Acute Intracranial Problems Notes

Question 1

3 essential volume components of the skull

Answer 1

Brain Tissue
Blood
Cerebrospinal Fluid (CSF)

Question 2

Primary Injury

Answer 2

Occurs at the initial time of injury

Question 3

Secondary Injury

Answer 3

Effects of the primary injury that can appear in a few hours to a few days.

Question 4

Intracranial Pressure (ICP)

Answer 4

Pressure of CSF fluid within the brain.

Question 5

Factors that influence ICP

Answer 5

Arterial Pressure
Venous Pressure
Intraabdominal Pressure
Posture
Temperature
Blood Gases

Question 6

Monro-Kellie Doctrine

Answer 6

The 3 components must stay in a constant volume overall.
Only affects when the skull is closed.
Brain compensates in any component if one component is displaced more than others.

Question 7

Normal ICP ranges

Answer 7

5-15 mmHg

Question 8

Cerebral Blood Flow (CBF)

Answer 8

Blood supply given to the brain in any given time period, usually 1 minute.

Question 9

Cerebral Autoregulation

Answer 9

Automatic adjustment that the brain does to maintain a constant blood flow when arterial BP changes.

Question 10

Normal MAP

Answer 10

60-100 mmHg
Most people have 70mmHg
Critical to maintain MAP when ICP is increased

Question 11

Cerebral Perfusion Pressure (CPP)

Answer 11

Pressure needed to ensure blood flow to the brain.

Question 12

Normal CPP

Answer 12

60-100 mmHg

Question 13

How to calculate MAP

Answer 13

(SBP+2(DBP))/3

Question 14

How to calculate CPP

Answer 14

CPP=MAP - ICP or

CPP= Flow x Resistance

Question 15

Factors Affecting Cerebral Blood Flow

Answer 15

CO2
O2
Hydrogen ions (H+)

Question 16

Why is it critical to maintain CBF?

Answer 16

To preserve tissue and minimize secondary injury.

Prevent brainstem compression and brain herniation.

Question 17

3 Types of Cerebral Edema:

Answer 17

Vasogenic
Cytotoxic
Interstitial

Question 18

Vasogenic Cerebral Edema

Answer 18

Most common type

Characterized by leakage of large molecules from capillaries into surrounding extracellular space.

Question 19

Cytotoxic Cerebral Edema

Answer 19

The cell membrane breaks and moves fluids and proteins into cells.

Question 20

Interstitial Cerebral Edema

Answer 20

Result of hydrocephalus (buildup of brain fluid)

Question 21

C/M on Increased ICP

Answer 21

Changes in LOC - most reliable indicator of neuro status
Cushing’s Triad - MEDICAL EMERGENCY
Compression of Cranial Nerve III - fixed unilateral dilated pupils - MEDICAL EMERGENCY
Blurred vision, diplopia, and extraocular eye movements
Compression of Cranial Nerves II, IV, and VI.
Contralateral hemiparesis or hemiplegia
Decorticate or Decerebrate posturing
Headache
Unexpected vomiting
Projectile Vomiting

Question 22

Cushing’s Triad

Answer 22

MEDICAL EMERGENCY
Systolic HTN with widening pulse pressure
Bradycardia with bounding peripheral pulses
Irregular Respirations

Question 23

Which is worse: decorticate or decerebrate

Answer 23

Decerebrate

Question 24

Why do we have to monitor for headache?

Answer 24

Headache may appear benign but that’s an early symptom of cerebral edema and increase ICP that can lead to coma and death

Question 25

2 Major Complications:

Answer 25

Cerebral Perfusion | Cerebral Herniation

Question 26

Tentorial Herniation

Answer 26

Mass lesion in the cerebrum forces brain to herniate downwards

Question 27

Uncal Herniation

Answer 27

Lateral and downward herniation

Question 28

Cingulate Herniation

Answer 28

Lateral displacement of brain tissue under falx cerebri (dura wall that separate's 2 cerebral hemispheres)

Question 29

Diagnostic Studies

Answer 29

``` CT and MRI Cerebral angiography EEG PET Transcranial Doppler Studies Infrascanner - detects life-threatening intracranial bleeding ECG Lumbar Puncture (LP) Lab Studies ```

Question 30

Why should you not perform a LP when an ICP is suspected?

Answer 30

Possible cerebral herniation can occur when the pressure is released during a LP.

Question 31

Indications for Intracranial Pressure Monitoring

Answer 31

``` Hemorrhage Stroke Tumor Infection Traumatic Brain Injury (TBI) Pts with GCS < 8 Abnormal CT or MRI scan ```

Question 32

Ventriculostomy Nursing Management

Answer 32

Gold Standard for monitoring ICP A specialized catheter is inserted into the lateral ventricle with an external transducer. Make sure the transducer is in the same level as foramen of Monro Document ICP every hour Turn and reposition the patient every 2 hours. Check capillary blood glucose level every 6 hours. Monitor cerebrospinal fluid color and volume hourly.

Question 33

Fiberoptic Catheter

Answer 33

A sensory transducer is found within the catheter tip. Sensor tip is placed within the brain tissue and ventricle. It gives a direct measurement of brain pressure.

Question 34

Air pouch/Pneumatic technology

Answer 34

Air-filled pouch at the tip of the catheter that maintains a constant volume.

Question 35

How do you get an accurate reading of ICP with CSF device in place?

Answer 35

Close drain for 6 minutes | Monitor ICP waveform and mean ICP

Question 36

Major Complication for ICP monitoring?

Answer 36

Infection

Question 37

Intermittent Drainage

Answer 37

Open the system at indicated ICP and allow to drain for 2-3 minutes. Then close it after draining

Question 38

Continuous Drainage

Answer 38

Monitor for drained CSF volume | Strict aseptic technique

Question 39

LICOX and Neurovent catheters

Answer 39

Placed in healthy white matter of the brain | Measure brain oxygenation and temperature.

Question 40

Jugular Venous Bulb Oximetry

Answer 40

Measures oxygen in jugular vein using a catheter | SjvO2 should be 60-75%

Question 41

Mannitol (Osmitrol)

Answer 41

decreases ICP via plasma expansion and osmotic effect Monitor fluid and electrolyte status Contraindicated by renal disease

Question 42

Hypertonic Saline

Answer 42

Shifts fluids out of brain cells and into blood vessels. | Frequent monitoring of BP and serum sodium levels

Question 43

Corticosteroids

Answer 43

Treat vasogenic edema around tumors and abscess Improves CBF and restores autoregulation. Monitor fluid intake and sodium levels Monitor blood glucose Give antacids, histamine blockers or PPI to prevent GI ulcers and bleeding

Question 44

Barbituates

Answer 44

Reduces cerebral metabolism | Monitor pt's ICP, blood flow and EEG

Question 45

Ventriculostomy Indications

Answer 45

Hydrocephalus Cerebral Edema Increased ICP

Question 46

Decorticate Posturing

Answer 46

Flexor position Flexion position of arms, wrists, and fingers with adduction in upper extremities: extension, internal rotation and plantar flexion in lower extremities

Question 47

Nursing Management of ICP

Answer 47

GCS | Neuro Assessments include Assessing CN III, CN IV, and CN VI