed in a small group of children • CT scans while in DKA and after resolution • Ventricular narrowing during therapy • Perhaps, some degree of swelling in all children
Cerebral EdemaPrevention • Slow rehydration with slow changes in osmolality • Serum sodium should rise as serum glucose falls • Hourly mental status checks
After Resolution IV insulin until it is time for meal Twice daily short acting/intermediate acting insulin (or usual insulin dose) Approximately .75 units/kg 2/3’s in am; 1/3 in pm 2/3’s intermediate acting; 1/3 short acting Lunch: .2 units/kg short acting
Team Management • Physician • Certified diabetes educator • Dietician • Psychologist or social worker
Insulin • Rapid acting - Humalog or Novolog • Short acting - Regular • Intermediate acting - NPH, Lente • Long acting - Ultralente • New, peakless - Glargine (Lantus)
Prebreakfast Prelunch and dinner Prebedtime snack Younger child 70 - 120 mg/dl 70 - 150 mg/dl 90 - 180 mg/dl 80 - 180 mg/dl Target Blood Glucose Levels
Principles of Meal Planning • Meet nutritional requirements • Well balanced meals and • snacks • Healthful fat consumption • Avoid obesity • Incorporate social and cultural factors • Artificial sweeteners
Carbohydrate Protein Fat 50-60% calories 15-20% calories 25-35% calories Constituents of Meal Plan
Monitoring • Hemoglobin A1c • Home glucose monitoring • Glucowatch • Subcutaneous sensor