Hydrocephalus Hydrocephalus

• The term hydrocephalus is derived from the Greek words "hydro" meaning water and "cephalus" meaning head.

• Hydrocephalus results from an imbalance between production and absorption of CSF.

• The balance between production and absorption of CSF is critically important.

• When production is more than absorption, CSF accumulates within the ventricular system producing the dilation of the spaces in the brain called ventricles.

• The ventricular system is made up of four ventricles connected by narrow pathways.

• Normally, CSF flows through the ventricles, exits into cisterns (closed spaces that serve as reservoirs) at the base of the brain, bathes the surfaces of the brain and spinal cord, and then is absorbed into the bloodstream.

• Ideally, the fluid is almost completely absorbed into the bloodstream as it circulates; however, there are circumstances which, when present, will prevent or disturb the production or absorption of CSF, or which will inhibit its normal flow. When this balance is disturbed, hydrocephalus is the result.

Flow of CSFFlow of CSF• lateral ventricles--> foramen of

Monro third ventricle --> aqueduct of Sylvius --> fourth ventricle --> foramina of Magendie and Luschka --> subarachnoid space over brain and spinal cord --> reabsorption into venous sinus blood via arachnoid granulations.

Incidence Incidence • Occurs in 3 - 4 cases in every 1000

births.

• Hydrocephalus may be

Communicating Non – communicating ( obstructive )

Communicating hydrocephalusCommunicating hydrocephalus

• There is no blockage between the ventricular system, the basal cisterns and the spinal subarachnoid space.

• Failure in the absorption system- unknown cause

• Excessive production of CSF- tumor or unknown cause

Obstructive or Obstructive or Non-Communicating hydrocephalusNon-Communicating hydrocephalus

• The block is at any level in the ventricular system (source of production and area of its reabsorption), commonly at the level of the aqueduct or foramina of Luschka and Magendie.

• There are two other forms of hydrocephalus which do not fit distinctly into the categories mentioned above and primarily affect adults:

1. Hydrocephalus ex-vacuo and 2. Normal pressure hydrocephalus.

• Hydrocephalus ex-vacuo: Hydrocephalus ex-vacuo occurs when there is damage to the brain caused by stroke or traumatic injury. In these cases, there may be actual shrinkage (atrophy or wasting) of brain tissue. In cerebral atrophy ventricles are dilated but pressure is not raised .

• Normal pressure hydrocephalus. Normal pressure hydrocephalus commonly occurs in the elderly and is characterized by memory loss, dementia, gait disorder, urinary incontinence, and a general slowing of activity.

Causes Causes Hydrocephalus can be congenital or

acquired.• Congenital hydrocephalous:

Intrauterine infections ( rubella, cytomegalovirus, toxoplasmosis),

Intracranial & intraventricular bleed.Midline tumorsCongenital malformations

• Acquired hydrocephalous:

TuberculosisChronic and pyogenic meningitisIntraventricular hemorrhagePosterior fossa tumors:

medulloblastoma, astrocytoma, ependymoma

Arteriovenous malformationIntracranial hemorrhageRuptured aneurysm

Pathophysiology Pathophysiology • The ventricles become greatly

distended

• The increased ventricular pressure results in thinning of the cerebral cortex and cranial bones especially frontal, parietal and temporal areas.

• The floor of the third ventricle commonly bulges downward, compress the optic nerves

• The basal ganglia, brain stem and cerebellum remain relatively normal but compressed

• The choroid plexus is usually atrophied to some degree.

Clinical manifestationsClinical manifestations• Symptoms of hydrocephalus vary with

age, disease progression, and individual differences in tolerance to CSF. For example, an infant's ability to tolerate CSF pressure differs from an adult's. The infant skull can expand to accommodate the buildup of CSF because the sutures (the fibrous joints that connect the bones of the skull) have not yet closed.

In infancy• The most obvious indication of

hydrocephalus is often the rapid increase in head circumference or an unusually large head size.

• Delayed closure of the anterior fontanelle, tense and elevated.

• Spasticity of muscles of extremities• Later signs: bossing of forehead,

scalp appears shiny with prominent scalp veins, eyebrows and eyelids drawn upward, sunset eyes in infants, difficulty holding head, strabismus, nystagmus, optic atrophy, physical and mental development lag

• Older childrenOlder children have closed sutures and

present with signs of IICP.

Signs of increased ICPSigns of increased ICP• Vomiting, sleepiness, restlessness,

irritability, high pitched shrill cry ( infant), tensed bulging fontanelle ( infant), rapid increase in head circumference ( infant),

• Changes in vital signs ( increased systolic pressure, decreased pulse, decreased and irregular respiration, increased temperature), pupillary changes, papilledema, lethargy and stupor, coma, seizures.

• Older children may also experience; headache, especially on awakening, lethargy, fatigue, apathy, problems with balance, poor coordination, gait disturbance, urinary incontinence, personality changes, separation of cranial sutures ( upto 10 yrs ) visual changes ( double vision )downward deviation of the eyes (also called "sunsetting").

Diagnostic evaluationDiagnostic evaluation• Physical examination infant’s head

transilluminates, Macewen’s sign ( cracked pot sound on percussion )

• Ophthalmoscopy • CT scan• Skull x-ray• Ventriculography ( rare )

Treatment Treatment • SurgicalDirect operation on the lesion causing obstruction

such as tumor

Intracranial shunts to divert fluid in noncommunicating hydrocephalus from ventricular system to the subarachnoid space

Extracranial shunts to divert fluid from ventricular system to an extracranial compartment frequently peritoneum or right atrium

Complications Complications • Complications may include mechanical

failure, infections, obstructions, and the need to lengthen or replace the catheter.

• Generally, shunt systems require monitoring and regular medical follow up. When complications do occur and due to growth of child, usually the shunt system will require some type of revision.

• Child with V-A shunt may experience endocardial contusion, clotting, leading to bacterial endocarditis, bacteremia, thromboembolism.

Nursing diagnosisNursing diagnosis• Altered cerebral tissue perfusion r/t

IICP • Altered nutrition ( less ) r/t reduced

oral intake and vomiting• Risk of impaired skin integrity r/t

alteration in level of conciousness and enlarged head

• Anxiety r/t surgery

• Risk for fluid volume deficit r/t CSF drainage, decreased intake postoperatively

• Risk for injury r/t malfunctioning shunt, infection

• Ineffective family coping r/t diagnosis and surgery