1. INTRACRANIAL PRESSURE

2. Intracranial Pressure
Refers to the pressure contained within the cranial cavity.
The normal range is between 0 to 15 mmHg.
ICP over 20 mm/Hg is considered elevated ICP, also known as intracranial hypertension.
The management team becomes concerned whenever a patient’s ICP is over 15 mm/Hg, but is especially concerned when it reaches levels of intracranial hypertension.

3. Intracranial Pressure
Skull has three essential components:
- Brain tissue = 78%
- Blood = 12%
- Cerebrospinal fluid (CSF) = 10%
Any increase in any of these tissues causes increased ICP

4. Components of the Brain
Fig. 55-1

5. Factors that influence ICP
Arterial pressure
Venous pressure
Intraabdominal and intrathoracic pressure
Posture
Temperature
Blood gases (CO2 levels)

6. Intracranial Pressure
The degree to which these factors  ICP
depends on the ability of the brain to
accommodate to the changes

7. Regulation and Maintenance for ICP
If the volume in any one of the components (brain tissue, blood, and CSF)
increases within the cranial vault and the volume from another component is displaced, the total intracranial volume will not change

8. Intracranial Pressure Regulation and Maintenance
Normal compensatory adaptations
Alteration of CSF absorption or production
Shunting of CSF into spinal subarachnoid space
Shunting of venous blood out of the skull

9. Mechanisms of Increased ICP
Causes
Mass lesion
Cerebral edema
Head injury
Brain inflammation
Metabolic insult

10. Increased Intracranial Pressure Mechanisms of Increased ICP
Sustained increases in ICP result in brainstem compression and herniation of the brain from one compartment to another

11. Increased Intracranial Pressure
Fig. 55-3

12. Herniation
Fig. 55-4

13. SITES FOR ICP MONITORING Epidural Subarachnoid Intraventricular

14. ICP mentoring system

15. ICP mentoring system

16. Nursing Care: Assessment
Change in level of consciousness
Changes in vital signs (Cushing triad)
Widening pulse pressure
Tachy/Bradycardia
Increased systolic BP
Irregular respirations

17. Nursing Care: Assessment
Ocular signs
Decrease in motor strength and function
Assess movement
Assess response to stimuli
Assess:
Decerebrate posturing (extensor)
Indicates more serious damage
Decorticate posturing (flexor)

18. Decorticate and Decerebrate Posturing

19. Nursing Care: Assessment
Headache
Often continuous and worse in the morning
Vomiting
Not preceded by nausea
Projectile

20. Increased Intracranial Pressure Collaborative Care
Hyperventilation therapy: suctioning →
hyperventilate with 100% oxygen
Adequate oxygenation
PaO2 maintenance at 100 mm Hg or
greater
ABG analysis guides the oxygen therapy
May require mechanical ventilator

21. Increased Intracranial Pressure Collaborative Care
Drug therapy
Mannitol
Loop diuretics
Corticosteroids
Barbiturates
Antiseizure drugs

22. Increased Intracranial Pressure Collaborative Care
Nutritional therapy
Patient is in hypermetabolic and hypercatabolic state
 Need for glucose
Keep patient normovolemic
IV 0.45% or 0.9% sodium chloride

23. Increased Intracranial Pressure Nursing Management
Overall goals:
ICP WNL
Maintain patent airway
Normal fluid and electrolyte balance
No complications secondary to immobility
Respiratory function
Fluid and electrolyte balance

24. Increased Intracranial Pressure Nursing Management
Overall goals (cont’d)
Body position maintained in head-up position: elevate HOB 30°
Protection from injury: positioning/turning
Pain control
Psychological considerations