Hypoglycemia

1、 HypoglycemiaVandana Nayal, MDEdited May 20051 DefinitionPlasma glucose less than 40 mg/dlImmediate questions 1. Has a plasma blood sugar been sent to the laboratory? 2. Is the baby symptomatic? 3. Is the mother a diabetic? 4. How much glucose is the infant receiving? 2 Measurement of glucoseBedside

2、 glucose strips can give incorrect values if the test is not done properly, if the strips used are too old, if the hematocrit is very high, or the glucose level is very lowThere is a wide variation when compared to laboratory determined plasma levelsGlucose concentration in whole blood is 10-15% low

3、er than in plasmaALWAYS confirm your measurement in the lab3 Symptoms of hypoglycemiaApnea, hypotonia, irritability, irregular respirations, poor sucking or feeding, exaggerated Moro reflex, cyanosis, tremors, eye rolling, pallor, seizures, lethargy, temperature instability and comaRarely bradycardi

4、a, tachycardia, high pitched cry, tachypnea, and vomitingSome have no symptoms despite documented hypoglycemia4 Glucose requirementHow much glucose is the infant receiving in IV fluids?Normal glucose requirement is 4-10 mg/kg/minCheck to be sure that calculations were correct5Causes of transient hyp

5、oglycemiaPerinatal stressSepsis, esp. Gram-negativeAsphyxia or HIEHypothermiaPolycythemiaShockInfant of diabetic motherDecreased glycogen storesInsufficient amount of glucose administeredMaternal meds: terbutaline, propranolol6 Infants of diabetic mothers40% of infants of diabetic mothers have docum

6、ented hypoglycemiaDiabetic mothers have fluctuating hyperglycemia that results in fetal hyperglycemiainduces pancreatic B-cell hyperplasia = hyperinsulismafter delivery, hyperinsulism persists and hypoglycemia results7Decreased glycogen storesIntrauterine growth retardation or small for gestational

7、agePremature infantsPost-mature infants8Causes of persistent hypoglycemiaHormone excess - hyperinsulismBeckwith-Wiedemann syndromeIslet cell adenomaBeta cell hyperplasia, dysplasiaNesidioblastosis9Beckwith-Wiedemann syndrome (because it is on the boards)Macroglossia, Omphalocele, macrosomia, ear cre

8、ases, mild to mod mental deficiencyLarge kidneys with renal medullary dysplasia, pancreatic hyperplasiaNeonatal polycythemia,cryptorchidism, hypoglycemia(1/2 to 1/3 of cases) which is responsive to HCHepatomegaly, hemihypertrophy, (increased malignancy) hepatoblastoma, immunodeficiencyUS and serial

9、alpha feto protein every 6 months till the patient is 6 years of age to r/o Wilmss and hepatoblastomaDuplication of 11p15.5 causes BWS. IGF-2 gene localization to 11p causes BWS10Persistent hypoglycemia - hormone deficienciesGrowth hormone deficiencyACTH unresponsivenessThyroid deficiencyEpinephrine

10、 deficiencyGlucagon deficiencyCortisol deficiencyHypoplastic pituitaryHypothalamic hormone deficienciesMidline CNS malformation11Defects in carbohydrate metabolismGlycogen storage disease type 1Fructose intoleranceGalactosemiaGlycogen sythase deficiencyFructose 1,6 diphosphatase deficiency12Defects

11、in amino acid metabolismMaple syrup urine diseasePropionic acidemiaMethylmalonic acidemiaTyrosinosis3-Hydroxy-3-methylglutaryl-CoA lyase deficiency13Defects in fatty acid metabolismMedium and long chain deficiency14Approach to hypoglycemiaHistory and physicalEvaluate infant for symptoms of hypoglyce

12、miaLook for signs of shock, sepsis, midline defects, or Beckwith-Wiedemann syndrome15Laboratory studies for transient hypoglycemiaSerum glucose level should be sent to the lab to confirm the paper strip resultCBC with differential to evaluate for sepsis and to rule out polycythemia16 Persistent Hypo

13、glycemiaInitial studies Serum glucose, insulin, cortisol, growth hormone at the time of hypoglycemic event; serum ketonesRatio of insulin to glucose is obtainedlevel of 0.3 indicates a non hyperinsulinemic cause of hypoglycemiaSerum ketones are low or absent in the presence of hyperinsulinemia17Foll

14、ow-up studies for persistent hypoglycemiaGH, Free Fatty acids, T3, T4, TSHGlucagon, uric acid, lactate, AlanineKetone levels before and 15 min after administration of glucagon- 0.3mg/kg/doseUrine collection for AA, OA, catecholamines, specific reducing sugarsSomatomedins (IGF-1, IGF-2, IGF binding p

15、roteins)Ultrasound or CT scan of the pancreas18ManagementOverall plan to maintain normoglycemia (level 45 mg/dL)Screen those at risk or those with symptoms suspicious for hypoglycemia glucose check every 1-2 hr before feeds until glucose levels are stable, then every 4 hoursDetermine why the baby is

16、 hypoglycemicobvious reasons or need further work up?19At risk?PrematureSGA, LGABW 25%)Asphyxiated infant (5 min Apgar 5)Infants of massively obese mothersInfants of diabetic mothersInfants with polycythemia, infection, microphallus/midline defects, anomalies associated with low glucose (BWS)20Asymp

17、tomatic hypoglycemiaTreatment is controversial Term infants, first 6-12 hrs, not high riskgive early feeding Level 25mg/dl is a medical emergencygive parenteral glucose - 2-3 ml/kg D10W IV over 2-3 minutesCheck glucose q 15-30 minutes until stableAlways follow your institution guidelines21Symptomati

18、c, persistent, or severe ( 25) hypoglycemiaIf chemstrip values persist 40 mg/dL or initial 45 mg/dL)Peripheral IV can take up to D13 otherwise will need central accessCheck glucose levels q 15-30 minutes until stableDocument improvement in symptoms 22GlucagonIf an intravenous line cannot be started, glucagon can be given to infants with ade