Imprecise control of glucose homeostasis is a hallmark of neonatal glu
cose metabolism. A relatively wide range of glucose concentrations is
considered 'euglycemic' (2.22-6.94 mmol/l, 40-125 mg/dl) in the neonat
al period. We investigated the effects of a wide range of glucose conc
entrations on brain stem conduction time (BCT) I-V interpeak latency o
r prolonged wave V latency, Neonates were assessed by brain stem audit
ory-evoked response followed immediately by heelstick sampling to dete
rmine the blood glucose concentration. Twenty-seven appropriate for ge
stational age (AGA) term neonates (birth weight 3,245 +/- 766 g, mean
+/- SD; gestational age 39 +/- 2 weeks) were studied 3.1. +/- 3.7 days
after birth. Twenty-three AGA preterm neonates (birth weight 2,175 +/
- 477 g; gestational age 35 +/- 1 weeks) were studied 6.0 +/- 7.2 days
after birth. Brain stem conduction time wave I-V interpeak latency an
d wave V latency were determined in two trials using a Grason-Stadler
ABR screener at a 60-decibel stimulation level in the right ear. Neona
tes were studied between 33 and 40 weeks gestational age, Although the
blood glucose concentration ranged from 1,38 to 6.83 mmol/l(25-123 mg
/dl), there was no correlation between either brain stem conduction ti
me wave I-V interpeak latency or wave V latency and blood glucose conc
entration. We conclude that alterations in glucose concentration withi
n the generally accepted neonatal euglycemic range do not effect the f
unctional status of the brain stem auditory pathway. We suggest that t
he data can be interpreted to affirm that tighter clinical control of
glucose homeostasis is probably not required in the neonatal period.