Advanced Trauma Life Support ATLS Student Course Manual 2018

MEDICAL THERAPIES FOR BRAIN INJURY 121
anti-platelet therapy. After obtaining the international
normalized ratio (INR), clinicians should promptly
obtain a CT of these patients when indicated. Rapid
normalization of anticoagulation is generally required
(n TABLE 6-6).
Hyperventilation
In most patients, normocarbia is preferred. Hyperventilation
acts by reducing PaCO 2
and causing
cerebral vasoconstriction. Aggressive and prolonged
hyperventilation can result in cerebral ischemia in
the already injured brain by causing severe cerebral
vasoconstriction and thus impaired cerebral perfusion.
This risk is particularly high if the PaCO 2
is
allowed to fall below 30 mm Hg (4.0 kPa). Hypercarbia
(PCO 2
> 45 mm Hg) will promote vasodilation and
increase intracranial pressure, and should therefore
be avoided.
Prophylactic hyperventilation (pCO2 < 25 mm Hg) is
not recommended (IIB).
Use hyperventilation only in moderation and
for as limited a period as possible. In general, it
is preferable to keep the PaCO2 at approximately
35 mm Hg (4.7 kPa), the low end of the normal
range (35 mm Hg to 45 mm Hg). Brief periods
of hyperventilation (PaCO2 of 25 to 30 mm Hg
[3.3 to 4.7 kPa]) may be necessary to manage
acute neurological deterioration while other
treatments are initiated. Hyperventilation will
lower ICP in a deteriorating patient with expanding
intracranial hematoma until doctors can perform
emergent craniotomy.
Mannitol
Mannitol (Osmitrol) is used to reduce elevated
ICP. The most common preparation is a 20%
solution (20 g of mannitol per 100 ml of solution).
Do not give mannitol to patients with hypotension,
because mannitol does not lower ICP in patients
with hypovolemia and is a potent osmotic diuretic.
This effect can further exacerbate hypotension and
cerebral ischemia. Acute neurological deterioration—
such as when a patient under observation
develops a dilated pupil, has hemiparesis, or loses
consciousness—is a strong indication for administering
mannitol in a euvolemic patient. In this
case, give the patient a bolus of mannitol (1 g/
kg) rapidly (over 5 minutes) and transport her or
him immediately to the CT scanner—or directly to
the operating room, if a causative surgical lesion is
already identified. If surgical services are not available,
transfer the patient for definitive care.
table 6-6 anticoagulation reversal
ANTICOAGULANT TREATMENT COMMENTS
Antiplatelets (e.g., aspirin, plavix) Platelets May need to repeat; consider desmopressin acetate
(Deamino-Delta-D-Arginine Vasopressin)
Coumadin (warfarin) FFP, Vitamin K,
prothrombin complex
concentrate (Kcentra),
Factor VIIa
Normalize INR; avoid fluid overload in elderly patients
and patients who sustained cardiac injury
Heparin Protamine sulfate Monitor PTT
Low molecular weight heparin,
e.g., Lovenox (enoxaparin)
Protamine sulfate
N/A
Direct thrombin inhibitors
dabigatran etexilate (Pradaxa)
idarucizumab (Praxbind)
May benefit from prothrombin complex concentrate
(e.g., Kcentra)
Xarelto (rivaroxaban) N/A May benefit from prothrombin complex concentrate
(e.g., Kcentra)
FFP: Fresh frozen plasma; INR: International Normalized Ratio; PTT: Partial thromboplastin time.
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