Ch. 3 - Neurologic Diagnostic Procedures
Who qualifies for ICP monitoring?
(Early identification of increased ICP) Comatose or GCS < 8
What is decerebrate posture?
Abduction of arms with extension of elbows and wrists
What is decorticate posture?
Adduction of arms with flexion of elbows and wrists
What are intraprocedural considerations for lumbar puncture?
Area of needle insertion is cleansed and local anesthetic injected Needle inserted and CSF withdrawn, needle removed Manometer can be used to determine opening pressure of spinal cord (look for increased pressure)
What are preprocedural considerations for PET/SPECT?
Assess for Hx of diabetes to avoid hyper/hypoglycemia before and after procedure
How do you interpret GCS?
Best possible score = 15 < 8 associated with severe head injury and coma 9-12 associated with moderate head injury > 13 associated with minor head traumac
What are complications of lumbar puncture?
CSF leak can cause HA and infection: Client lie flat in bed Give fluids for hydration and administer pain meds Prepare for epidural blood patch to seal hole if headache persists
What are postprocedural considerations for lumbar puncture?
CSF sent to pathology for analysis Monitor puncture site Client should remain lying for several hours to ensure that site clots and decrease risk for post-lumber puncture HA caused by CSF leak
What are intraprocedural considerations for cerebral CT?
Client must lie supine with head stabilized Although CT is painless, sedation can be used
What are intraprocedural considerations for cerebral angiography?
Client placed on radiography table and head secured Catheter placed into artery (usually groin/neck), dye injected, and x-rays taken Once done, catheter removed and arterial closure device used/pressure is held over artery to control bleeding
What are postprocedural considerations for a cerebral angiography?
Closely monitor area to ensure clotting occurs Movements are restricted depending on procedure used to seal artery to prevent rebleeding Place ice pack on insertion site
What are indications for MRI?
Detect abnormalities, monitor response to treatment, and guide needles used for biopsies Discriminates soft tissue from tumor or bone = tumor size and blood vessel location
What is intracranial pressure monitoring?
Device inserted into cranial cavity that records pressure and is connected to a monitor that shows a picture of the pressure waveforms
How do you calculate total GCS?
E + V + M = Total GCS
What are preprocedural considerations for lumbar puncture?
Educate on risks versus benefits: Can be associated with brain herniation especially if increased ICP Bleeding disorders/anticoags put at higher risk for bleeding that compresses spinal cord Ensure all jewelry removed and only wearing gown Void before procedure "Cannonball" position to stretch spinal canal while on one side
What are intraprocedural considerations for MRI?
Ensure clients remains supine with head stabilized MRI is noisy - earplugs/sedation may help
What are indications for x-ray?
Exams of skull and spine can reveal fractures, curvatures, bone erosion and discoloration, and possible soft tissue calcification = can damage nervous system
What is client education preprocedural for x-ray?
Explain amount of radiation used in contemporary x-ray machines is very small
What is the criteria for GCS?
Eye (E) opening: 4 = Spontaneously 3 = Secondary to sound 2 = Secondary to pain 1 = Does not occur Verbal (V): 5 = Conversation coherent and oriented 4 = Conversation incoherent and disoriented 3 = Words are spoke inappropriately 2 = Sounds made but no words 1 = Does not occur Motor (M): 6 = Commands are followed 5 = Location reaction to pain 4 = General withdrawal from pain 3 = Decorticate posture present 2 = Decerebrate posture present 1 = Does not occur
What are preprocedural considerations for ICP monitor?
Head is shaved around insertion location Site is cleaned with antibacterial solution
What is preprocedural client education for cerebral angiography?
Head will be immobilized during procedure, so need to stay still Void immediately before procedure Following dye injection, common to have metallic taste and feel of warmth behind eyes, over face, jaw tongue, and lips
What are the three types of ICP monitoring?
Intraventricular catheter Subarachnoid screw or bolt Epidural/subdural sensor
What are intraprocedural considerations for ICP monitor?
Local anesthetic can be used to numb area if client's GCS indicates some LOC (8-11) Insertion and care of any ICP monitoring devices requires surgical aseptic technique to reduce risk for CNS infection
What are postprocedural considerations for ICP monitor?
Maintain system integrity at all times; system contamination can cause serious, life-threatening infection Inspect insertion site at least every 24 hrs for red, swelling, drainage Equipment must be balanced and recalibrated per protocol After insertion, observed ICP waveforms, noting pattern and monitoring for increased ICP Assess client's clinical status and monitor routine/neuro VS every hour PRN
What are indications of an EEG?
Most commonly used to identify and determine seizure activity Also used for detecting sleep disorders and behavioral changes
What are postprocedural considerations for cerebral CT?
No follow-up care needed If contrast used, monitor allergic reaction and changes in kidney function If sedation used, monitor until stable
What are preprocedural considerations for x-ray?
None if don't use contrast Determine if client is pregnant Ensure jewelry removed and no clothes cover area
What is an electroencephalography?
Noninvasive procedure that assess electrical activity of brain and is used to determine abnormalities in brain wave patterns Provides info about ability of brain to function and highlight abnormalities
How do you interpret ICP monitoring findings?
Normal ICP: 10-15 mmHg Persistent elevation of ICP minimizes cerebral circulation = can result in brain death
What is injected into the bloodstream to initiate regional metabolic activity in PET and SPECT?
PET = Glucose-based tracer SPECT = Radioisotope
What are PET /SPECT scans?
Positron emission tomography or Single-photon emission computed tomography Nuclear medicine procedures that produce 3D images of the head (static or functional)
What is a cerebral CT scan?
Provides cross-sectional images of cranial cavity Contrast medium can be used to enhance images
What is a cerebral angiography?
Provides visualization of cerebral blood vessels Digital subtraction angiography = hides bones/tissue from images providing x-rays so vessels only show Detects defects, narrowing, or obstruction of arteries or blood vessels in brain Performed within radiology because iodine-based contract dye is injected into artery
What are postprocedural considerations for PET/SPECT?
Radioisotopes used = assess for allergic reaction No follow-up care needed Glucose tracer is broken down in body as a sugar, not excreted
What are preprocedural considerations for MRI?
Remove transdermal patches with foil backing Ensure jewelry removed, only hospital gown worn Sedation = no food/fluids 4-8 hrs before Check for Hx of claustrophobia and explain tight space/noise Ask about implants containing metal (pacemakers, orthopedic joints, artificial heart valves, intrauterine devices, aneurysm clips) All people in scanning area remove jewelry, electronics, and cellphones to prevent damage Place pillows in small of back, secure head
What are preprocedural considerations for EEG?
Review meds with provider to determine if they should be continued before procedure
What are complications of a cerebral angiography?
Risk for bleeding/hematoma at entry site: Monitor insertion site frequently Check affected extremity distal to puncture for adequate circulation If bleed occurs, put pressure and call provider
What is an MRI?
Scan of the head provides cross-sectional images of cranial cavity; contrast media might be used
What is a lumbar puncture (spinal tap)?
Small amount of CSF is withdrawn from spinal canal then analyzed to determine constituents
What are indications for PET/SPECT?
Tumor activity and/or response to treatment Determine presence of dementia = no response to tracer
What are indications for lumbar puncture?
Used to detect some diseases, infection, and malignancies Reduce CSF pressure, instill contrast medium or air, or administer meds or chemo directly to spinal fluid
What an x-ray?
Uses electromagnetic radiation to capture images of internal structures of individual Image is light or dark relative to amount of radiation the tissue absorbs
What are intraprocedural considerations for an EEG?
Usually takes 45-120 mins No risks associated Client resting in chair or lying in bed = small electrodes placed on scalp and connected to brain wave machine or computer Electrical signals produced by brain are recorded by machine or computer in form of wavy lines Notations are made when stimuli are presented or when sleep occurs
What is preprocedural client education for EEG?
Wash hair to eliminate oils, gels, and sprays Stay awake prior to test Stimulate electrical activity = might be exposed to bright flashing lights or asked to hyperventilate for 3-4 mins Avoid taking any stimulant or sedative 12-24 hrs before
What are indications for a cerebral angiography?
When we need to assess blood flow to and within brain, identify aneurysms, and define vascularity of tumors Used therapeutically to inject meds to treat clots or administer chemo
What are intraprocedural considerations for PET/SPECT?
While pictures are obtained, client must lie flat with head restrained Not painful and sedation is rarely necessary
What is the Glasgow Coma Scale (GCS)?
Assessment that concentrates on neurological function and is useful to determine LOC and monitor response to treatment
What are indications for cerebral CT scan?
Identify tumors and infarctions, detect abnormalities, monitor response to treatment, and guide needles used for biopsies
What are postprocedural considerations for MRI?
If contrast used = monitor site to ensure clotting has occurred and monitor for allergic reaction If sedation used = monitor client until stable
What are preprocedural considerations for cerebral CT?
If contrast used: -No food/fluids for at least 4 hrs before -Assess for shellfish/iodine allergy -Assess BUN/creatinine for kidney function Position is supine so pillows in small of client's back to prevent back pain Head must be secured to prevent extra movement Ensure jewelry removed before procedure
What are complications of ICP monitoring?
Infection and bleeding: Surgical aseptic technique Sterile dressing changes Keep drainage systems closed Limit monitoring 3-5 days Irrigate system only as needed for patency
What is key about insertion for intracranial pressure monitoring?
Insertion is done by neurosurgeon in OR, ED, or critical care unit Rarely used unless client is comatose, so minimal need for pain meds and preprocedural client teaching
What are intraprocedural considerations for x-ray?
Procedure quick but client must stay still
What are s/s of increased ICP?
Severe headache Worsening LOC Restlessness Irritability Dilated or pinpoint pupils Slowness to react Alteration in breathing pattern Worsening motor function Abnormal posturing
With ICP monitoring, what is increased ICP?
Sustained elevation of pressure greater than 15 mmHg
What are preprocedural considerations for cerebral angiography?
Tell client to refrain from food/fluids for 4-6 hrs before Assess allergies Any Hx of bleeding or anticoags requires additional monitoring during procedure Assess BUN/creatinine to determine kidney health for excreting contrast dye Ensure client is not wearing jewelry Mild sedative for relaxation is occasionally used
