In a neonate with asymptomatic hypoglycemia immediate Rx should include which of the following?
Ans. B 2 ml/kg 10% Dextrose (Ref. OP Ghai 7th/pg. 155, Reference : ) Neonatal Hypoglycemia: # A blood glucose value of < 40 mg/dL (plasma glucose < 45 mg/dL). # Hypoglycemia in first 18-36 hrs is usually due to transient neonatal hypoglycemia and after 36 hrs metabolic and other causes are likely. # Persistent/recurrent hypoglycemia is defined as requiring either parenteral glucose for > 7 days or high IV glucose infusion rates (>12-16 mg/kg/min). Etiopathogenesis: # High risk factors of hypoglycemia include: 1) Infants of diabetic mothers many of whom are LGA, 2) All macrosomic (LGA) infants (mothers may have occult diabetes), 3) SGA, (i.e., intrauterine stressed) infants, 4) Stressed infants (i.e., difficult delivery, low Apgar <7 at five minutes), 5) Infants of mothers on tocolytics (terbutaline, ritodrine), oral hypoglycemics or propranolol within 72 hrs before delivery, 6) Premature infants (<37 weeks gestational age), 7) Postmature infants (>42 weeks gestational age). A) Transient hypoglycemia: 1. Maternal conditions causing transient hypoglycemia: a. Intrapartum glucose given at too high a rate to the mother. b. Drug Rx (terbutaline, ritodrine, propranolol, oral hypoglycemics). c. Intrauterine growth retardation (IUGR): placental insufficiency resulting in SGA infant. d. Diabetes in pregnancy (hyperinsulinism). 2. Neonatal conditions causing transient hypoglycemia: a. Failure to adapt extrauterine life b. Birth asphyxia c. Infection/sepsis d. Hyperviscosity e. Congenital heart disease f. Erythroblastosis fetalis g. Hypothermia. h. Inadequate calories. i. Other iatrogenic causes: exchange transfusion and/or low lying umbilical artery catheter. j. Decreased glycogen stores: Associated with pre and postmature infants. B) Persistent and/or recurrent hypoglycemia: 1. Hyperinsulinism conditions which cause persistent/recurrent hypoglycemia: a. Nesidioblastosis: rare; hyperinsulinemic hypoglycemia due to beta cell hypertrophy. It is on a continuum with islet cell adenoma and usually requires subtotal or total pancreatectomy to treat, however octreotide and diazoxide are useful Rx. b. Beckwith-Wiedemann syndrome: Visceromegaly, macroglossia, hypoglycemia. 2. Endocrine deficiency conditions which cause persistent/recurrent hypoglycemia: a. Pituitary insufficiency: septo-optic dysplasia, craniofacial defects and anencephaly (Deficiency of pituitary hormones such as growth hormone and ACTH, results in hypoglycemia). b. Cortisol deficiency/adrenal failure. c. Congenital glucagon deficiency. d. Epinephrine deficiency: Extremely rare. 3. Inborn errors of metabolism conditions which cause persistent/recurrent hypoglycemia: a. Carbohydrate metabolism: Galactosemia, glycogen storage disease, fructose intolerance. b. Amino acid meta:MSUD, propionicacidemia, methylmalonic aciduria, tyrosinemia, glutaric acidemia. c. Fatty acid metabolism: Carnitine metabolism defect, Acyl-CoA dehydrogenase defect. Rx: The goal of Rx is to establish normoglycemia, usually defined as a stable glucose value above 40 or 50 mg/dl. Asymptomatic babies: # Asymptomatic infants in the 20-40 mg/dl range may have a trial of oral feeding, but if the glucose fails to normalize, an IV glucose infusion should be started. # Although dextrose 5% oral solution is occasionally used for Rx, formula has the advantage of containing fats and proteins which are metabolized slowly and provide a more sustained level of substrates for glucose production. Blood glucose should be rechecked in 30-60 minutes after feeding. Symptomatic babies: # with severe hypoglycemia (<20 mg/dl), a small IV bolus of dextrose has been shown to raise blood sugar levels safely and more quickly to adequate levels than intravenous infusion alone. # The usual bolus is 2 ml/kg of a dextrose 10% solution given intravenously followed by a glucose infusion rate of 6 to 8 mg/kg/min. The first part of the infusion, i.e., the bolus is given as a dose of ml/kg, but the second part of the infusion is given in mg/kg/min. # A simplified formula for glucose infusion rate (in mg/kg/min) is: Glucose infusion rate (GIR) = (dextrose % concentration X ml/kg/d) / 144 # So if dextrose 10% is used at 80 ml/kg/day that gives us: GIR = (10 x 80) /144 = 800 / 144 = 5.6 mg/kg/min. # A faster way to figure this out is to use one of the following formulas to achieve a glucose infusion rate of 7 mg/kg/ minute. D5W: IV rate (in ml/hr) = 8.4 X Body Wt (in kg) D10W: IV rate (in ml/hr) = 4.2 X Body Wt (in kg) # For a 3 kg newborn infant, using D5W would result in an IV rate of 25 ml/hr, which results in 600 ml/day, or 200 cc/kg/ day, which is too much. This is why D10W must be used instead. The D10W infusion rate using the above formula would still give 100 cc/kg/day. F/U and outcome: # If the plasma glucose cannot be raised by glucose infusion alone, other options include a trial of corticosteroids (hydrocortisone 5-15 mg/kg/day IV in 2-3 divided doses or prednisone 2 mg/kg/day by mouth). # If this fails, other drugs that may be used to raise the plasma glucose include human growth hormone, diazoxide, glucagon or long acting synthetic somatostatin (octreotide). # The first step in evaluating persistent/recurrent hypoglycemia is to obtain serum glucose, insulin, and ketone levels. If the ratio of insulin to glucose (I/G ratio) is >0.3, then the cause is hyperinsulinism. Ketones should be low or absent in hyperinsulinism.
100 mg/kg 10% Dextrose
2 ml/kg 10% Dextrose
2 ml/kg 25% Dextrose
4 ml/kg 25% Dextrose