Running Head: PEDIATRIC NEURO 1

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Running Head: PEDIATRIC NEURO 1 Pediatric Neurology Case Study Boyle, Molly; Chamberlain, Justine; Evans, Molly; Grubb, Adria; Lawrence, Kelsey; McMurray, Christa; Morris, Victoria; Wolcott, Ashley Northwest University Author Note Molly Evans, Buntain School of Nursing, Northwest University. Correspondence concerning this article should be addressed to Molly Evans, Buntain School of Nursing, Northwest University, 5520 108 th Ave NE, Kirkland WA 98033. E-mail: molly.evans10@northwestu.edu

PEDIATRIC NEURO 2 Cover Sheet Molly Evans: Editing & Introduction Adria Grubb & Ashley Wolcott: Pathophysiology Justine Chamberlain: Medications Kelsey Lawrence: Labs Molly Boyle: Assessments Victoria Morris & Christa McMurray: Diagnosis/Careplan

PEDIATRIC NEURO 3 Complex Pediatric Neurology Case Study Introduction Jason is a 5 year old boy who presents to his pediatrician s office with reports from his mother, Sarah, of vomiting, headaches, and that he has been unable to eat for the past two days. Upon further investigation, Jason has not had any recent fevers, seizures, diarrhea, or blank starring, but has appeared to be somnolent, irritable, more clumsy, and favoring his left side for the past few weeks. By the advice of the pediatrician, Jason is sent to Seattle Children s Hospital (SCH) for further assessment. Since arriving to SCH, Jason s vital signs and overall appearance has worsened, leading to an MRI and CT scan which reveals a large posterior fossa tumor. A ventriculostomy is placed to drain excess fluid with the plan to remove the tumor once Jason becomes stable. The plan changes into an emergency operation to remove the tumor after a code is called due to the development of hydrocephalus and cerebral edema. Jason has a ventriculostomy that needs to be monitored, along with his neurological status, ABGs, CBC and BNP labs. His only past medical history involves recurrent ear infections at the age of two. He is homeschooled and watched by his maternal grandmother when his divorced parents are unable to. Pathophysiology Hydrocephalus Hydrocephalus occurs when there is an excess of fluid within the cranium or subarachnoid space. It can occur when there is an overproduction of cerebrospinal fluid (CSF), a malfunction in the reabsorption of CSF, or when there is an obstruction that does not allow the circulating fluid to drian. Risk factors include the following: abnormal development of the

PEDIATRIC NEURO 4 central nervous system (CNS) that obstructs the flow of CSF, bleeding in the ventricles, infection in the uterus during pregnancy, lesions, tumors, bacterial meningitis, bleeding from a stroke or head injury, and traumatic brain injury. In Jason s case, the type of hydrocephalus presented is noncommunicating hydrocephlaus; an obstruction in the flow of CSF in the subarachnoid space. To be more specific, a large posterior foassa tumor is compressing the left ventricles and obstructing the flow of CSF through the brain. This will casue a dilation of the ventricles proximal to the site of the obstruction, resulting in an increase in intracranial pressure. If the fluid cannot escape or be rerouted, it will result in cerebral edema. This causes atrophy to the cerebral cortex which leads to degeneration of the white matter tracts in the brain. Selected parts of grey matter will also be degenerated while the non-selected parts of it will be preserved to preserve life. To better explain, the brain can find other pathways around damaged white matter, but cannot do so with damage to grey matter. Therefore the body works to preserve selected grey matter to perseverve the brain and its function (McCance, Huether, Brashers, & Rote, 2010, p. 560). Clincial manifestations of hydrocephalus may include; poor coordination, poor appetite, blurred or double vision, headache, enlargement of head, irritability, difficulty staying awake. Jason exhibits signs and symptoms of this through poor coordination, irritable and poor appetite ("Hydrocephalus," 2014). Cerebral Edema Cerebral edema is an increase in water accumulation in the extracellular or intracellular tissue of the brain. In this case, cerebral edema occured when the ventriculostomy that was supposed to be draining the excess CSF became blocked. There is excess water/csf accumulation in the brain and an increase in pressure. This type of cerebral edema is known as interstitial edema. Risk factors for cerebral edema include; head trauma, hyponatremia, high

PEDIATRIC NEURO 5 altitudes, brain tumor and obstructive hydrocephalus. Jason has two of these predisposing factors; a brian tumor and obstructive hydrocephalus. In noncommunicating hydrocephalus the brain will attempt to compensate for this increase in fluid by removing the fluid from the ventricles and absorbing the fluid in the extracellular spaces. This increases hydrostatic pressure within the white matter, however the actual size of white matter must decrease to compensate for the increased pressure. This is accomplished through the rapid loss of myelin lipids in the white matter (McCance, Huether, Brashers, & Rote, 2010, p. 559-560). Symptoms of cerebral edema can be: headaches, confusion, unconsciousness, or a coma. Jason exhibited headaches, and unconsciousness ("Edema: Types, Causes, Symptoms, and Treatment," 2013). Increased intracranial pressure Increased intracranial pressure (IICP) can be caused by any alteration that will cause increased pressure in the brain. Common causes of IICP include: aneurysm rupture, brain tumor, encephalitis, head injury, hydrocephalus, meningitis, subdural hematoma, stroke, and status epilepticus ("Increased Intracranial Pressure," 2011). In this case, there are many things that are causing an increase of matter and therefore IICP. The first thing that contributes to IICP is the large myelloblastoma that Jason has. The cells from the tumor are taking up space, thus cauisng IICP. Secondly, the tumor is causing noncommunicating hydrocephalus in which the CSF is not able to properly circulate and drain. This facilitates IICP because there is an excess of matter circulating and unable to drain. For Jason, CSF continues to increase pressure in the confined area of his skull. With this increase of CSF, the brain attempts to compensate and bring down the intracranial pressure by reabsorbing some of it into the extracellular space, which leads to cerebral edema. In essesnce, this causes the brain matter swell. All of this leads to the

PEDIATRIC NEURO 6 demyelinating the white matter of the brain. Without outside intervention the brain will continue this destructive cycle to reduce the IICP it is creating. Another concept to consider is that as the pressure increases, veins are compressed and the blood volume is reduced. As blood flow to the brain is slowed, a compromise of neuronal oxygenation will occur as well as systemic arterial vasocontriction to elevate systemic blood pressure to overcome the IICP. As the pressure continues to build, the brain tissue will experience hypoxia and acidosis. If the pressure still continues to rise, brain matter will herniate from the brain compartment with the highest pressure to a compartment with lower pressure. This further impairs the oxygenation to tissues and can lead to small hemorrhages within the brain tissue due to the enormous increase of pressure (McCance, Huether, Brashers, & Rote, 2010, p. 557-558). In this case, Jason s IICP was caught before herniation occurred. Signs and symptoms of IICP may include; drowsiness, vomiting, decreased consciousness, lethargy, headache, papilledema, seizues and vomiting ("Increased Intracranial Pressure," 2011). Headache Headache, a common neurological disorder, may be related to more serious diseases (McCance & Huether, 2010, p. 609). It is usually benign; however, in Jason s case it is the sign of a brain tumor a medulloblastoma. Brain tumors do not cause headache pain; rather, it is secondary to pressure within the cranial cavity. Increased pressure on nerves and pain-sensitive blood vessels in the brain is responsible for headaches in these cases as the brain tissue itself does not have pain receptors (American Brain Tumor Association, 2014). According to the American Brain Tumor Association, headache is amongst the most common experienced symptoms in individuals with brain tumors (2014). Little information on the qualities of Jason s headaches were provided so it is difficult to classify them.

PEDIATRIC NEURO 7 Medulloblastoma Medulloblastomas arise from immature cells in the cerebellum called embryonal cells (McCance & Huether, 2010, p. 687). They are considered high-grade tumors, meaning that they grow and spread quickly. Scientists are unsure of what causes these tumors to form; however, like most tumors, it is believed that genetics have a part to play. Medulloblastomas are the most common malignant tumor type found in children (McCance, Huether, Brashers, & Rote, 2010, p. 687). According to the Children s Brain Tumor Foundation, these tumors make up 20% of all pediatric tumors (2009). Also, of tumors occurring in the posterior fossa, they are the most common. These tumors are most commonly found in boys than in girls. This class of tumor is located in the cerebellum and often extends into both the fourth ventricle and spinal fluid pathway which is consistent with Jason s imaging results (McCance & Huether, 2010, p.686). Treatment of these tumors involves surgery to debulk the tumor as well as relieve intracranial pressure. Radiation and/or chemotherapy are often used in conjunction with surgery. Common clinical manifestations for a medulloblastoma include changes in appetite, changes in behavior, problems with coordination, headache, drowsiness, nausea, vomiting, and unusual eye movements (American Brain Tumor Association, 2014). When Jason presented to his pediatricians office, his mother reported him having had changes in appetite, headaches, vomiting, and loss of coordination. Jason also had had a left gaze preference that was observed by the physician as well as changes in behavior. These are consistent with what is seen in patients with a medulloblastoma. Jason s tumor and its involvement with the spinal fluid pathways and ventricles creates a whole list of complications. Because the tumor obstructs the normal flow of spinal fluid, an

PEDIATRIC NEURO 8 increase in intracranial pressure is seen as a result of hydrocephalus. This increase in pressure forces fluids out into the brain tissue causing cerebral edema. The brain is a complex organ; the slightest alteration to this system can seriously affect how the rest of the body functions and, if left unaddressed, could result in permanent damage. Assessment Five year-old Jason and his mother Sarah presented to the pediatricians office reporting symptoms of vomiting, headaches, and Jason being unable to eat for the last two days. Upon initial assessment and per Sarah s report, he has become more somnolent and irritable. Jason was in no acute distress during the visit, though remained in a fetal position when left alone. Jason s pupils were equal and reactive to light at this time, however some papilledema was present. A blood pressure was unable to be obtained because Jason was too irritable at the time, however heart sounds were normal with apical heart rate of 95, respiratory rate of 22, and afebrile. It was at this time that Jason was sent to the Emergency Department at Seattle Children s Hospital. Upon arrival to the ED, Jason was not as responsive, moaned upon assessment and tried to roll away from the nurse. Jason would not open his eyes or follow commands. When using the Glasgow Coma scale, this put Jason at a 7 for moaning (2), withdrawal from stimulus (4), and eyes not opening (1) (Perry, 2010, p. 1553). A score of 8 or below is generally accepted as a definition of coma, and is an emergent situation. His right pupil is 3mm and reactive while his left pupil is 5mm and sluggish. These findings are consistent with damage or compression of the third cranial nerve (Lewis, 2011, p. 1434-1435). Monitored vital signs were as follows: 65 heart rate, 145/84 blood pressure, respiratory rate of 14, and 96% oxygen saturation on room air. This too, is consistent with altered brain function and possible IICP with the Cushing s triad in which

PEDIATRIC NEURO 9 systolic hypertension is present with a widening pulse pressure, bradycardia, and irregular respirations (Lewis, 2011, p. 1429). An emergent CT and MRI were done to determine the cause for Jason s presentation. Both diagnostics were conclusive to show a large posterior fossa tumor with effacement of the fourth ventricle and basal cisterns, enlarged lateral and third ventricles and hydrocephalus. Postoperatively, Jason presents with equal and reactive pupils measured at 2mm. At this time he is able to respond by nodding his head to questions appropriately, which shows improvement from his prior state. His skin is warm and dry. His pulses are assessed as +2, capillary refill is 2 seconds, and his is currently on.5 liters of oxygen via nasal cannula. His ventriculostomy is set up to drain and the drainage is clear. The dressing is clean dry and intact. Later in the afternoon, Jason begins to complain of headaches that are unrelieved with pain medication and he later becomes unresponsive with sudden mental status changes. Jason s pupils are unequal and unresponsive to light at this point. These are all signs of possible cerebral edema, IICP, or potential brainstem herniation (Perry, 2010, p. 1573-1574). Upon assessment of the ventriculostomy, the nurse realizes that it has not drained in the last two hours. Signs of IICP present once again with a blood pressure of 164/90, oxygen saturation of 85%, and a respiratory rate of 6. After a subsequent CT scan, it is conclusive for hydrocephalus and cerebral edema. He is then sent for an emergent tumor resection. Postoperatively, Jason returns extubated and is arousable with a Glasgow coma score of 13 out of 15, indicating great improvement. The drainage from his ventriculostomy is clear but has a slightly pink tinge. His incision is on the occipit lower portion of his skull, approximated with staples, open to air, clean, dry and intact.

PEDIATRIC NEURO 10 Two days following the resection Jason is showing positive results with stable vital signs, neuro assessment and Glasgow coma score of 15. The MRI came back concluding that the ventricles now appear normal in shape and size. One concerning finding is that Jason s urine output has been 125mL for the last 4 hours and he is complaining of being extremely thirsty, showing possible signs of water retention especially when looking at his increased serum sodium levels. Jason s labs are grossly within normal limits, ABG: ph 7.38, PCO2 45mmHG, PO2 114mmHg, HCO3 22mEq/L, and Hct 35. Oxygen saturations are 97% on 1L of oxygen via nasal cannula. The abnormal lab values, Na 155, K+ 3.0, Cl 110, and glucose 102, could be related to side effects of drugs. The use of mannitol is a highly effective diuretic but generally reserved for severe cases because it is a major potassium wasting drug. The higher sodium and chloride levels could possibly be reflective of dehydration from the diuretic. Also, corticosteroids (Dexamethasone) are known to increase blood glucose levels as a side effect. He appears to be stable, though we will continue to monitor the status of his output and electrolyte levels. Labs/Diagnostics An MRI and CT scan were the diagnostic tests that were done on Jason to determine his neurologic problem. Not until the second day of hospitalization were any labs documented. Because of this, it was Jason s MRI and CT results that revealed his medulloblastoma and hydrocephalus. The later labs show the stabilization of his body 2 days into hospitalization. It would have been important to draw a daily/prn CBC, ABG, Glucose, and electrolyte panel every day that Jason was in the hospital in order to determine any systemic effects of the neurologic problems.

PEDIATRIC NEURO 11 Lab/ Diagnostic MRI CT Scan Normal Ranges Patient s Range Indication Images of the brain appear to be normal. Images of the brain appear to be normal. Large posterior fossa tumor, effacement of the fourth ventricle and basal cisterns, enlarged lateral and third ventricles, and hydrocephalus. (Abnormal) CT #1: Large posterior fossa tumor, effacement of the fourth ventricle and basal cisterns, enlarged lateral and third ventricles, and hydrocephalus. CT #2: hydrocephalus and cerebral edema (Both Abnormal) Sodium 135-145 meq/l 155 meq/l (High) Potassium 3.5-5.0 meq/l 3.0 meq/l (Low) The MRI is necessary to detect the tumor size and location as well as any other abnormalities that result from the tumor itself, such as ventricular enlargement/shortening, increased ICP, or hydrocephalus (Lewis, Dirksen, Heitkemper, Bucher, & Camera, 2011, p.1447). The CT scan is the fastest way to diagnose the location and comorbidities of a tumor or other neurologic problem. (Lewis et al., 2011, p.1447). It can also be used to determine treatment accuracy and monitoring of emergent situations, which is the indication for Jason s second CT scan. (Van Leeuwen, Poelhuis-Leth, Bladh, 2011, p. 464). These are the major cations of the body. They are monitored in this patient to ensure homeostasis within his body under the stress and fluid shifts within his brain. Sodium is high and potassium is low which could simply be to the stress of the tumor and fluid shifts. This could also be a side effect to Mannitol; a potassium wasting diuretic. This would be something to continue to monitor and trend since neither of them are critically abnormal (Van Leeuwen et al., 2011, p. 1074 & 1175). Cl 97-107 meq/l 110 meq/l (High) This is the major anion of the body and is monitored to ensure homeostasis. The chloride is most likely slightly high related to the patient s hypokalemia and hospital-related high intake of saline fluids (Van Leeuwen et al., 2011, p. 339-41). HCT 31-43% meq/l 35% meq/l The hematocrit is monitored to ensure

PEDIATRIC NEURO 12 Blood Glucose (Normal) hydration and that there is no active bleeds anywhere in the body (particularly in the brain). Jason s draw of HCT is only to monitor. (Van Leeuwen et al., 2011, p. 410). 60-100 mg/dl 102 mg/dl (High) Blood sugar levels become increased when the body is under stress. Because this level is only slightly high, it is most-likely due to stress. However, increased levels of blood glucose can be related to cerebrovascular issues such as a cerebrovascular accident, so this is an important lab to monitor (Van Leeuwen et al., 2011, p. 735). Hyperglycemia is a common side ABG ph: 7.35-7.45 PCO 2 : 34-45 mm Hg HCO 3 - : 22-26 mmol/l PO 2 : 80-100 mm Hg arterial 38-42 mm Hg venous. O 2 Saturation: >95% ph: 7.38 (Normal) CO 2 : 45 mm Hg (Normal) HCO 3 - : 22 mmol/l (Normal) PO 2 : 114 mm Hg (High) O 2 Saturation: 97% (Normal) effect to corticosteroids. The ABG is monitored to ensure the patient is adequately transferring oxygen and CO2 across the alveolarcapillary membrane and that there is adequate acidic and basic molecules to achieve homeostasis. Jason has normal levels aside from an elevated PO2, which leads me to believe that his low respiratory rate of 6 the previous day caused him to go into hypoventilation and respiratory acidosis. It is fully compensated now, but the PO2 is still high (Van Leeuwen et al., 2011, p. 254).