HYPOGLYCEMIA

defination

• The normal conc. Of blood glucose level in newborn infant is 2-7mmol/l(35-120mg/dl

• In healthy term infants, serum glucose values are rarely less than 35 mg/dL between 1 and 3 hr of life, less than 40 mg/dL from 3 to 24 hr, and less than 45 mg/dlafter 24 hr

• Ablood glucose concentration below 2mmol/l(35mg/dl) is defind as neonatal hypoglycemia

….cont..

• Clinically hypoglycemia may also be defined as the presence of neurologic (lethargy, coma, apnea, seizures) or sympathomimetic (pallor, palpitations, diaphoresis) manifestations that respond to glucose,

• Mild hypoglycemia defind as blood glucose conc. b/n1.5-2mmol/l(25-35mg/dl)

• Sever hypoglycemia is defind as blood glucose conc. Below1.5mmol/l(25mg/dl)

CLASSIFICATION OF HYPOGLYCEMIA IN INFANTS AND CHILDREN

1. NEONATAL TRANSIENT HYPOGLYCEMIA- Associated with Inadequate Substrate or Immature Enzyme Function in Otherwise Normal Neonates

2.Transient Neonatal Hyperinsulinism Present in: Infant of diabetic mother,Small for gestational age,Discordant twin,Birth asphyxia

…Cont…

3.NEONATAL, INFANTILE, OR CHILDHOOD PERSISTENT HYPOGLYCEMIA

hormonal disorder counter regulatory hornon def. Glycogenolysis and Gluconeogenesis Disorders Lipolysis Disorders Fatty Acid Oxidation Disorders

WHICH INFANTS HAVE AN INCREASED RISK OF HYPOGLYCAEMIA?

1.Hyperinsulinism like• Infants of mothers with diabetes mellitus or gestational

diabetes• infants with severe erythroblastosis fetalis, • insulinomas,• familial or sporadic hyperinsulinemia,• Beckwith syndrome (an inherited disease that is characterized by

macroglossia, umbilical hernia, hypoglycemia, abnormal enlargement of the viscera)

• panhypopituitarism

…Cont…

2.Increased metabolic demands: Hypoglycemia may develop in very immature or severely ill infants as a result of increased metabolic needs disproportionate to substrate stores and the calories supplied like in

• low-birthweight infants with respiratory distress syndrome• perinatal asphyxia• Polycythemia • hypothermia,• systemic infections• infants in heart failure with cyanotic congenital heart

disease, are at increased risk.

…cont…

3.IUGR/prematurity: experienced intrauterine malnutrition due to

• reduced hepatic glycogen stores and total body fat,• impaired gluconeogenesis• diminished free fatty acid oxidation• low cortisol production rates 4. Genetic causes- primary metabolic defects, such as

Galactosemia,glycogen storage disease,fructose intolerance etc.

Clinical manifastation

• Hypoglycaemia may produce NO CLINiCAL SIGNS or present with non specific signs only.

• Often an infant has some signs of brain stimul ation and other signs of brain depression at the same time ,

• This makes the clinical diagnosis of hypoglycaemia very variable difficult and unreliable.

…Cont…

• When present, the signs and symptom of hypoglycaemia are:

1. DEPRESSION OF BRAIN FUNCTION. The infant may be lethargic and hypotonic, feed poorly, have a weak cry, apnoea, cyanosis or an absent Moro reflex.

2. OVERSTIMULATION OF BRAIN FUNCTION. The infant may be jittery with a high pitched cry, a fixed stare and fisting, have abnormal eye movements or convulsions.

3. EXCESSIVE SWEATING. This sign may not be present especially in preterm infants

• cardiac arrest and failure also occur

Diagnosis of hyperglycemia

• The clinical diagnosis is difficult and often missed .Therefore, it is essential that all infants at risk of hypoglycaemia , and infants with clinical signs that may be caused by hypoglycaemia, be screened with reagent strips .

• Diagnosis of hypoglycemia by reagent strips should be confirmed with alaboratory blood glucose measurement.

Prevention of hypoglycemia

• The following steps must b e taken to prevent hypoglycaemia:

1. Identify all infants at high risk of developing hypoglycaemia.

2. Monitor the blood glucose concentration of these infants with reagent strips so that afalling blood glucose can be detected before hypoglycaemic levels are reached.

3. Feed all infants as soon as possible after delivery, espe cially preterm, underweight for gestational age and wasted infants, as well as infants of diabetic women.

…cont…

4. Whenever possible, milk feeds should b e given. Both clear feeds orally and oral dextrose feeds shouldn’t be used in newborn infants as they are low in energy and may result in hypoglycaemia .

5. If milk feeds can not be given, then an intravenous infusion of Neonatalyte should be comm enced.Neonatalyte contains 10 % glucose.

6. Prevent hypothermia.

treatment

• When symptoms other than seizures are present, an intravenous bolus of 200 mg/kg (2 mL/kg) of 10% glucose is effective in elevating the blood glucose concentration.

• In the presence of convulsions, 4 mL/kg of 10% glucose as a bolus injection is indicated

• After initial therapy, a glucose infusion should be given at 8 mg/kg/min

• If hypoglycemia recurs, the infusion rate and concentration should be increased until 15-20% glucose is used

…cont…

• if the infusion is inadquat to eleminate the symptoms hyperinsulinemia is probably present and diazoxide should be administered

• If the diazoxide is unsuccessful, octreotide may be useful

• many infants with severe persistent hyperinsulinemic hypoglycemia undergo subtotal pancreatectomy

monitoring

• The serum glucose level should be measured every 2 hr after initiating therapy until several determinations are above 40 mg/dL.

• Subsequently, levels should be measured every 4-6 hr and the treatment gradually reduced and finally discontinued when the serum glucose value has been in the normal range and the baby asymptomatic for 24-48 hr.

• Treatment is usually necessary for a few days to a week, rarely for several wks

prognosis

• The prognosis is good in asymptomatic patients with hypoglycemia of short duration

• Symptomatic infants with hypoglycemia, particularly

- low-birthweight infants, -those with persistent hyperinsulinemic

hypoglycemia, - and infants of diabetic mothers, have a poorer

prognosis for subsequent normal intellectual development than asymptomatic infants do.

Fluid and electrulyte management in term and preterm newborns

introduction

• Disorders of fluid and electrolyte balance are among the commonest derangements encountered in preterm and critically sick neonates

• The aim of fluid and electrolyte therapy is to ensure a smooth transition from the aquatic in-utero environment to the dry ex- utero environment

Changes in body water and solute after parturition

• After birth, there is efflux of fluid from the intracellular fluid (ICF) to the extracellular fluid (ECF) compartment.

• This increase in the ECF compartment floods the neonatal kidneys eventually resulting in a salt and water diuresis by 48-72 hours.

• Loss of this excess ECW results in physiological weight loss in the first week of life.

…cont…

• Since the ECW compartment is larger in more preterm neonates, the weight loss is greater in preterm neonates.

• Failure to loose this ECF may be associated with morbidities like patent ductus arteriosus (PDA), necrotizing enterocolitis (NEC) and chronic lung disease (CLD) in preterm neonates

Renal function

• Kidneys in the neonate have a limited capacity to excrete both concentrated and dilute urine

• the neonatal kidney has a limited capacity both to excrete and to conserve sodium.

• Therefore, sodium supplementation should be started after ensuring initial diuresis(48-72hrs)

…cont…

• Sodium requirement ranges from 3-5 mEq/kg/day in preterm neonates after the first week of life.

• Failure to provide this amount of sodium may be associated with poor weight gain

• Very low birth weight infants on exclusive breast feeding may need sodium supplementation in addition to breast milk until 32-34 weeks corrected age

Fluid losses

1.sensible loss-kidneys and gastro-intestinal system 2.Insensible loss-evaporation from the skin(70%) and

respiratory tract(30%). • The emphasis in fluid and electrolyte therapy

should be on prevention of excessive IWL rather than replacement of increased IWL

Managment

Management of fluid in newborn depends on gestational age and birth weight

1.Day 1: Term babies and babies with birth weight > 1500 grams. total fluid therapy would be 60 ml/kg/day of 10% dextrose

2.Day 1: Preterm baby with birth weight 1000-1500 grams.

…cont…

• the fluid requirement will be higher due to increased IWL and increased weight loss .

• using caps, socks and plastic barriers under the radiant warmer reduce the IWL

• Using this method we have found 80 ml/kg/day of 10% dextrose to be adequate on day 1 of life

…cont…

3. Day 2 -7: Term babies and babies with birth weight >1500 grams.

• As the infant grows and receives enteral milk feeds, the solute load presented to the kidneys increases and the infant requires more fluid to excrete the solute load.

• Water is also required for fecal losses and for growth purposes.

…cont…

• The fluid requirements increase by 15-20 ml/kg/day until a maximum of 150 ml/kg/day

• Sodium and potassium should be added after 48 h of age and glucose infusion should be maintained at 4-6 mg/kg/min

…cont…

4.Day 2 –7: Preterm babies with birth weight 1000-1500 grams

• As the skin matures in a preterm baby, the IWL progressively decreases and becomes similar to aterm baby by the end of the first week.

• Plastic barriers, caps and socks are used throughout the first week in order to reduce IWL from the immature skin.

…cont…

• Fluids need to be increased at 10-15 ml/kg/day until a maximum of 150 ml/kg/day.

• Sodium and potassium should be added after 48 hours and glucose infusion should be maintained at 4-6 mg/kg/min

5.>Day 7: Term babies and babies with birth weight >1500 grams Fluids should be given at 150-160 ml/kg/day

…cont…

6.Day 7: Preterm babies with birth weight 1000-1500 grams Fluids should be given at 150-160 ml/kg/day

• and sodium supplementation at 3-5 mEq/kg should continue till 32-34 weeks corrected gestational age

Monitoring of fluid and electrolyte status

1.Body weight2.Clinical examination-for any sign of dehydration.• Infants with 10% (100 ml/kg) dehydration may have

sunken eyes and fontanel, cold and clammy skin, poor skin turgor and oliguria

• Infants with 15% (150ml/kg) or more dehydration would have signs of shock (hypotension, tachycardia and weak pulses)

…cont…

3.Serum biochemistry:4.Urine output, specific gravity (SG) and osmolarity:5.Serum blood urea nitrogen (BUN), creatinine

starting electrolytes in fluid therapy

• Sodium and potassium should be started in the IV fluids after 48 hours, each in a dose of 2-3 meq/kg/day.

• Calcium may be used in a dose of 4 ml/kg/day (40 mg/kg/day) of calcium gluconate for the first 3 days in certain high-risk situations

Referance

1. Nelson Textbook of Pediatrics (19th Edition)2. Fluid and electrolyte management in term

and preterm neonates(AIIMS- NICU protocols 2008)

3.Internat