Chapter 44: Acute Disorders of Brain Function

Chapter 44: Acute Disorders of Brain Function

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

MULTIPLE CHOICE

1. The physiologic change most likely to lead to an increase in intracranial pressure is

ANS:  A

Cerebral edema starts a cyclic process whereby fluid collection in the brain leads to compression of vessels, which results in inadequate blood and oxygen perfusion into the cells. This results in ischemia, which triggers vasodilation, increased capillary pressure, and increased edema. An increase in intracranial pressure is not associated with hypernatremia nor caused by respiratory hyperventilation. The physiologic change most likely to lead to increased intracranial pressure is not related to sleep.

REF:   Pg. 903

2. Manifestations of acute brain ischemia (Cushing reflex) are due primarily to

ANS:  B

An extreme increase in ICP can precipitate an intense reaction by the sympathetic nervous system as it attempts to maintain cerebral perfusion through the compressed blood vessels. This has been termed an ischemic response or Cushing reflex. Manifestations of acute brain ischemia are due to sympathetic nervous system activation. The sympathetic nervous system activates to attempt to lower the intracranial pressure accompanied by acute brain ischemia. The Cushing reflex generally is viewed as a “last-ditch” effort by the brain to re-establish cerebral perfusion but is not due to loss of brainstem reflexes.

REF:   Pg. 904

3. Which group of clinical findings indicates the poorest neurologic functioning?

ANS:  C

Decorticate posturing is an abnormal flexor response of the arms and wrists, with legs and feet extended and internally rotated. This occurs as the neurologic functioning deteriorates. Normal response occurs with spontaneous eye opening, movement on command and orientation to self. Eye opening to touch is not indicative of poor neurologic functioning. A lower neurologic functioning is indicated by a patient who is able to withdraw from painful stimulus and localize the source of pain.

REF:   Pg. 908

4. Acceleration-deceleration movements of the head often result in polar injuries in which

ANS:  D

Polar injuries occur as a consequence of the brain shifting within the skull and meninges during the course of an acceleration-deceleration movement resulting in local injury at two opposite poles of the brain. Focal injuries are those that are localized to the site of impact to the skull. Diffuse injuries occur when movement of the brain causes widespread neuronal damage. An intracranial hematoma is a localized collection of blood within the cranium.

REF:   Pg. 910