Nursing Management of Hydrocephalus

Hydrocephalus is the abnormal accumulation of cerebrospinal fluid in the intracranial spaces. It occurs due to imbalance between production or absorption of CSF or due to obstruction of CSF pathways. It results in the dilation of the cerebral ventricles and enlargement of the head.

Etiology  / Causes :

It may occur due to congenital or acquired causes.

• Congenital Hydrocephalus: 

         It occurs due to following conditions:

1. Intrauterine infections : mainly in rubella, cytomegalovirus 
2. Congenital brain tumor obstructing the CSF flow.
3. Intracranial hemorrhage
4. Congenital malformation like aqueduct stenosis, displacement of brainstem and cerebellum, blocking of septum or membrane of outlet of the 4th ventricle.
5. Malformation of arachnoid villi.

• Acquired Hydrocephalus:

          It occurs usually in following conditions :

1. Inflammation : meningitis, encephalitis
2. Trauma : birth trauma , head injury , intracranial  haemorrhage 
3. Neoplasm : space occupying lesions like tuberculoma, subdural hematoma or abscess,etc. 
4. Chemical : hypervitaminosis A
5. Connective tissue disorder : hurler syndrome, achondroplasia
6. Degenerative atrophy of brain : Hydrocephalus Ex-vacuo
7. Arteriovenous malformations, ruptured aneurysm, etc. 

Classification :

1. Communicating hydrocephalus or non obstructive hydrocephalus :

    In this type , there is no blockage between ventricular system, the basal cisterns and the spinal subarachnoid space. There may be failure in the absorption of CSF or expressive production of CSF

2. Non-communicating hydrocephalus or obstructive hydrocephalus :

In this type, there is obstruction at any level in the ventricular system, commonly at the level of aqueduct or at foramina luschka. The obstruction may be partial, intermittent or complete. It develops mainly due to inflammation and development obstructive lesions. 

Pathophysiology :

Any imbalance of secretion, circulation and absorption causes acute retention of CSF in the ventricles.

↓

 Ventricular system gradually distant due to gradual increase of fluid pressure in ventricles.

                                                                                                                       ↓

Increased pressure compresses the brain substance against the surrounding rigid bony cranium  results in thinning of cerebral cortex and cranial bones especially in the frontal, parietal and temporal       areas.

                                                                                                                       ↓
The floor of the third ventricle bulges downward which compresses the optic nerve .

                                                                                                                       ↓

Enlargement of the skull as well as dilation of ventricles. 

Clinical Manifestations :

The clinical manifestations depends on the age of child.

• Infant :

1. Excesssive head growth .
2. Delayed closure of the anterior fontanelle .
3. Fontanelle tense and elevated above the surface of skull.
4. Signs of Increased Intracranial pressure (ICP) 
5. Alteration of muscle tone of extremities.
6. Frontal bossing (protuding forehead )
7. Sunset eyes ( pupil are low, white part are seen)
8. Difficulty in holding head up
9. The child may experience physical or mental developmental lag.

• In Older Children:

1. Children have closed sutures which are present with signs of increased ICP.
2. Vomiting
3. Restlessness and irritability 
4. High pitched cry
5. Rapid increase in head circumference 
6. Pupillary changes
7. Seizures, stupor , coma 
8. Visual changes
9. Changes in vital signs: ↑BP and temperature ,  ↓Pulse and respiration 

                          Fig. Difference between normal baby and baby with hydrocephalus.

Diagnostic Evaluation:

1. History Taking 
2. Physical Examination and Neurological assessment 

• Rapid head enlargement 
• Percussion of infant's skull may produce a typical "cracked pot" sound (Macewen's sign)
• Increase in head circumference more than 1 cm every 15 days. 
• Opthalmoscopy may reveal papilledema.
• CT scan and MRI reveal Ventricular enlargement or dilation as well as any structural defect if present.

Therapeutic Management :

1. Pharmacologic Management :

• Use of diuretics like acetazolamide (50 mg/kg/day) which excrete excessive CSF.
• Anticonvulsants to treat associated seizures disorders 
• Antibiotics to treat secondary CNS infections.

    2. Surgical Management :

• Removal of and obstruction like neoplasm.
• Placement of Shunt : Ventriculoperitoneal (VP) / Ventriculopleural / Ventriculoperitoneal shunt.

       Shunt system consists of a ventricular catheter, a flush pump, a unidirectional flow valve and a distal catheter. The valve is designed to open at a predetermined intraventricular pressure and close close when the pressure falls below that level prevent back flow of secretion.

                                               Fig. Ventriculo-peritoneal Shunt Mechanism

Complications of VP Shunt :
Infection, malfunction related to mechanical difficulties such as kinking, plugging or migration of tubing, mechanical obstruction due to exudate or thrombosis in distal part.

                                         Fig. Before and after the treatment by Ventriculo-peritoneal shunt

Prognosis :
Depends largely on the role of hydrocephalus development, the duration of increased ICP, the frequency of complications and the cause of the hydrocephalus.

Nursing Management of Hydrocephalus 

A) Pre-operative Care:

• Observe for evidence of increased ICP and report immediately. 
• Monitor Vital signs regularly.
• Measure the head circumference of the child  daily.
• Assess the pupillary response and level of consciousness .
• As the infant is irritable and restless, provide calm and quiet environment so that the infant may take adequate rest.
• Position the body adequately with neck adequately supported.
• As the scalp becomes thin, there is an increased chance for breakdown of scalp. so a water pillow or lamb's wool may be used to keep head over it.
• Change the infant's position frequently.
• Support the infant's head and neck while handling because the head may be too large and neck muscles may be too weak to support the head.
• The infant is prone to vomitting, so provide small, frequent feedings with intermittent burping.
• Keep the infant clean and dry.
• Encourage the parents to discuss all the risk and benefit of surgery.

B) Post-operative Care :

• Post operatively , place the infant in flat position to prevent rapid CSF drainage ad on unsupported side to avoid pressure on the valve of shunt . If CSF is drained too rapidly there is a risk of subdural hematoma caused by tearing of the vessels secondary to the cerebral cortex pulling away from the duramater.
• Check vital signs every 15-30 minutes in immediate post operative period.
• Assess the neurological status and level of consciousness frequently.
• Assess the head circumference regularly.
• Monitor the intake and output as fluids may be restricted during 24 hours post operatively.
• Oral rehydration must be started after the bowel sound reappear.
• Check dressings for any drainage.
• The child must be observed for signs of infection such as fever , increased heart and respiratory rate, poor feeding or vomiting, altered mental status and local symptoms such as redness or CSF leakage at the surgical site.
• Prophylactic antibiotics are administered as prescribed to prevent infections.
• Teach parents about care of the child at home, after discharge from hospital.
• Tell them about:

1. Holding the baby while feeding and positioning the child.
2. Recognizing the signs of increased ICP and malfunctioning or blockage of shunt.
3. Pumping of the shunt in case of increased ICP.
4. Preventing constipation if the child has Ventriculoperitoneal shunt as straining during defecation may increase the ICP.
5. Importance of follow up care.

                                                                            Dawa Lhomu Sherpa(Yangla)

                                                                                                     Bsc.Nurse (RN) , Nepal