Page 245 - Critical Care Nursing Demystified

230 CRITICAL CARE NURSING DeMYSTIFIED

Temperature

Increases in body temperature with neurological trauma could be evident and
resistant to antipyretic therapy. In these cases, patients might benefit from being
placed on cooling blankets to create mild hypothermia, prevent increases in
intracranial pressure, and decrease cellular metabolism.

NURSING ALERT

Remember that temperature regulation is controlled by the hypothalamus of the
brain. Any time a severe trauma like stroke/brain injury occurs, the temperature can
soar to high levels! Change in temperature increases metabolism and can lead to
further increases in intracranial pressure.

Pulse

Variations in cardiac rate and rhythm can occur from increases in intracranial
pressure leading to bradycardias and other dysrhythmias. Extreme bradycardia
can be viewed as a sign of impending death. Downloaded by [ Faculty of Nursing, Chiangmai University 5.62.158.117] at [07/18/16]. Copyright © McGraw-Hill Global Education Holdings, LLC. Not to be redistributed or modified in any way without permission.

Blood Pressure
Blood pressure is controlled by the medulla. Hypertension is most commonly
seen with a neurological injury because cerebral blood volume and blood flow
increase dramatically, resulting in an increase in intracranial pressure (ICP).
The normal ICP is 0 to 10 or 0 to 15 mm Hg. Increases of 20 mm Hg for
periods of 5 minutes or longer is life threatening. Causes of increased intracra-
nial pressure are brain disorders such as hematomas, tumors, infection, CVA,
hydrocephaly, head trauma, cerebral hemorrhage, and edema. The body
attempts to compensate for ICP by displacing CSF into the spinal canal or by
absorbing it into the venous blood system.
Classic symptoms of an increase in intracranial pressure include Cushing’s
triad or syndrome. This is a classic response to an accompanying brain lesion or
injury and is a life-threatening event. There is an increase in the systolic blood
pressure with an increased and widening pulse pressure, decreased pulse (bra-
dycardia) and respiratory rate (bradypnea), decreased levels of consciousness,
diminished reflexes, projectile vomiting, unequal pupil size and decreased
pupillary reaction to light, and respiratory changes. The patient may also assume
the posturing of decerebrate (abnormal extension) or decorticate (abnormal
flexion) as his or her condition deteriorates.