Advanced Trauma Life Support ATLS Student Course Manual 2018

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CHAPTER 10 n Pediatric Trauma
blood pressure. This can mislead clinicians who are not
familiar with the subtle physiologic changes manifested
by children in hypovolemic shock. Tachycardia and
poor skin perfusion often are the only keys to early
recognition of hypovolemia and the early initiation of
appropriate fluid resuscitation. When possible, early
assessment by a surgeon is essential to the appropriate
treatment of injured children.
Although a child’s primary response to hypovolemia
is tachycardia, this sign also can be caused by pain,
fear, and psychological stress. Other more subtle
signs of blood loss in children include progressive
weakening of peripheral pulses, a narrowing of pulse
pressure to less than 20 mm Hg, skin mottling (which
substitutes for clammy skin in infants and young
children), cool extremities compared with the torso
skin, and a decrease in level of consciousness with a
dulled response to pain. A decrease in blood pressure
and other indices of inadequate organ perfusion,
such as urinary output, should be monitored closely,
but generally develop later. Changes in vital organ
function by degree of volume loss are outlined
in n TABLE 10-4.
The mean normal systolic blood pressure for children
is 90 mm Hg plus twice the child’s age in years. The
lower limit of normal systolic blood pressure in children
is 70 mm Hg plus twice the child’s age in years. The
diastolic pressure should be about two-thirds of the
systolic blood pressure. (Normal vital functions by
age group are listed in n TABLE 10-5.) Hypotension in
a child represents a state of decompensated shock
and indicates severe blood loss of greater than 45% of
the circulating blood volume. Tachycardia changing
to bradycardia often accompanies this hypotension,
and this change may occur suddenly in infants. These
physiologic changes must be treated by a rapid infusion
of both isotonic crystalloid and blood.
Pitfall
Failure to recognize and
treat shock in a child
prevention
• Recognize that tachycardia
may be the only
physiologic abnormality.
• Recognize that children
have increased physiologic
reserve.
• Recognize that normal
vital signs vary with the
age of the child.
• Carefully reassess the
patient for mottled skin
and a subtle decrease in
mentation.
table 10-4 systemic responses to blood loss in pediatric patients
SYSTEM
MILD BLOOD
VOLUME LOSS
(45%)
Cardiovascular
Increased heart rate; weak,
Markedly increased heart rate;
Tachycardia followed by
thready peripheral pulses;
weak, thready central pulses;
bradycardia; very weak or
normal systolic blood
absent peripheral pulses; low
absent central pulses; absent
pressure (80 − 90 + 2 × age in
normal systolic blood pressure
peripheral pulses; hypotension
years); normal pulse pressure
(70 − 80 + 2 × age in years);
(