Increased intracranial pressure

Zainab Ramzan Ali

1. INCREASED INTRACRNIAL PRESSURE

"Brain swelling with edema and blood collects within the brain."

2. ANATOMY AND PHYSIOLOGY OF BRAIN:

* Brain the most critical organ of human body.

* Protected through three protective structures;

A. Skull-bony structure

B. Meningies-Dura, Arachnoid, Piamatter

C. Cerebrospinal Fluid.

3. PHYSIOLOGY OF INTRACRANIAL PRESSURE:

Intracranial pressure is normal at 4-15mmhg and 50-300mmof water. Skull is not flexible structure. If pressure of any of the above three will increase compensatory decrease in other two. If exceed the compensatory efforts increased intracranial pressure.

A. CEREBRAL BLOOD FLOW;

Brain injury can result from brain stem compression and reduction in cerebral blood flow.

Ohm's law

CBF = (CAP-JVP) \ CVR

CAP=CAROTID ARTERIAL PRESSURE

JVP= JUGLARVENOUS PRESSURE

CVR= CEREBROVASCULAR RESISTANCE

B. CEREBRAL PERFUSION PRESSURE;

A clinical surrogate for the adequacy of cerebral perfusion. CPP is defined as mean arterial pressure (MAP) minus ICP

CPP= MAP-ICP.

4. PATHOPHSIOLOGY:

Oedematous brain tissues lead to inflammation\hematoma formation

o increase pressure in the cranial cavity

o compensatory decrease in cerebral blood flow

o cerebral blood flow

o cerebral hypoxia

o ischemia of vasomotor centre

o CUSHING'S sign (increase B.P, decrease pulse) - late sign of increased intracranial pressure suggest irreversible brain damage.

5. CAUSES:

a. Mass lesion abscesses

b. Extadural hematoma

c. Subdural Hematoma

d. Subacutesubdural intracerebral hemorrhage

e. Stroke

f. Hepatic encephalopathy.

g. Brain Herniation

h. Seizures.

6. CLINICAL MANIFASTATION;

a. Severe Headache (e.g. head trauma, subarachnoid Hemorrhage)

b. Confusion or Diminished responsiveness

c. Hemiparesis

d. Seizers

e. Spontaneous periorbital bruising

f. Bradycardia

g. Respiratory Depression

h. Contra lateral papillary dilation

i. Loss of gag reflex

j. Glass cow coma scalelessthen or equals to 8

k. Temperature may rise

l. Cushing triad: increased systolic blood pressure, widened pulse pressure and slow heart rate.

m. Decorticate or decelerating posturing.

n. Occasional transient elevation associate with Sneezing, Cough,

DIAGNOSTIC FINDINGS

7. ROLE OF COMPUTED TOMGRAPHY:

CT scan may suggest elevated ICP based on the presence of mass lesion, midline shift. Since ICP monitoring is also associated with a small risk of serious complication that is CNS infection, intra cranial hemorrhage.

8. TYPES OF MONITORS

A. INTRVENTRICULAR;

Intraventricular monitors are considered the 'gold standard' of icp monitoring catheters. They are surgically placed into the ventricular system and a fixed into the drainage bag and pressure transducer with a three way stopcock .It allow the treatment of some elevated ICP via drainage of csf.

B. INTRAPARENCHYMAL;

Consist of a thin cable with an electronic or fiber optic transducer at the tip. The most widely used device is the fiber optic Camino system. These monitors can be inserted directly into the brain parenchyma via a small hole drilled in the skull. It cause ease of placement and lower the risk of infection.

C. SUBARACHNOID;

Subarachnoid bolts are fluid coupled systems within a hollow screw that can be placed through the skull adjacent to the dura. The dura is then punctured, which allows the CSF to communicate with the fluid column and transducer. The most commonly used subarachnoid monitor is the Richmond bolt. It has low risk of infection and hemorrhage.

D. TRANSCRANIAL DOPPLER:

Measures the velocity of blood flow with in the proximal cerebral circulation. TCD can be used to estimate ICP based on characteristic changes in waveforms that occur in response to increased resistance to cerebral blood flow. TCD is poor predictor of ICP, although in trauma patients. TCD finding may correlate with outcome at six months.

9. GENERAL MANAGEMENT:

Evacuation of a blood clot

Resection of a tumor

CSF diversion in the management of hydrocephalus

Treatment of underlying me

Metabolic disorder

10. SYMPTOMATIC TREATEMENT:

a. SEDATION AND BLOOD PRESSURE CONTROLING:

Keeping the patients appropriately sedated can decrease ICP by reducing metabolic demand, venous congestion and the sympathetic responses of hypertension and tachycardia.

b. POSITIONING:

Patient with elevated ICP should be positioned to maximize venous out floe from the head. Important maneuver including excessive flexion or rotation of the neck avoiding restrictive neck taping, minimizing stimuli that could induce valsalva responses, such as end tracheal suctioning. Keep head elevated above the heart level at 30 degree to increase venous outflow

c. FEVER:

Elevated metabolic demand in the brain results in increase cerebral blood flow and can elevate ICP by increasing the volume of blood in the cranial vault .Conversely; decreasing metabolic demand can lower ICP by reducing blood flow. Fever increase brain metabolism, and has been demonstrated to increase the brain injury in animal model. Aggressive treatment for fever includes acetaminophen and cooling.

d. HYPERVETILATION:

Use of mechanical ventilation to lower paco2 to 26 to 30 mmhg has been shown to rapidly reduce ICP through vasoconstriction and a decrease in the volume of intracranial blood

e. THERAPEUTIC HYPOTHERMIA:

Hypothermia decrease cerebral metabolism and may reduce ICP and cerebral Blood flow.

11. PHARMACOLOGICAL TREATEMENT:

a. ANTIEPILEPTIC THERAPY:

Seizures can both complicate and contribute to ICP Anti convulsant therapy with EEG done

b. MANNITOL:

It reduces brain volume by drawing free water out of the tissues and into circulation, where it exerted from the Kidney.

c. BARBITURATES:

The use of barbiturate s is predicated on their ability to reduce brain metabolism and cerebral blood flow, thus lowering ICP and exerting a neuroprotective effect.

12. SURGICAL TREATEMENT:

a. REMOVAL OF CEREBROSPINAL FLUID:

When hydrocephalus is identified, a ventriculostomy should be inserted, Slow removal can also be accomplished by passive gravitational drainage through the ventriculosomy.

b. DECOMPRESSIVE CRANICTOMY;

Decompresive cranictomy removes the rigid confines of the bony skull, increasing the potential volume of the intracranial content, cranictomy alone lowered ICP 15 PERCENT, but opening of the bony skull resulted in an average decrease in ICP of 70 percent.

13. NURSING DIAGNOSIS AND INTERVENTIONS:

a. NURSING DIAGNOSIS

Ineffective breathing pattern and ventilation related to hypoxia.

a. NURSING INTERVENTION:

Reassure person that measures are being taken to ensure safety.

Distract person from thinking about anxious state by having him or her maintain eye contact with you; say, "Now look at me breathe slowly with me like this".

Explain that one can learn to overcome hyperventilation through conscious control of breathing.

Discuss possible causes, physical and emotional and methods of coping effectively.

b. NURSING DIAGONSIS:

Altered Nutrition less than body requirement related to metabolic changes and inadequate intake.

NURSING INTERVENTION:

Determine daily caloric requirements that are realistic and adequate. Consult with dietitian.

Weight daily, Monitor laboratory results.

Explain the importance of adequate nutrition. Negotiate with client intake goals for each meal.

Plan care so that unpleasant or painful procedures do not take place before meals.

Provide pleasant, relaxed atmosphere for eat in (no bedpans insight).

Arrange plan of care to decrease or eliminate nauseatic odors.

Maintain good oral hygiene.

Try commercial supplement available in many forms (liquid, powder, pudding).

Establish intake goals with client, physician and nutritionist.

c. NURSING DIAGNOSIS:

Altered temperature related to damage to temperature regulating mechanism.

NURSING INTERVENTION:

Teach the person the importance of adequate intake (> or = 20,000ml per day unless contraindicated by heart or kidney disease)

Monitor intake and output.

Assess whether the clothing or bed covers are too warm for the environment.

Teach the importance of increasing fluid intake during warm weather and exercise.

Explain the need to wear loose fitting clothing.

Teach the early sign of hyperthermia or heat stroke.

Flushed skin.

Headache

Fatigue

Loss of appetite.

d. NURSING DIAGNOSIS:

Potential for impaired skin integrity related to bed rest and hemi paresis.

NURSING INTERVENTION:

Assess the integrity of skin.

Identify the stage of pressure ulcer development

Assess the status of ulcer: size, depth, edges, undermining.

Assess necrotic tissues, type, (color, consistency, adherence) and amount.

Wash reddened area gently with a mild soap rinse thoroughly to remove soap and pat dry.

Gently massage healthy skin around the affected area to stimulate circulation.

Increase protein and carbohydrate intake to maintain a positive nitrogen balance.

Weight the person daily.

Determine serum albumin level weekly to monitor status.

e. NURSING DIAGNOSIS:

Altered thought processes (deficit in intellectual function, communications) related to brain injury.

NURSING INTERVENTION:

Explain attitude about confusion (in self, caregivers, significant others) Provide education to family, significant others and caregiver regarding the situation and method of coping.

Maintain standard of empathic, respectful care.

Encourage significant others and care givers to speak slowly either low pitch and at an average volume.

Provide respect and promote sharing

Pay attention to what person is saying.

Pick out meaningful comments and continue talking.

Call person by name and introduce your self each time.

Use name the person is prefers, avoid "pops" or "moms"

Convey to person that you are concerned (through smile and unhurried pace).

Use memory aid if appropriate.

For communication

Use pad, pencil, alphabets, letters hand signals, eye link head nodes and bell signals.

Make flash cards with pictures or words depiciting frequently used phrases (Move my foot, glass of water).

Use normal loudness level, speak unhurriedly in short phrases.

Encourage person to take plenty of time talking and to enunciate word carefully with good lip movement.

Delay conversation when the person is tired.

f. NURSING DIAGNOSIS:

Impaired physical mobility related to increased intracranial pressure.

NURSING INTERVENTION:

Perform passive ROM exercise on affected limbs.

Support the extremity above and below the joint.

Use a footdrop.

Avoid a prolong period of sitting or lying in the same position.

Change the position of the shoulder joints every 2 to 4 hours.

Use a small pillow when in fowler's position.

Support the hands and wrist in natural alignment.

If the client is supine or prone, place a rolled towel or a small pillow under the lumbar curative or under the end of the rib cag.

If the client is in the lateral position, place pillow to support the leg from groin to foot and a pillow to flex the shoulder and elbow slightly; if needed, support the lower foot in dorsal flexion with a standing.

Use hand and wrist splints.

14. TEACHINGS:

o Back Care

o Hand and foot care

o Suctioning

o Medications

o Diet

o Deep breathing exercise

15. REHABILITATION THERAPY:

o Speech therapy

o Continuous GCS monitoring

o Memory orientation and repetition

o Swallowing therapy

o Use of assistive devices range of motion and walking

o Continues lab monitoring, aggressive chest physiotherapy

o Family teaching sessions




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About the Author
2006 All rights reserved
Zainab Ramzan Ali Physiology Of Intracranial Pressure.