SMELTZER 61-B Neurological Dysfunction

A nurse is caring for a client in a coma who has suffered a closed head injury. What intervention should the nurse implement to prevent increases in intracranial pressure (ICP)? You selected: Turn the client and change his position every 2 hours. Incorrect Correct response: Elevate the head of the bed __ to 30 degrees. Explanation: To facilitate venous drainage and avoid jugular compression, the nurse should elevate the head of the bed 15 to 30 degrees. Clients with increased ICP poorly tolerate suctioning and shouldn't be suctioned on a regular basis. Turning the client from side to side increases the risk of jugular compression and rises in ICP, so turning and changing positions should be avoided. The room should be kept quiet and dimly lit.

15

(see full question) A client with a traumatic brain injury has developed increased intracranial pressure resulting in dibetes insipidus. While assessing the client, the nurse expects which of the following findings? You selected: Excessive urine output and serum hypo-osmolarity Incorrect Correct response: Excessive urine output and decreased urine osmolality Explanation: Diabetes insipidus is the result of decreased secretion of antidiuretic hormone (____). The client has excessive urine output, decreased urine osmolatity, and serum hyperosmolarity.

ADH

Nursing Process and Increased ICP: ICP; Deficient Fluid Volume related to fluid restriction; Risk for Infection related to ICP monitoring system (fiberoptic or intraventricular catheter).

Collaborative Problems/Potential Complications: Include brain stem herniation, diabetes insipidus, and SIADH. Planning and Goals: Airway, Normalization of Respiration, Adequate Cerebral Tissue Perfusion through reduction in ICP.

Controlling Fever: Preventing a temperature elevation is critical because fever increases cerebral metabolism and the rate at which cerebral edema forms. Strategies to reduce body temperature include administration of ANTIPYRETIC med

Controlling Fever:and use of a hypthermia blanket. Temperature is monitored closely and the patient is observed for shivering which should be avoided because it is associated with increased oxygen consumption, increased levels of oxygen consumption, increased levels of circulating

Decreasing Cerebral Edema: Another method for decreasing cerebral edema is fluid restriction. Leads to dehydration and hemoconcentration which draws fluid across the osmotic gradient and decreases cerebral edema.

Decreasing Cerebral Edema: Conversely, overhydration of the pt with increased ICP is avoided because it increases cerebral edema. Theory is that lowering body temperature would decrease cerebral edema by reducing the oxygen and metabolic requirements of the brain

Decreasing Cerebral Edema: Osmotic diuretics such as MANNITOL may be administered to dehydrate the brain tissue and reduce cerebral edema.

Decreasing Cerebral Edema: They act by drawing water across intact membranes, thereby reducing the volume of the brain and extracellular fluid.

Decreasing Cerebral Edema: Indwelling urinary catheter usually inserted to monitor urinary output and to manage the resulting diuresis. If the pt is receiving osmotic diuretics

Decreasing Cerebral Edema: serum osmolality should be decreased to assess hydration status. If a brain tumor is cause of increased ICP, corticosteroids such as DEXAMETHASONE help reduce the edema surrounding tumor.

Subarachnoid Screw or Bolt or Holllow Screw Technique: Abnormal pressure waves trigger an alarm system. Disadvantage is the inability to withdraw CSF for analysis.

Fiberoptic monitor or Transducer-tipped Catheter: An alternative to other intraventricular, subarachnoid, and subdural systems. Minature transducer reflects pressure changes which are converted to electrical signals and displayed on

Interpreting Intracranial Pressure Waveforms: reflecting cerebral ischemia and brain damage that can occur before overt signs and symptoms of raised ICP are seen. B waves are shorter (30 seconds to 2 minutes) and have smaller amplitutude (up to 50mm Hg).

Interpreting Intracranial Pressure Waveforms: B waves are less significant but if seen in a series in a pt with depressed consciousness, they may precede the appearance of A waves. B waves may be seen in pts with intracranial hypertension and decreased intracranial compliance.

Maintaining Cerebral Perfusion: Cardiac output may be manipulated to provide adequate perfusion to the brain. Improvements in cardiac output are made using fluid volume and inotropic agents

Maintaining Cerebral Perfusion: such as DOBUTREX or DOBUTAMINE and NOREPINEPHRINE or LEVOPHED. The effectiveness of the cardiac output is reflected in CPP, which is maintained at greater than 70mm.

Maintaining Oxygenation and Reducing Metabolic Demands: brain is uncertain but the resulting comatose state is thought to reduce metabolic requirements of the brain, thus providing cerebral protection.

Maintaining Oxygenation and Reducing Metabolic Demands: Another method of reducing cellular metabolic demand and improving oxygenation is the administration of PARALYSING MEDS such as PROPOFOL or Diprivan. The pt who receives

Controlling Fever: CATECHOLAMINES and increased vasoconstriction. Maintaining Oxygenation and Reducing Metabolic Demands: Arterial Blood gases and pulse oximetryu are monitored to ensure that systemic oxygenation optimal.

Maintaining Oxygenation and Reducing Metabolic Demands: Metabolic demands may be reduced through the administration of high doses of BARBITUATES if the pt is unresponsive to conventional treatment. The mechanism by which BARBITUATES decrease ICP and protect the

Maintaining Oxygenation and Reducing Metabolic Demands: and the pt's response to ventilator therapy. The level of pharmacologic analysis is adjusted based on serum levels of the meds administered.

Maintaining Oxygenation and Reducing Metabolic Demands: and the assessed parameters. Potential complications include hypotension caused by decreased sympathetic tone and myocardial depression.

Nursing Process and Increased ICP: assessment of CN, vital signs, ICP, and use of Glasgow Coma Scale. Nursing Diagnoses: Include Ineffective Airwary Clearance Related to Dimished Protective

Nursing Diagnoses: Reflexes (cough, gag) Ineffective Breathing Patterns related to Neurologic Dysfunction (brain stem compression, structural displacement) Ineffective cerebral tissue perfusion related to the effects of increased

Nursing Interventions: If hyperventilation therapy is deemed appropriate to reduce ICP by causing cerebral vasoconstriction and a decrease in cerebral blood volume.

Nursing Interventions: Collaboration with respiratory therapist in monitoring PaCO2 which is usually maintained at less than 30mmHg. A neurologic observation record is maintained.

Interpreting Intracranil Pressure: C waves are small, rhythmic oscillations with frequencies of approximately 6 per minute. They appear to be related to the rhythmic variations of the systemic arterial blood pressure and respirations. Significance of C waves not known.

Other Neurologic Monitoring Systems: Additional trends in neurologic monitoring include MICRODIALYSIS of the pt with a brain injury. Cortical probes are placed near the injured area and are used to measure levels of glutamate, lactate, and pyruvate and glucose.

Other Neurologic Monitoring Systems:These substances reflect the metabolic function of the brain. Theory is that direct measurments of glucose and energy byproducts in the brain will lead to a better management of these pts and ultimately improve outcomes.

Other Neurologic Monitoring Systems: An additional trend is monitoring of cerebral oxygen through monitoring of oxygen saturation in the jugular venous bulb (SjvO2) or via a catheter in the brain. Cerebral oxygenation is thought to be important

Maintaining Cerebral Perfusion: A lower CPP indicates that the cardiac output is insufficient to maintain adequate cerebral perfusion SjvO2 and LICOX assist in monitoring cerebral perfusion.

Reducing Cerebrospinal Fluid and Intracranial Blood Volume: CSF drainage is frequently performed because the removal of CSF with a ventriculostomy drain can dramatically reduce ICP and restore CPP, calculated by subtracting the intracranial pressure from the mean systemic arterial blood pressure..

Subarachnoid Screw or Bolt or Holllow Screw Technique: Complications include infection, blockage of the screw by clot or brain tissue, which leads to a loss of pressure tracing and a decrease in accuracy at high ICP readings.

Subarachnoid Screw or Bolt or Holllow Screw Technique:Epidural monitor: uses a pneumatic flow sensor to detect ICP. The epidural ICP monitoring system has a low incidence of infection and complications. Appears to read pressures accurately. Calibration of the system maintained automatically.

Subarachnoid Screw or Bolt or Hollow Screw Technique: is a hollow device that is inserted through the skull and dura mater into the cranial subarachnoid space . Does not require ventricular venipuncture. Subarachnoid screw is attached to a pressure transducer.

Subarachnoid Screw or Bolt or Hollow Screw Technique: The output is recorded on the oscilloscope. Also has the advantage of avoiding complications from brain shift and small ventricular size.

Ventriculostomy or Ventricular catheter: Continuous draingage of CSF under pressure control is an effective method of treating intracranial hypertension. Another advantage is access for the intraventricular administration of meds and occaisional installation of air or a contrast agent for ventriculography.

Ventriculostomy or Ventricular catheter: Complications include infection, mennigits, ventricular collapse, occlusion of the brain tissue or blood and problems with the monitoring system.

Ventriculostomy- When used, a fine bore catheter is inserted into a lateral ventricle, preferably in the nondominant hemisphere of the brain. The catheter is connected by a fluid-filled system to a transducer, which records the pressure in the form of an electrical impulse.

Ventriculostomy-To obtain continuous ICP recordings, the ventricular catheter or ventriculostomy allows the CSF to drain especially during acute increases in pressure. The ventriculostomy can also be used to drain the blood from the ventricle

The nurse is aware that burr holes may be used in neurosurgical procedures. Which of the following is a reason why a neurosurgeon may choose to create a burr hole in a patient? You selected: Visualization of a hemorrhage Incorrect Correct response: Aspiration of a brain abscess Explanation: Burr holes may be used in neurosurgical procedures to make a bone flap in the skull, to aspirate a brain ab____, or to evacuate a hematoma.

abcess

Monitoring Intracranial Pressure and Cerebral Oxygenation: Purpose of ICT monitoring is to identify increased pressure before cerebral dam___ occurs, to quantify the degree of elevation, to start appropriate treatment, to provide access to CSF for sampling and appropriate drainage, and to evaluate treatment effectiveness.

cerebral damage

Med Management- Increased ICP is an emergency. Invasive monitoring important, decrease cerebral ed____, lower the volume of CSF or decrease cerebral blood volume while maintaining cerebral perfusion. To this end, administer osmotic diuretics, restrict fluids, drain CSF, control fever, maintain systemic BP and oxygenation, and reduce cellular metabolic demands.

edema

Monitoring ICP Devices: Intraventricular Catheter(Ventriculostomy), a subarachnoid bolt, an epidural or subd___ catheter, or a fiberoptic transducer tipped catheter placed in the subdural space or in the ventricle.

subdural

Interpreting Intracranial Pressure Waveforms: The plateau waves or A waves are transient, paroxysmal, recurring elevations of ICP that may last 5 to 20 minutes and range in amplitude from 50 to 100 mm Hg.

Interpreting Intracranial Pressure Waveforms: Plateau waves are clinically significant in that they indicate changes in vascular volume within the intracranial compartment that are beginning to compromise cerebral perfusion. A waves may increase in amplitude and frequency, reflecting

Collaborative Problems/Potential Complications: Restoration of Fluid Balance, Absence of Infection, and Absence of Complications.

Nursing Interventions: Maintaining a Patent Airway: Assess airway. Secretions that obstruct the airway must be suctioned carefully. Hypoxia caused by poor oxygenation leads to cerebral ischemia and edema.

Nursing Interventions: The Valsalva Maneuver which can be produced by straining at defecation or even moving in bed raises ICP so should be avoided.

Nursing Interventions: Stool softeners prescribed. If the pt is alert and able to eat, a high fiber diet may be indicated. Abdomninal distention, which increases intra-abdominal and intrathoracic, should be noted. Enemas and cathartics should

Nursing Interventions: All observations are made in relation to the pt's baseline condition. Repeated assessments of the pt are made (sometimes minute by minute) so that improvement or

Nursing Interventions: deterioration may be noted immediately. If deterioration, preparation for surgery. OPTIMIZING CEREBRAL TISSUE PERFUSION: Reduce ICP by proper positioning. Pt's head is kept in a neutral midline position maintained with the use of a cervical collar if

Cheyne-Stokes respiration breathing with rhythmic waxing and waning of depth of breaths and regularly recurring apneic periods versus Hyperventilation or deep rapid breathing

Nursing Interventions:Achieving an Adequate Breathing Pattern: If the lower portion of the brainstem (the pons and medulla) is involved respirations become irregular and eventually stop.

Nursing Interventions: Maintaining a Patent Airway: Coughing is encouraged because it increases ICP. Lung fields auscultated at least every 8 hours to determine adventitious sounds or congestion. Elevating the head of the bed may aid in clearing secretions and improve venous drainage of the brain.

Nursing Interventions:Achieving an Adequate Breathing Pattern: Must be monitored constantly for respiratory irregularities. Increased pressure on the frontal lobes or deep midline structures may result in Cheyne-Stokes respirations whereas pressure in the midbrain can cause hyperventilation.

For a client with suspected increased intracranial pressure (ICP), an appropriate respiratory goal is to: You selected: maintain partial pressure of arterial oxygen (PaO2) above 80 mm Hg. Incorrect Correct response: promote carbon dioxide elim______. Explanation: The goal of treatment for ICP is to prevent acidemia by eliminating carbon dioxide because an acid environment in the brain causes cerebral vessels to dilate and therefore increases ICP. Preventing respiratory alkalosis and lowering arterial pH may bring about acidosis, an undesirable condition in this client. It isn't necessary to maintain a PaO2 as high as 80 mm Hg; 60 mm Hg will adequately oxygenate most clients.

elimination

Decreasing Cerebral Edema: thus protecting the brain from continued ischemia. If body metabolism can be lowered by reducing the temperature, the collateral circulation in the brain may

Decreasing Cerebral Edema:be able to provide an adequate blood supply to the brain. The effect of hypothermia on ICP not proven yet. Inducing and maintaining hypothermia requires knowledge and skill. Type and length of rewarming techniques after hypothermia may alter outcome.

Fiberoptic monitor or Transducer-tipped Catheter: a digital monitor. The catheter can be inserted into the ventricle, subarachnoid space, subdural space, or brain parenchyma or under a bone flap. If inserted into the ventricle, can also be used with a CSF drainage device.

Interpreting Intracranial Pressure Waveforms: Waves of high pressure and troughs of relatively normal pressure indicate changes in ICP. Waveforms are captured and recorded on an oscilloscope. These waves have been classified as A waves or plateau waves, B and C waves.

Maintaining Oxygenation and Reducing Metabolic Demands: PENTOTHAL and PROPOFOL. If BARBITUATES OR PARALYSING AGENTS are used, the ability to perform serial neurologic

Maintaining Oxygenation and Reducing Metabolic Demands: assessments is lost. So other monitoring tools are needed to assess the pt's status and response to therapy. Factors to be assessed include: ICP, BP, HR, Respiration rate

Maintaining Oxygenation and Reducing Metabolic Demands:these agents can't move. This decreases the metabolic demands and results in a decrease in cerebral oxygen demand. Paralysing

Maintaining Oxygenation and Reducing Metabolic Demands:agents do not produce either sedation or analgesia, which must be provided because the patient can't respond to or report pain. Most used for BARBITUATE or PARALYSING agent is PENTOBARBITOL or NEMBUTAL or

Maintaining Oxygenation and Reducing Metabolic Demands: Pts receiving high doses of barbituates or pharmacologic paralysing agents require continuous cardiac monitoring, endotracheal intubation, mechanical ventilation, and

Maintaining Oxygenation and Reducing Metabolic Demands:arterial pressure monitoring as well as ICP monitoring. Serum barbituate levels must also be routinely monitored. Nursing Process and Increased ICP:

Nursing Interventions: Elevation of the head 30 to 45 degrees unless otherwise indicated. Extreme rotation or flexion of the neck is avoided because compression or distortion of the jugular veins increases ICP.

Nursing Interventions:Extreme hip flexion avoided as intrabdominal and intrathoracic increase ICP. Rotating beds, turning sheets, and holding the pts head may minimize stimuli that increase ICP.

Nursing Process and Increased ICP: present and pertinent past med history must be taken. Must obtain information from family and friends. Neurologic exam must be as complete as pt's condition will allow.

Nursing Process and Increased ICP: LOC, CN function, cerebellar function (balance and coordination), reflexes, and motor and sensory function. Ongoing assessment more focused due to critical illness. Includes pupil checks,

Other Neurologic Monitoring Systems: Cerebral oxygenation is thought to be important because changes in cerebral perfusion may reflect an increase in ICP.

Other Neurologic Monitoring Systems: because changes in cerebral perfusion may reflect an increase in ICP.Readings taken from a catheter residing in the jugular outflow tract allow for a comparison of arterial and venous oxygen saturation

Other Neurologic Monitoring Systems:overall perfusion of the brain rather than that of a specific injured area. Another method of measuring cerebral oxygenation and temperature is by

Other Neurologic Monitoring Systems: inserting a fiberoptic catheter into the brain matter. The most common system, LICOX includes a monitor with a screen for the display of oxygen and temperature values and cables that connect to the monitoring probes in the brain.

Other Neurologic Monitoring Systems: and the balance of cerebral oxygen supply and demand is demonstrated. Venous jugular desaturations can reflect early cerebral ischemia, signaling an increase in ICP

Other Neurologic Monitoring Systems: will occur. Minimizing cerebral desaturations will improve outcomes. Now widely available and successful in identification of secondary brain insults. A limiting factor is that this saturation reflects

Reducing Cerebrospinal Fluid and Intracranial Blood Volume: Caution should be used in draining CSF because excessive CSF drainage may result in collapse of the ventricles and herniation.

Reducing Cerebrospinal Fluid and Intracranial Blood Volume:The reduction in PaCO2 may result in hypoxia, ischemia, and increase in cerebral lactate levels. Maintaining PaCO2 at greater than 30mm may prove beneficial.

A client with a traumatic brain injury has already displayed early signs of increasing intracranial pressure (ICP). Which of the following would be considered late signs of increasing ICP? You selected: Complaints of headache and lack of pupillary response Incorrect Correct response: Decerebrate posturing and loss of corneal reflex Explanation: Early indications of increasing ICP include disorien_____, restlessness, increased respiratory effort, mental confusion, pupillary changes, weakness on onside of the body or in one extremity, and constant, worsening headache. Later indications of increasing ICP include decreasing level of consciousness until client is comatose, decreased or erratic pulse and respiratory rate, increased blood presure and temperature, widened pulse pressure, Chenyne-Stokes breathing, projectile vomiting, heimplegia or decorticate or decerebrate posturing, and loss of brain stem reflexes (pupillary, corneal, gag, and swallowing).

disorientation

Which of the following types of posturing is exhibited by abnormal flexion of the upper extremities and extension of the lower extremities? You selected: Decerebrate Incorrect Correct response: Decorticate Explanation: Decorticate posturing is an abnormal posture associated with severe brain injury, characterized by abnormal flexion of the upper extremities and extension of the lower extr_____. Decerebration is an abnormal body posture associated with a severe brain injury, characterized by extreme extension of the upper and lower extremities. Flaccidity occurs when the patient has no motor function, is limp, and lacks motor tone.

extremities

When the nurse observes that the patient has extension and external rotation of the arms and wrists and extension, plantar flexion, and internal rotation of the feet, she records the patient's posturing as which of the following? You selected: Decorticate Incorrect Correct response: Decerebrate Explanation: Decerebrate posturing is the result of lesions at the midbrain and is more ominous than decorticate posturing. The described posturing results from cerebral trauma and is not normal. The patient has no motor function, is limp, and lacks motor tone with flaccid posturing. In decorticate posturing the patient has flexion and internal rot_____ of the arms and wrists and extension, internal rotation, and plantar flexion of the feet.

rotation

A nurse is caring for a client with a brain tumor and increased intracranial pressure (ICP). Which intervention should the nurse include in the care plan to reduce ICP? You selected: Position the client with the head turned toward the side of the brain tumor. Incorrect Correct response: Administer stool softeners. Explanation: Stool softeners reduce the risk of stra_____ during a bowel movement, which can increase ICP by raising intrathoracic pressure and interfering with venous return. Coughing also increases ICP. Keeping the head in a midline position and avoiding extreme neck flexion prevents obstruction of venous outflow from the brain. Sensory stimulation and noxious stimuli can increase ICP.

straining