Chapter 37 Hydrocephalus
PATHOPHYSIOLOGY
Hydrocephalus may be congenital or acquired. Congenital hydrocephalus is frequently associated with other congenital neurologic disorders or malformations. Some of the most commom associated diagnoses are myelomeningocele, Arnold-Chiari malformation, and aqueduct stenosis. The genetic factors that lead to hydrocephalus are unknown, with the exception of congenital X-linked hydrocephalus, which accounts for less than 4% of all cases. Acquired hydrocephalus may be caused by maternal malnutrition, intrauterine infections, tumors, vascular malformations, abscesses, intraventricular cysts, intraventricular hemorrhage, meningitis, and cerebral trauma. Causes of hydrocephalus are commonly labeled as idiopatic, infectious, hemorrhagic, posttraumatic, or tumor-related. Regardless of the cause, the result is a blockage of cerebral spinal fluid (CSF) flow and absorption secondary to microscopic changes in the CNS tissue or mechanical obstruction of the CSF circulation. Less than 0.5% of all cases of hydrocephalus are caused by overproduction of CSF. Excessive accumulation of CSF leads to ventricular enlargement and increased intracranial pressure (ICP) that may contribute to further CNS tissue damage. Children with hydrocephalus are at risk for both physical and cognitive delays; however, many benefit from physical and educational interventions and go on to live happy, healthy lives.
CLINICAL MANIFESTATIONS
Signs and symptoms are the results of ICP and vary with the child’s age and the skull’s ability to expand.
Infants
LABORATORY AND DIAGNOSTIC TESTS
See Appendix F for normal values and ranges of laboratory and diagnostic tests.
1. Computed tomographic scan—used to determine the degree of venticular enlargement and the etiology of the hydrocephalus; also used to evaluate shunt for possible malfunction if symptoms return
2. Magnetic resonance imaging—used to determine the degree of ventricular enlargement and the etiology of the hydrocephalus; also used to evaluate shunt for possible malfunction if symptoms return
3. Ultrasound may be used in very young infants who have open fontanelles.
SURGICAL MANAGEMENT
The traditional management is surgical shunt insertion. The shunt removes the excess CSF and decreases ICP. The proximal end of the shunt is inserted in the lateral ventricle; the distal end is extended to the peritoneal cavity or the right atrium as a means of draining excessive fluid into another body cavity. The ventricular-peritoneal (VP) shunt is used most frequently, because the atrioventricular shunt is associated with higher risks. An endoscopic third ventriculostomy creates an outlet for the CSF in the floor of the third ventricle, but is indicated only in a limited number of patients. Even though first-year failure rates of VP shunts are as high as 40%, this is still the treatment of choice in most patients.
NURSING INTERVENTIONS
Preoperative Care
1. Monitor for, prevent, and intervene in case of increased ICP.
Postoperative Care
1. Monitor child’s vital signs and neurologic status; report signs of increased ICP (decreased LOC, anorexia, poor or ineffective sucking, vomiting, convulsions, seizures, or sluggishness).
2. Monitor and report signs of infection (fever, tachycardia, general malaise, tenderness, inflammation, nausea, and vomiting).
3. Monitor and maintain functioning of shunt.
4. Monitor for pain and provide nonpharmacologic and pharmacologic measures to relieve pain (refer to Appendix I).
5. Support child and parents to help them deal with emotional stresses of hospitalization and surgery (refer to the Supportive Care section in Appendix F).
Discharge Planning and Home Care
1. Instruct parents to monitor for and report signs of shunt complications.
2. Provide parents with assistance in contacting community resources.
3. Encourage parents to increase fluid and roughage in child’s diet to prevent constipation, because straining at passing stool causes increased ICP.
4. Assess cognitive, linguistic, adaptive, and social behaviors to determine development; use developmental history to assess achievement of early milestones and refer to appropriate specialists as needed.
CLIENT OUTCOMES
1. Child will not have signs or symptoms of increased ICP.
2. Child will not have signs or symptoms of infection.
3. Child’s skin will remain clean, dry, and intact, without signs of erythema or ulceration.
4. Child and parents will understand how to monitor for and report shunt complications.
5. Child will demonstrate regular, observable growth and achieve age-appropriate developmental milestones.
6. Parents will be able to describe hydrocephalus and how it affects their child; identify measures used to treat the disorder; and state realistic expectations about their child’s condition following shunt insertion.
Kestle JRW. Pediatric hydrocephalus: Current management. Neurol Clin North Am. 2003;21:883.
National Institute of Neurological Disorders and Stroke (NINDS). Hydrocephalus fact sheet. (website) www.ninds.nih.gov, April 26, 2006. Accessed April 26, 2006
Pattisapu JV. Etiology and clinical course of hydrocephalus. Hydrocephalus. 2001;36(4):351.
Simpkins CJ. Ventriculoperitoneal shunt infections in patients with hydrocephalus. Pediatr Nurs. 2005;31(6):457.
