Quiz 3: 50 Questions

Neurological Disorders NCLEX Practice |

Quiz #3: 50 Questions

1.1. Question

An 18-year-old client is admitted with a closed head injury sustained in a MVA. His intracranial pressure (ICP) shows an upward trend. Which intervention should the nurse perform first?

• Reposition the client to avoid neck flexion.
• Administer 1 g Mannitol IV as ordered.
• Increase the ventilator’s respiratory rate to 20

breaths/minute.

• Administer 100 mg of pentobarbital IV as ordered.

Correct Answer: A. Reposition the client to avoid neck

flexion.The nurse should first attempt nursing interventions, such as repositioning the client to avoid neck flexion, which increases venous return and lowers ICP. Elevate the head of the bed to greater than 30 degrees. Keep the neck midline to facilitate venous drainage from the head. Nursing care must pay close attention to changes in neurologic status, any change in vitals such as an increasingly erratic heart rate, development of bradycardia, accurate and equal intake and output when having diuresis, and maintenance of proper blood pressure.

oOption B: Osmotic agents can be used to create an

osmotic gradient across blood thereby drawing fluid intravascularly and decreasing cerebral edema.Mannitol was the primary agent used at doses of 0.25 to 1 g/kg body weight and is thought to exert its greatest benefit by decreasing blood viscosity and to a lesser extent by decreasing blood volume. Side effects of mannitol use are eventual osmotic diuresis and dehydration as well as renal injury if serum osmolality exceeds 320 mOsm.

oOption C: Hypercarbia lowers serum pH and can

increase cerebral blood flow contributing to rising ICP, hence hyperventilation to lower pCO2 to around 30 mm Hg can be transiently used.

oOption D: If nursing measures prove ineffective notify

the physician, who may prescribe pentobarbital.Pentobarbital is a drug within the barbiturate class that works primarily on the central nervous system.Common off-label uses are for control of intracranial pressure in patients with severe brain injuries, cerebral ischemia, and those receiving treatment for Reye syndrome.2. Question A client with a subarachnoid hemorrhage is prescribed a 1,000- mg loading dose of Dilantin IV. Which consideration is most important when administering this dose?

• Therapeutic drug levels should be maintained between

20 to 30 mg/ml.

• Rapid Dilantin administration can cause cardiac

arrhythmias.

• Dilantin should be mixed in dextrose in water before

administration.

• Dilantin should be administered through an IV catheter

in the client’s hand.

Correct Answer: B. Rapid Dilantin administration can

cause cardiac arrhythmias.Dilantin IV shouldn’t be given at a rate exceeding 50 mg/minute.Rapid administration can depress the myocardium, causing arrhythmias. The drug is slowly administered intravenously directly into a large central or peripheral vein through an IV catheter less than 20 gauge, not exceeding a rate of 50 mg/minute.

oOption A: Therapeutic drug levels range from 10 to

20 mg/ml. Phenytoin displays its primary signs of toxicity on the nervous and cardiovascular systems.Overdose on oral phenytoin mainly causes neurotoxicity, whereas cardiovascular toxicity is the main side effect of parenteral administration.

oOption C: Dilantin shouldn’t be mixed in solution for

administration. However, because it’s compatible with normal saline solution, it can be injected through an IV line containing normal saline. It requires dilution with

sodium chloride. Crystals will form when diluted with dextrose solution.

oOption D: When given through an IV catheter hand,

Dilantin may cause purple glove syndrome. “Purple glove syndrome” is a rare side effect that can accompany the intravenous administration of phenytoin. The worsening limb edema and discoloration appear to result from the crystallization of phenytoin within the blood. When there are extensive skin necrosis and limb ischemia, this can lead to amputations.3. Question A client with head trauma develops a urine output of 300 ml/hr, dry skin, and dry mucous membranes. Which of the following nursing interventions is the most appropriate to perform initially?

• Evaluate urine specific gravity.
• Anticipate treatment for renal failure.
• Provide emollients to the skin to prevent breakdown.
• Slow down the IV fluids and notify the physician.

Correct Answer: A. Evaluate urine specific gravity.

Urine output of 300 ml/hr may indicate diabetes insipidus, which is a failure of the pituitary to produce the antidiuretic hormone.This may occur with increased intracranial pressure and head trauma; the nurse evaluates for low urine specific gravity, increased serum osmolarity, and dehydration.

oOption B: There’s no evidence that the client is

experiencing renal failure. The most common findings in patients with diabetes insipidus are polydipsia, polyuria, and nocturia. Additional symptoms in patients with diabetes insipidus may include weakness, lethargy, fatigue, and myalgias.

oOption C: Providing emollients to prevent skin

breakdown is important, but doesn’t need to be performed immediately. Central diabetes insipidus is diagnosed when there is evidence of plasma hyperosmolality (greater than 300 mosm/l), urine hyperosmolarity (less than 300 mosm/l or urine/plasma osmolality less than 1), with polyuria

(urinary volume greater than 4 mL/kg/hr to 5 mL/kg/hr for two consecutive hours after surgery).

oOption D: Slowing the rate of IV fluid would

contribute to dehydration when polyuria is present. In cases of nephrogenic diabetes insipidus, water deprivation suboptimally increases urine osmolality.DDAVP minimally increases urine osmolality in partial nephrogenic diabetes insipidus, with no increase in urine osmolality in complete nephrogenic diabetes insipidus.4. Question When evaluating an ABG from a client with a subdural hematoma, the nurse notes the PaCO2 is 30 mm Hg. Which of the following responses best describes this result?

• Appropriate; lowering carbon dioxide (CO2)

reduces intracranial pressure (ICP).

• Emergent; the client is poorly oxygenated.
• Normal
• Significant; the client has alveolar hypoventilation.

Incorrect

Correct Answer: A. Appropriate; lowering carbon dioxide

(CO2) reduces intracranial pressure (ICP).A normal PaCO2 value is 35 to 45 mm Hg. CO2 has vasodilating properties; therefore, lowering PaCO2 through hyperventilation will lower ICP caused by dilated cerebral vessels. A subdural hematoma forms because of an accumulation of blood under the dura mater, one of the protective layers to the brain tissue under the calvarium.

oOption B: Oxygenation is evaluated through PaO2

and oxygen saturation. The clinician must begin immediate medical management. These measures include sedation, neuromuscular blockade when appropriate, moderate hyperventilation to a Pc02 (32 to 36), adequate oxygenation to maintain Sp02 greater than 95%, head elevation, and avoidance of hyperthermia.

oOption C: Often, the bleeding is undetected initially,

discovered as a chronic subdural hematoma. When there is a sufficient accumulation of blood to occupy a