Chapter 54 lecture
Neurological System Components
Brain, Spinal Cord, and Nerves: These are the primary components that make up the neurological system.
Meninges:
Three protective membranes that surround the brain and spinal cord, acting as a form of insulation.
Meningitis: Inflammation of these protective membranes.
Cerebrospinal Fluid (CSF):
Purpose: Protects, nourishes, and supports the brain and spinal cord.
Function: Acts as a shock absorber. Without CSF, the brain's weight (approximately g, mostly fat) would compress itself.
Hydrocephalus: Occurs when there is an excessive amount of cerebrospinal fluid.
Detecting CSF Leak: A "halo sign" (a ring of clear fluid around a central bloodstain) on a white napkin can indicate CSF draining from the nose or ear.
Glucose in CSF: There should be glucose present in cerebrospinal fluid, which can help differentiate it from other discharges.
Formation: CSF is formed in the first trimester of pregnancy. Any insult during gestation can lead to malformations in the central nervous system.
Neurological Maturation: The neurological system matures from birth up to years of age. The brain continues to grow through puberty.
Brain Oxygen Deprivation and Damage
Lack of Blood Supply: Results in a lack of oxygen to the brain.
Timelines for Irreversible Brain Damage:
minute: Brain cells begin to struggle; consciousness may be lost.
minutes: Brain cells begin to sustain damage.
minutes: Permanent brain damage occurs.
minutes: Damage becomes irreversible.
More than minutes: Leads to brain death.
Clinical Relevance (CPR): Patients undergoing extended CPR ( minutes) who regain a heartbeat often suffer severe brain damage due to prolonged oxygen deprivation, necessitating artificial life support indefinitely.
Critical Threshold: The goal is to limit oxygen deprivation to no more than minutes to prevent significant brain damage.
Myelination and Primitive Reflexes
Myelination: The process by which the myelin sheath forms around nerves. As myelination increases, primitive reflexes disappear.
Primitive Reflexes (that should disappear in infancy/early childhood):
Rooting reflex
Moro (startle) reflex
Stepping reflex
Babinski reflex (should not be present in children > years or adults)
Assessment of Level of Consciousness (LOC)
Distinguishing Terms:
Mental Status: Refers to a person's overall cognitive and emotional functioning, including orientation, memory, attention, language, judgment, mood, and thought processes.
Level of Consciousness (LOC): Pertains to a person's responsiveness and awareness. An "altered level of consciousness" indicates a lack of responsiveness.
Orientation: Assesses awareness of person, place, time, and situation (often documented as "alert and oriented x 4").
Assessing Alertness:
Calling the patient's name.
Verbal stimulation (e.g., screaming "Hello!").
Painful stimuli (e.g., sternal rub) if no response to verbal cues.
Abnormal Posturing: Indications of serious brain injury and increased intracranial pressure (ICP).
Decorticate Posturing (Flexor): Arms adducted and flexed, wrists and fingers flexed on the chest. Indicates damage to the corticospinal tracts.
Decerebrate Posturing (Extensor): Arms adducted and extended, wrists pronated, fingers flexed, legs extended, and feet plantar flexed. Considered a worse prognosis than decorticate posturing, indicating brainstem damage.
Glasgow Coma Scale (GCS)
Purpose: An objective tool used to quantify a patient's level of consciousness and assess brain function. It is not exclusively for patients in a coma.
Three Components of Assessment:
Eye Opening: (e.g., spontaneous, to sound, to pressure/pain, no response)
Verbal Response: (e.g., oriented, confused, incongruous words, incomprehensible sounds, no response)
Motor Response: (e.g., obeys commands, localizes pain, normal flexion, abnormal flexion, extension, no response)
Scoring: Scores are assigned for each component and summed.
Maximum Score: (indicates normal neurological function).
Minimum Score: .
Severe Head Injury: A score of less than is indicative of severe head injury and typically necessitates intubation due to inability to maintain an airway.
Pupillary Assessment
Unilateral Dilated Unreactive Pupil:
Association: Frequently associated with an intracranial mass.
Significance: Can indicate impending brainstem herniation, where the brain is pushed out of the skull due to increased intracranial pressure.
Bilateral Fixed and Dilated Pupils:
Significance: Suggests that brainstem herniation has occurred from increased intracranial pressure, which is a critical and often fatal sign.
Cranial Nerve Assessment
Importance: A full neurological assessment requires the testing of cranial nerves I through XII. Though challenging, accurate documentation is crucial for patient care and for providing information to emergency medical personnel.
Efficiency: Some cranial nerves can be assessed simultaneously to expedite the examination process.
Seizures and Status Epilepticus
Epilepsy: A chronic neurological disorder characterized by recurrent unprovoked seizures. It involves periods of remission and exacerbation.
Triggers: Can be triggered by stress, menstrual cycles (menses), or infection. Identifying and preventing these triggers is key to management.
Aura: A subjective sensation or perception that may precede a seizure, serving as a warning sign (e.g., specific smells like burnt popcorn, flashing lights).
Seizure Types (Varies by age):
Partial seizures
Generalized seizures
Febrile seizures: Caused by fever.
Absent seizures: Characterized by a "blind stare into space" or sudden blank spells.
Neonatal Seizures: Can be subtle, presenting as sustained eye opening, roving eye movements, repetitive blinking, sucking, lip smacking, tongue thrusting, swimming movements of the arms, leg pedaling movements, apnea, or tachycardia.
Status Epilepticus:
Definition: A seizure lasting longer than 30 minutes, or a series of seizures without full recovery of consciousness between them.
Physiological Impact: Leads to severe electrolyte imbalances, glucose depletion (hypoglycemia), deranged arterial blood gases (ABGs), hyperthermia, and unstable blood pressure due to continuous muscular contractions.
Oxygen Demand: The basal metabolic rate significantly rises during seizure activity, dramatically increasing the demand for oxygen and glucose in the brain, leading to cerebral hypoxia.
Incidence: The highest incidence of status epilepticus is in the first months of life.
Treatment of Seizures:
Febrile Seizures: Typically not treated with anticonvulsants if the seizure has stopped and the underlying cause is fever. Fever-reducing medications are administered.
Non-Febrile Seizures: Treated with anti-seizure medications, usually started at a low dose and gradually increased.
Discontinuation: Anti-seizure medications should never be stopped abruptly, as this can lead to severe withdrawal and rebound seizures.
Medication Management and Education:
Driving Restrictions: Adolescents newly prescribed anti-seizure medications should refrain from driving for weeks to assess their reaction to the medication.
Alcohol: Contraindicated while on anti-seizure medications.
Mental Health Monitoring: Patients on anti-seizure medications should be monitored for depression and suicidal ideation, as these are known side effects.
Emergency Assessment and Management of Status Epilepticus:
Priority: Airway Management (ABC's): Maintain a patent airway. Oxygen should be administered during the seizure, not withheld, as brain oxygenation is critical.
Bedside Equipment: Suction must be readily available.
Tongue Depressor: Never insert a tongue depressor or anything else into the mouth of a seizing patient.
Monitoring: Continuous vital signs monitoring with pulse oximetry and cardio-respiratory monitoring. Neurological assessments should be performed every minutes.
Intravenous (IV) Access: Establish IV access for fluid and medication administration. This can be challenging in a seizing patient but is crucial.
Blood Glucose: Assess blood glucose levels and administer glucose as needed, due to the physical stress of the seizure causing declining glucose levels.
NG Tube: An NG tube may be inserted to reduce the risk of aspiration, especially if vomiting occurs.
Injury Protection (Seizure Precautions): Protect the child from injury by placing the bed in the lowest position, raising side rails, and considering a helmet if appropriate.
Temperature Management: Manage thermal regulation.
Pharmacological Interventions:
Benzodiazepines (e.g., Lorazepam/Ativan): First-line treatment. Administer via slow IV push (typically over minutes, as per drug guide; "slow" is not subjective). Monitor for hypotension, tachycardia, and respiratory depression. May be repeated if no response.
Phenobarbital: May be used if seizure activity continues, but high doses can cause apnea. Be prepared for ventilatory assistance and intubation.
Phenytoin (Dilantin):
Side Effects: Frequent dental care is needed due to potential gingival hyperplasia (overgrowth of gums). Urine may turn pink-red-brown.
Administration: Can cause severe hypotension and cardiac arrhythmias if administered too rapidly.
Levetiracetam (Keppra): Monitor for suicidal tendencies, especially in patients with a history of psychosis or depression.
Other medications like valproic acid, gabapentin (Neurontin), and topiramate (Topamax, sometimes used off-label for weight loss) are also used.
Post-Seizure Goals: Prioritize airway, ensure safety, administer appropriate medications, glucose, and oxygen. Provide pain management, emotional support, and thorough education to the patient and family.
Meningitis
Definition: Inflammation of the meninges (the protective membranes covering the brain and spinal cord).
Types: Can be either viral or bacterial.
Vaccination: Vaccines are available, primarily for bacterial meningitis, but cases can still occur.
Bacterial Meningitis:
Severity: More serious than viral meningitis, often fatal, and can lead to sepsis.
Causes: Can also be caused by tuberculosis (TB).
Symptoms:
General: Fever.
Infants: Changes in feeding patterns, vomiting, diarrhea, bulging or tense fontanelles, restlessness, lethargy, irritability.
Older Children: Altered level of consciousness (confusion, lethargy, irritability), classic nuchal rigidity (stiff neck), and hyperextension of the head and neck (opisthotonos) as the only comfortable position.
Specific Clinical Signs:
Kernig's Sign: To test, raise the child's leg with the knee flexed, then extend the leg at the knee. A positive sign is resistance and pain due to stretching of inflamed meninges.
Brudzinski's Sign: To test, with the child in a supine position, flex the child's head towards the chest. A positive sign is involuntary flexion of the hips and knees.
Risk Factors: Infants are at the greatest risk. Otitis media (middle ear infection) or sinusitis can predispose to bacterial meningitis.
Viral Meningitis:
Symptoms: Similar to bacterial meningitis but generally less severe; the child does not appear as acutely ill.
Treatment Approach:
Empiric Antibiotics: Due to the potential fatality of bacterial meningitis, broad-spectrum antibiotics are typically administered immediately on an emergency basis, before culture results are available, until bacterial meningitis can be definitively ruled out.
Antibiotics are ineffective against viral meningitis but are given prophylactically in case of bacterial etiology.
Encephalitis
Definition: Inflammation of the brain itself.
Reye Syndrome
Cause: Primarily associated with aspirin administration during or following a viral illness (e.g., influenza, varicella).
Pathophysiology: Characterized by an acute encephalopathy (brain dysfunction) and fatty infiltration of the liver, resulting from a toxic, inflammatory, or anoxic insult or injury. Can lead to permanent tissue damage.
Symptoms: Typically follows a viral illness with an acute onset of vomiting, mental status changes, seizures, and progressive unresponsiveness.
Complications: Can lead to cerebral edema, coma, seizures, and respiratory arrest.
Prevention Teaching: Advise parents to use acetaminophen or ibuprofen instead of aspirin for children during viral illnesses.
Guillain-Barré Syndrome
Definition: A rare, acute inflammatory peripheral neuropathy characterized by rapidly developing symmetric motor weakness that ascends (starts in the lower extremities and progresses upwards).
Prognosis: Paralysis of respiratory muscles is a severe and life-threatening complication.
Incidence: Rare in children.
General Acute Neurological Condition Management
Assessment Priorities:
Vital signs (including pulse oximetry and respiratory rate)
Pain assessment
Head circumference (especially in infants, to monitor for increasing intracranial pressure)
Monitoring for changes in condition and response to treatment.
Interventions:
Medication administration
Maintaining adequate hydration
Ensuring skin integrity
Providing appropriate nutrition
Complication Prevention: Prevent complications associated with immobility, such as pneumonia.
Support: Promote comfort, provide emotional support to the child and family, and offer comprehensive education.
Hydrocephalus
Definition: An imbalance between the production and absorption of cerebrospinal fluid (CSF), leading to an accumulation of CSF within the brain's ventricles.
Etiology: Can be congenital (present at birth) or acquired (e.g., after hemorrhage, meningitis, traumatic brain injury (TBI), or a brain tumor).
Symptoms:
Newborns/Infants: Rapidly increasing head circumference (monitor regularly until approximately years of age), irritability, vomiting, poor feeding, disordered sleep, fever.
Older Children: Headache, nausea, vomiting, and decreased level of consciousness.
Pathophysiology: Enlarged ventricles exert pressure on and compress the brain tissue. If left untreated, this can lead to brain herniation, which is often fatal.
Treatment: Shunt Placement:
Shunt: A medical device surgically placed to drain excess CSF from the ventricles to another body cavity (e.g., peritoneum) where it can be absorbed.
Shunt Malfunction: Presents with signs of increased intracranial pressure (ICP), such as irritability, vomiting, poor appetite, disordered sleep, and fever in infants; or headache, nausea, vomiting, and decreased LOC in older children.
MRI Considerations: Patients with shunts containing metallic components (e.g., certain pressure valves) may be unable to undergo MRI scans.
Nursing Care:
Pre-operative Care: Provide routine preparation for surgery.
Post-operative and Ongoing Monitoring:
Regularly assess and compare head circumference measurements.
Monitor for any signs of increased ICP.
Be vigilant for shunt malfunction.
Watch for signs of infection, as shunts can be a source of infection.
Parent Education: Educate parents on monitoring for complications and provide emotional support.
Head Injury & Sleep (Myth Clarification): The common instruction "don't let them go to sleep" after a head injury is not because sleep itself is harmful, but because continuous monitoring of neurological status (LOC, vomiting, etc.) is necessary to detect signs of increased ICP.
Spina Bifida (Neural Tube Defect)
Definition: A malformation of the spinal cord and spinal canal, where one or more vertebrae fail to close properly, allowing spinal contents to protrude.
Location: Can occur anywhere along the vertebral column but is most common in the lumbar or sacral region.
Etiology: The exact cause is unknown, but it is strongly associated with certain factors during early pregnancy, including alcohol consumption, specific medications, and, most importantly, a lack of folic acid intake by the mother.
Presentation: Characterized by a sac-like protrusion on the infant's back. The degree of paralysis, weakness, and sensory loss depends on the severity and exact location of the defect.
Associated Complications:
Bowel and Bladder Incontinence: A universal complication, often involving a neurogenic bladder requiring management such as clean intermittent catheterization.
Renal Damage: Can result from neurological impairment and urinary retention.
Mobility Problems: Varying degrees of motor deficits.
Intellectual Disability and Seizure Disorders: Potential neurological sequelae.
Visual Impairment
Musculoskeletal and Joint Abnormalities
Treatment: Surgery:
Timing: Surgical closure is typically performed within hours after birth to reduce the risk of infection.
Pre-operative Care:
The sac should be kept sterile and moist with a non-adherent dressing.
The newborn is placed in a prone position with hips slightly flexed and legs abducted to minimize tension on the sac.
Monitor the sac for leakage of cerebrospinal fluid (CSF) and signs of infection, particularly meningitis.
Parents are encouraged to interact with the newborn but should avoid carrying them in a way that puts pressure on the sac.
Post-operative Care:
The infant remains in a prone or side-lying position until healing occurs, after which a supine sleep position may be introduced (making this an exception to the "back to sleep" recommendation initially).
Monitor pain, intake and output (I&O), and head circumference.
If a shunt is present, monitor for malfunction.
Range of motion exercises are initiated to prevent muscle contractures.
Provide ongoing support and information to parents.
Long-Term Management and Education:
Latex Allergy: Children with spina bifida are at an exceptionally high risk for latex allergy due to increased exposure during early medical interventions (e.g., in the NICU). Awareness of cross-reactive foods (e.g., papaya, kiwi, banana, avocado, chestnut) is important. Severe reactions require an EpiPen.
Skin Integrity: Due to potential loss of sensation in lower extremities, daily skin checks are crucial to detect injuries. Keep all skin surfaces clean and dry, and ensure protective measures like socks under braces.
Immunizations: Recommended, but parents should be aware that seizures may occur following immunizations in children with seizure disorders.
Screenings: Routine developmental and health screenings are essential, including urinalysis in the newborn period and ongoing screening for scoliosis.
Growth and Development: Monitor head circumference and developmental status. Motor skills are often delayed, necessitating early intervention while promoting independence.
Nutrition: Calorie intake and portion control are vital due to potential immobility, which increases the risk of obesity. Increased fluids and fiber help prevent urinary tract infections (UTIs) and constipation.
Intermittent Catheterization: Clean intermittent catheterization is performed on a regular schedule (e.g., every hours) for neurogenic bladder management; it is a "clean" procedure, not sterile.
Psychosocial Issues: Children and adolescents with spina bifida may face psychosocial challenges related to their condition, affecting sleep, rest, and relationships.
Plagiocephaly
Definition: A condition where a baby's head has a flatten spot on one side, often necessitating the use of a corrective helmet.
Cerebral Palsy (CP)
Definition: A group of permanent disorders of the development of movement and posture, causing activity limitations, that are attributed to non-progressive disturbances that occurred in the developing fetal or infant brain.
Associated Problems: Often accompanied by problems with hearing, vision, communication, perception, cognition, and behavior.
Nature: It is a permanent disorder causing lifelong activity limitations.
Multidisciplinary Management: Requires a comprehensive team approach, including a case manager, early intervention services, addressing financial needs, individualized education programs (IEPs), orthopedic surgeons, speech therapy, regular eye exams, a pediatrician, and support groups.
Traumatic Brain Injury (TBI)
Primary vs. Secondary Injury: TBI involves both initial damage (primary) and subsequent damage from physiological responses (secondary).
Concerns: Safety and prevention of falls are paramount.
Cushing's Triad: A classic set of signs indicating significantly increased intracranial pressure (ICP):
Bradycardia: Decreased heart rate (children should not exhibit bradycardia).
Irregular Respirations
Increased Systolic Blood Pressure with a Widened Pulse Pressure: (e.g., systolic of mmHg over a diastolic of mmHg, showing a large gap compared to a normal pulse pressure of mmHg).
Emergency Care: Prioritize Airway, Breathing, and Circulation (s).
Severity: A Glasgow Coma Scale (GCS) score of or less indicates a severe brain injury.
Concussion: Characterized by a loss of consciousness following a head injury.
Spinal Cord Injury (SCI): Damage to the spinal cord results in paralysis from the point of injury downwards.
Near Drowning
Prevention: Emphasize teaching babies and children to swim.
Risk: Can occur in very shallow water (e.g., bathtubs, mop buckets) if supervision is inadequate.
Consequences: Even if revived (near drowning), the event causes cerebral edema and increased intracranial pressure. Prolonged oxygen deprivation leads to significant brain damage, meaning the individual may survive but with severe, permanent neurological deficits.