If examined
just prior to a scheduled feeding, a normal arousal response in a neonate
more than 34 weeks gestational age is usually triggered by gently shaking
the thorax, and the arousal is sustained for at least 5 to 10 minutes.
Normal neonates born between 28 and 33 weeks gestation require more vigorous
stimulation and are seldom able to sustain an arousal for longer than
5 minutes. Neonates from 25 to 27 weeks gestation require vigorous and
frequent stimulation to arouse and the arousal is very brief.
If examined while sleep, just
after a feeding a healthy fullterm neonate when asleep may require painful
stimuli to be aroused. Once aroused, they do not remain awake for long,
even if continuously stimulated. Premature neonates often go through a
similar period after gavage feeding. A history of recent feeding prior
to the examination and the transient nature of postprandial sleep distinguishes
sleep from coma in these cases.
DIFFERENTIATING
COMA FROM
DEATH
A comatose
neonate has a heartbeat and does not meet brain death criteria. Brain
death criteria in the United States has only been established for fullterm
neonates after 7 days of age (Figure 63.1).
Figure 63.1.— Brain death criteria for fullterm neonates
from 7 to 30 days of age. 1: no brain flow for 10 minutes; 2: two EEG
isoelectric 48 hours apart; 3: two neurological examinations 48 hours
apart showing no clinical evidence of cortical or brainstem functions;
4: no movements other than spinal movements for 48 hours; 5: no brainstem
activity for 48 hours; H: hours.
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