Acute Neurological

• Brain Injury


  Can be due to: Trauma, Tumors, Stroke, Metabolic problems, Degenerative disorders
• Brain Injury can cause


  Hypoxic, ischemic injury, Increased intracranial pressure, Cerebral edema and brain compression
• Compensatory mechanism for the brain

  1. Cerebral blood flow achieves appropriate flow to meet metabolic needs (despite changes in BP, and metabolism)

  2. Hypoxic/High PaCO2 leads to dilation of cerebral vessels (decreased O2 and and increased CO2)

  3. Hyperventilation/Low PaCO2 leads to cerebral vasoconstriction (Increased O2 and decreased CO2)

  4. Reduce increased intracranial pressure

  5. Long-term leads to tissue ischemia in the brain

  6. Hypothermia: decreased brain metabolism and can protect from ischemic injury
• Cranium has 3 elements

  Brain tissue, CSF, blood
• Increase in ICP occurs when


  Increase in blood volume (increased flow, vasodilation, accumulation from hematoma), Inflammation from injury (stroke), Increased in CSF, Occurs with space-occupying lesions
• Increased ICP


  Compression leads to ischemia and brain damage, May occur with all types of acute brain injury
• TBI


  Injuries of brain tissues sustained as a consequence of trauma
• Causes of TBI


  • Falls, sports, injuries, firearms, transportation-related trauma
• Focal TBI


  • Contusions, lacerations, hemorrhages, Occur in primary injury, Coup: Injury localized to the site of the impact to the skull, Neurological symptoms r/t area of injury, Coup-contrecoup: consequence of the brain shifting within the skull during the course of an acceleration-deceleration movement, Local injury at 2 opposite poles of the brain
• Diffuse TBI


  • Movement of the brain causes widespread neuronal damage, Occur with primary or secondary injury
• Brain Compression and Herniation


  • Protrusion of brain tissue (through an opening in the dura of the brain), Extreme high mortality, Increased ICP leads to compression of neural tissue and blood vessels, Caused by an injury that increased ICP
• Concussion


  • The most common injury of athletes and military, Symptoms: Dizziness, headache, N/V, fatigue, blurry vision, Repeated concussions can lead to long-term behavior or cognitive changes
• Contusion


  • Localized focal, bruising
• Epidural Hematoma


  • Collection of blood between dura and skull, Arterial injury leading to rapid onset of symptoms
• Subdural Hematoma


  • Collection of blood between the dura and outer layer of the arachnoid membrane, Involves bridging veins leading to the symptom onset to be slower (venous blood under less pressure), Injury disrupts veins or hemorrhage involves veins
• Ischemic Stroke


  Sudden blockage of cerebral artery leading to acute ischemia
• Thrombotic stroke


  • Atherosclerosis and hypercoagulable states, Risk reduction: decrease atherosclerosis and platelet aggregation, Patient may present with carotid bruits
• Embolic stroke


  • Cardiac source such as A Fib, Risk reduction: patients with a risk of emboli formation should be on anticoagulants
• Stroke


  Result in a localized area of brain infarction, Penumbra is the region of injured brain tissue that surrounds the ischemic infarction
• Five signs of Stroke


  • Numbness/weakness in the face, arm, or leg on 1 side, Confusion, trouble speaking/understanding, Visual disturbance (1 or 2 eyes), Dizziness, loss of balance, unsteady gait
• Stroke/Injury Sequelae


  • Hemiplegia/hemiparesis: motor on sided, paralysis, weakness, Visual Field deficits can vary - Anopsia, Sensory deficit - Agnosia, Difficulty with comprehension, integration and expression of language - Aphasia, Broca aphasia: expressive (motor) or nonfluent aphasia, Wernicke aphasia: receptive
• TIA (Transient Ischemic Attack)


  Obstructing clot is efficiently lysed by the body's endogenous fibrinolytic system before permanent damage, Warning signs of thrombotic disease and risk for stroke, Symptoms last only minutes and resolve completely without evidence of dysfunction
• Intracerebral hemorrhage


  • Occurs with severe, long-standing HTN (bleeding in the brain), Most occur in the basal ganglia or thalamus, Near the hypothalamus, If large, increased ICP can lead to herniation
• Meningitis


  Inflammation of meninges surrounding the brain and spinal cord, Bacteria enter the CNS via blood or cranial structures like ears/sinuses, skull fracture, Can be Viral (self-limiting), fungal, parasitic, Bacterial leaves residual effects, Manifestations: Fever, Toxic appearance, Vomiting, Positive Kernigs sign and Brudzinski sign, Signs of increased ICP, Treatment: If bacterial, need antibiotics
• Encephalitis


  Inflammation of the brain commonly caused by viruses, less common bacteria, fungi, parasites, Manifestations: Cerebral edema, headache, fever, confusion, convulsions, weakness and rash, signs of increased ICP, Treatment: supportive care, control cerebral edema, monitor seizures and ICP
• Seizure Disorder


  Makes certain neurons hyperactive/hypersensitive to change emitting an excessively large number of electrical discharges (short circuit), Etiology: Idiopathic
• Focal Seizures


  • Begin in a specific area of one hemisphere, May not always impair consciousness or awareness, Remain localized or may spread to other cortical areas, Repetitive non-purposeful activities such as lip smacking, grimacing, rubbing (automatisms)
• Generalized Seizures


  • Begins in both hemispheres, Motor: Tonic-Clonic (most common), Atonic: sudden loss of muscle tone leading to falling to the ground (drop seizures), Nonmotor: Absence: generalized nonconvulsive with disturbance in consciousness, More common in childhood where they either stop or become tonic-clonic seizures
• Status Epilepticus


  • More than 20 minutes leading to hypoxia, Life-threatening, Series of seizures without a period of recovery between, Irreversible brain damage and possible death
• Aura/Prodrome


  Subjective sense of an impending seizure, Prodromal period is characterized by: Headache, lethargy, mood alterations, palpitations, epigastric sensations, An Aura is the beginning of the seizure, Types of aura are clues as to the location of the epileptogenic focus
• Seizure Treatment


  Protect the airway and from injury, Prevent triggers, Medications