Medical Surgical Increased ICP #2

Question

The nurse is caring for a client with increased intracranial pressure (ICP). Which assessment finding would have the most priority?

Answers

  1. Tachycardia
    • Rationale:

      This answer is not correct because when ICP increases, it causes pressure on the vagus nerve, thus causing bradycardia not tachycardia. This sign is part of the Cushing’s triad which is also referred to as Cushing’s reflex. When the ICP is increased, compression of the third cranial nerve (oculomotor nerve) will result in unequal, fixed, or dilated pupils.

  2. Hypothermia
    • Rationale:

      This answer is not correct because when ICP increases, the hypothalamus initiates an ischemic response affecting temperature regulation, thus increasing temperature, not decreasing. When the ICP is increased, compression of the third cranial nerve (oculomotor nerve) will result in unequal, fixed, or dilated pupils.

  3. Unequal pupil size
    • Rationale:

      This answer is correct because when the ICP is increased, compression of the third cranial nerve (oculomotor nerve) will result in unequal, fixed, or dilated pupils. Frequent monitoring of pupillary size and response is imperative during a neurologic assessment, especially when increased ICP is occurring since it is an early sign of increased ICP.

  4. Decreasing blood pressure
    • Rationale:

      This answer is not correct because ICP increases cause increase in blood pressure not decreasing blood pressure. This is referred to as Cushing’s reflex, or Cushing’s triad. This is often a late sign of increased ICP. When the ICP is increased, compression of the third cranial nerve (oculomotor nerve) will result in unequal, fixed, or dilated pupils.

Overview

When there is an increase in ICP, pupillary response is a focal sign for assessment. Pupil size may be affected by increased pressure which affects the third cranial nerve which is one reason for frequent monitoring of pupillary size and response. The correct answer is unequal pupil size.

Explanation

Learning Outcomes

Pupillary assessment is necessary to detect changes in ICP. Normal assessment for pupils is PERRLA or “Pupils equal, round and reactive to light and accommodation”. Pupils should both be round and the same size (between 2-5 mm in diameter). Pupils should also react to light and accommodate appropriately. Tools for this assessment include a penlight, pupil scale, and a pen or the nurse’s index finger to check for accommodation. Compression of the third cranial nerve (oculomotor nerve) will result in unequal, fixed, or dilated pupils.

Test Taking Tip

It is important to understand Cushing’s triad. Remember some of Cushing’s triad signs are opposite of that of shock (increased blood pressure, decreased heart rate). Also, the third sign of the triad is widened pulse pressure (difference between systolic blood pressure and diastolic blood pressure) and some sources have the third component as irregular respirations (Cheyne-Stokes breathing).

Video Rationale