Hypoglycemia in the Newborn

Case 1 A four hour infant who was born by crash LTCS at 38 weeks for non-reassuring fetal status. The mother who used cocaine and smoked 2 packs a day presented to LD with several hours of heavy vaginal bleeding. On Fetal Monitoring repetitive late decelerations with absent beat to beat variability was noted. Initial glucose was 25mg/dl.

Case 2 20 hour old infant born by NSVD at 36 1/7 weeks is noted to have a glucose of 20. Of note, mother had infrequent prenatal visits. Infant’s birthweight was 9# 0.7 oz. On PE a fractured clavicle is noted. Delivery note comments on McRoberts and suprapubic pressure. Infant is jittery on exam.

Case 3 48 hour infant born via NSVD after SROM 20 hours. (Ampicillin given 1 hour before delivery). Infant now with poor suck, mild jaundice, and temperature of 36C. Blood work reveals glucose 30.

Case 4 20 hour infant in ICN born at 32 weeks is intubated with a UA catheter. Shortly after insertion of catheter began to have poor control of glucose despite dextrose in IV.

Case 5 An hour after sending a glucose on a 30 hour jittery baby with uncomplicated pregnancy and delivery, you call the lab for results. They can not find the blood. They call back and inform you that the blood is now being run. The result reported is 32 mg/dl.

Why care about hypoglycemia? n Glucose is crucial for cerebral metabolic fuel n After birth infant must regulate their own glucose n Persistent hypoglycemia has been associated with adverse neurodevelopment, apnea, seizures

Glucose turnover n Represents the production of glucose and the utilization n Premature infant 5-6mg/kg/min n Term infant 3-5mg/kg/min n Adult 2-3mg/kg/min n Our best estimate of this is chemical glucose testing

Methods of Testing n Test strips (variable at high Hct and very low glucose levels) n Plasma glucose level (14% higher level than whole blood) n Whole blood i.e. capillary tubes (if not transported on ice will decrease by 18mg/dl/hr)

Definition of hypoglycemia Plasma glucose less than 40mg/dl within the first 72 hours of life on at least 2 evaluations.

Causes of hypoglycemia--under production of glucose n Limited glycogen due to SGA n Limited glycogen due to prematurity n Birth stress induces catecholamines and subsequent glycogen mobilization n Glycogen storage diseases n Decreased gluconeogenesis of SGA

Causes of hypoglycemia-- over utilization n Hyper-insulinism of GDM/or oral hypoglycemic exposure n Beta cell adenomas n Beckwith-Wiedemann syndrome (exopthalmos-macroglossia-gigantism) n Beta cell hyperplasia with erythroblastosis fetalis n UA catheter between T10 and L2 stimulating pancreas

Other causes n Polycythemia n Sepsis n Hypopituitism

Symptoms n Jittery n Tremor n Cyanosis n Lethargy n Respiratory Distress n Apnea n Poor feeding n Tachycardia n Temperature instability n Emesis n Seizures

Who to screen n High risk infants (see protocol) within first 1-2 hours (follow with AC glucose) n Symptomatic infants

Therapy n Glucose >20-25mg/dl feeds with 25-30cc of formula (some use glucose water) May consider one gavage feed n <20-25mg/dl IV therapy (bolus 2ml/kg of D10W then 6-8mg/kg/min glucose

Case 1 A four hour infant who was born by crash LTCS at 38 weeks for non-reassuring fetal status. The mother who used cocaine and smoked 2 packs a day presented to LD with several hours of heavy vaginal bleeding. On Fetal Monitoring repetitive late decelerations with absent beat to beat variability was noted. Initial glucose was 25mg/dl.

Case 2 20 hour old infant born by NSVD at 36 1/7 weeks is noted to have a glucose of 20. Of note, mother had infrequent prenatal visits. Infant’s birthweight was 9# 0.7 oz. On PE a fractured clavicle is noted. Delivery note comments on McRoberts and suprapubic pressure. Infant is jittery on exam.

Case 3 48 hour infant born via NSVD after SROM 20 hours. (Ampicillin given 1 hour before delivery). Infant now with poor suck, mild jaundice, and temperature of 36C. Blood work reveals glucose 30.

Case 4 20 hour infant in ICN born at 32 weeks is intubated with a UA catheter. Shortly after insertion of catheter began to have poor control of glucose despite dextrose in IV.

Case 5 An hour after sending a glucose on a 30 hour jittery baby with uncomplicated pregnancy and delivery, you call the lab for results. They can not find the blood. They call back and inform you that the blood is now being run. The result reported is 32 mg/dl.