Term
| What age group has the highest incidence of head injuries? |
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Definition
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Term
| What is the second highest most common age group for Head injuries? |
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Definition
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Term
| The ratio of occurrence of head injury men: women is.... |
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Definition
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Term
| What are common etiologies of head injuries? |
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Definition
*Falls
*Motor vehicle accidents (leading cause of HI in young)
*Struck by/against
*Assaults
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Term
| How often is ETOH involved in head injury? |
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Definition
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Term
| What four terms are used to classify head injury? |
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Definition
*Penetrating vs. closed
*Primary vs. Secondary |
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Term
| When does primary head injury occur? |
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Definition
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Term
| How does damage occur in primary head injury? |
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Definition
*Results directly from the disruption of intracranial structures
*Due to the biomechanical forces applied to the cranium and brain |
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Term
| What are some common causes of primary head injury? |
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Definition
*Concussion
*Fracture
*Hematoma
*Contusion |
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Term
| How does secondary head injury result? |
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Definition
*Injury resulting from the initial trauma
*Secondary deterioration |
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Term
| List some secondary head injury contributing factors: |
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Definition
*Hypoxia
*Hypercarbia
*Hypotension
*Intracranial HTN
*Ischemia
*Hyperglycemia
*Vasospasm
*Anemia
*Acidosis
*Extreme Hypocarbia
*Seizures
*Hyperthermia |
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Term
| What five factors have been associated with poor outcome in relation to head injury? |
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Definition
*60 years of age or more
*Initial GCS of <5
*A fixed, dilated pupil
*Prolonged hypotension or hypoxia
*Presence of a mass lesion requiring operative intervention |
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Term
| What are the most important factors that contribute to Morbidity and mortality? |
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Definition
*Hypoxemia PaO2 <60
*Hypotension SBP <90
*70% of hypotensive pts have significant M&M
*90% with both have significant M&M |
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Term
| What information should be ascertained in a neurologic assessment after an injury? |
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Definition
*History
*Type of injury
*Course of events since injury
*Any seizure, LOC, apnea?
*Signs of increased ICP
*Any known medical history
*Think AMPLE
Allergies
Meds
Past illness
Last meal
Events related to injury (what happened?) |
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Term
| What scale is used to measure neurological status? |
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Definition
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Term
| What are the 3 elements of the GCS and what is the top and lowest scores possible? |
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Definition
*Best eye opening (4)
*Best verbal response (5)
*Best motor response (6)
*3 is lowest
*15 is highest |
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Term
| How can pupillary changes be used? |
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Definition
| *Pupillary changes are useful predictors of outcome |
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Term
| Bilateral dilated pupils on admit predict.... |
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Definition
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Term
| Bilateral constricted pupils on admit predict.... |
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Definition
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Term
| Normal pupils on admit indicate..... |
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Definition
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Term
| What presentation of vital signs are expected with head injury? |
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Definition
*Hypotension
*HTN and Bradycardia
*Hpotension and Bradycardia (think spine injury) |
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Term
| What neurologic exams should be measured first? |
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Definition
*LOC and mental status first
*Cranial nerve exam to assess brainstem |
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Term
| What type of movement is seen if the injury is at the cortical level? |
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Definition
*Decorticate movement
*Flexion of UEs and hyperextension of the LE |
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Term
| When injury extends to the midbrain what type of posturing occurs? |
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Definition
*Decerebrate posture
*Hyperextension of both the UE and LE |
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Term
| When injury involves the pons what occurs? |
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Definition
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Term
| What is the goal of initial management of the head injured patient? |
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Definition
| *Minimize the occurrence of secondary injury |
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Term
| How is secondary injury minimized? |
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Definition
*Control hypoxia, hypotension, hypercarbia, intracranial HTN
*Prevent cerebral ischemia
*Maintain cerebral perfusion |
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Term
| Patients with a GCS < ____ should be intubated early and mechanically ventilated. |
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Definition
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Term
| What are some things to consider to ensure a patent airway? |
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Definition
*Clean out oral cavity
*insert OPA/NPA if needed and not contraindicated
*Do not hyperextend the neck
*Careful assessment before intubation |
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Term
| What should be assumed when intubating a patient with a head injury? |
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Definition
*Assume cervical spine injury is present (1-3% of CHI pts have c-spine fracture)
*Assume Full Stomach
*Assume an increased ICP is present
**How urgent is the need for intubation?
*Denitrogenate, ventilate by mask until ready
*Must have suction and O2 ready
*Assess the extent of facial fractures and soft tissue edema. |
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Term
| For the patients without a difficult airway, the simplest, safest route for intubation is.... |
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Definition
| *Asleep rapid sequence with preoxygenation |
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Term
| How should the patient be intubated? What precautions should be taken in the head injured patient? |
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Definition
*Do not manipulate the neck, keep in neutral position
*Manual inline stabilization
*Cricoid pressure? Controversial
*Decompress stomach afterward
*Severe facial fractures, basilar skull fracture or profuse bleeding may C/I nasal intubation
*Consider fiberoptic, criocothyroidectomy or tracheostomy depending upon the type of injuries, amount of time available and the characteristics of the airway. |
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Term
| True or False: Head injury is rarely the cause of sustained hypotension. |
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Definition
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Term
| How should a head injured patient be cardiovascularly managed? |
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Definition
*Preservation of an adequate CPP
*Restore volume status with isotonic crystalloid or colloid. NO DEXTROSE
*Keep hematocrit @ 30% to maximize O2 transport and cerebral perfusion
*Injured brain releases thromboplastin & cause coagulopathy--> DIC. |
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Term
| How can increases in ICP be avoided in the patient with a head injury |
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Definition
*ICP >20mmHg demands aggressive treatment
*Elevate HOB 20-30 degrees (must be euvolemic)
*Head midline
*Hyperventilation used selectively
*Maintain normal BP
*Avoid coughing, straining, any acute rise in ICP
*Diuresis
*Seizure prophylaxis |
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Term
| How is a head injury diagnosed? |
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Definition
*CT SCAN
*Reveals the size and location of the lesion
*Degree of midline shift (>5mm shift, indicative of increased ICP)
*Presence of edema |
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Term
| What risk is present with depressed and basilar skull fractures? |
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Definition
*Risk of infection
*Depressed fractures to OR for early debridement |
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Term
| What is the definition of a depressed skull fracture? |
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Definition
| *A bony segment of the skull sunk below the normal thickness of the skull. |
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Term
| What is the clinical significance of a depressed skull fracture? |
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Definition
| *Fragments may tamponade a damaged vessel. |
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Term
| What type of fractures are commonly depressed skull fractures? |
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Definition
*Open fractures
*Fractures over dural sinus
*Dural tears
*Cortical injury |
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Term
| What are anesthetic considerations for the patient with a depressed skull fracture? |
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Definition
*Evaluate the patient
*1 or 2 large bore IVs
*Arterial line probably not necessary
*Foley useful
*With dural sinus laceration, prepare for blood loss |
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Term
| What are signs of a basilar skull fracture? |
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Definition
*Rhinorrhea
*Otorrhea
*hemotympanum
*Battle's sign (ecchymosis over mastoid area)
*Raccoon Eyes (periorbital ecchymosis)
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Term
| What are important considerations for basilar skull fractures? |
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Definition
*Most resolve spontaneously
*Important to be aware of because nasal intubation is relatively CONTRAINDICATED.
*Can pass NET tip into cranium and infect CSF
*If OET is impossible, decide what is best, NET, trach or a cricothyrotomy. |
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Term
| How do epidural hematomas typically occur? |
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Definition
*Disruption of the middle meningeal artery or its branches often d/t temporal bone fracture
*75-90% are accompanied by skull fracture |
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Term
| Epidural hematomas resulting from arterial bleeding are often..... |
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Definition
| *A true neurosurgical emergency, may enlarge quickly. |
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Term
| What do epidural hematomas usually result from? |
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Definition
*Disruption of the middle meningeal artery or its branches often due to a temporal bone fracture.
*75-90% are accompanied by a skull fracture |
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Term
| What is the classical presentation of an epidural hematoma? |
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Definition
*Initial transient LOC followed by a lucid interval.
*Often normal neuro exam when lucid
*Lacerated vessel clots or spasms.
*H/A begins as hematoma enlarges, LOC decreases and signs of increasing ICP occur.
*As impending herniation nears, dilation for ipsilateral pupil and contralateral extremity weakness may occur w/ decerebrate positioning. |
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Term
| What is the mortality rate if coma occurs in epidural hematoma? |
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Definition
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Term
Patients with an epidural hematoma are often ____________ masked by HTN or normotension.
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Definition
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Term
| What occurs when an epidural hematoma is surgically decompressed? |
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Definition
*ICP is rapidly reduced
*The driving force causing HTN is removed
*Blood pressure decreases
*Adjust anesthesia and be aware of when the clot is being removed! |
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Term
| What should be available for the surgical evacuation of an epidural hematoma? |
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Definition
*Arterial line
*2 large bore IVs
*2-4 units PRBC |
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Term
| How should the anesthetist manage evacuation of an epidural hematoma? |
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Definition
*Titrate anesthetics carefully
*May hyperventilate
*Be aware of when clot removal occurs.
*Do not delay surgical intervention for line placement
*Expand volume using isotonic crystalloids and blood products. |
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Term
| What are common causes for subdural hematomas? |
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Definition
*Acceleration-deceleration injury--> stretching and damage to parasagittal bridging veins
*Can occur spontaneously d/t aneurysm, neoplasm, or coagulopathy. |
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Term
| What are three types of subdural hematomas? |
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Definition
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Term
| In what time frame do acute subdural hematomas occur? |
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Definition
| *Within 72 hours of injury |
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Term
| What is the mortality of an acute subdural hematoma and what implications does treatment delay >4 cause? |
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Definition
*Mortality 40-70%
*If >4 hour treatment delay Mortality rises to 80-90%. |
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Term
| What happens to the brain after an acute subdural hematoma? |
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Definition
*Severe brain injury
*Acute brain swelling |
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Term
| What is the treatment of a subdural hematoma? How can Acute brain swelling compromise this? |
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Definition
*Craniotomy & Clot removal
*Often stay intubated
*ICP monitored post-op
*Acute brain swelling may complicate closure after SDH evacuated. |
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Term
| What is the anesthetic management of an acute SDH? |
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Definition
*If arterial bleed is expected:
*Need 2 large bore IVs
*4u PRBCs
*A-line |
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Term
| In what time frame do subacute SDH occur? How do the outcomes compare to acute SDH? |
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Definition
*3-15 days post injury
*Often better d/t not severe diffuse brain injury with swelling. |
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Term
| In what time frame do chronic SDH occur? |
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Definition
*May be >2 weeks post injury.
*Develop slowly until symptomatic
*May be no history of trauma |
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Term
| In what type of patients do chronic subdural hematomas occur in? |
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Definition
*Patients >50yrs, alcoholics, epileptics, bleeding disorders.
*The brain is often atrophied and there is room for clot accumulation |
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Term
| How are chronic subdural hematomas treated? |
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Definition
*Clinical signs variable
*Often ICP is not elevated
*Craniotomy or trephination
*Should be well hydrated
*Individualize plan
*Foley required |
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Term
| What is a diffuse axonal injury? |
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Definition
| *Shearing injury that tears into the cerebral substance and causes hemorrhage into the white matter. Destroys axons. |
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Term
| What is the most common cause of vegetative state and severe disability after blunt trauma? |
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Definition
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Term
| How do diffuse axonal injuries occur? |
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Definition
*Injury occurs immediately upon impact
*Severe rotation or deceleration injuries, GSWs, HTN bleed, brain tumor, or abscess.
*Immediate bleed with tissue damage from severe high pressure wave causing devastating bleed on impact.
*Similar injury is intracerebral hematoma
*May be a slower hemorrhage, occurring up to 2 weeks after admission to the hospital.
*80% occur w/in 48 hours. Mortality can be up to 40%. |
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Term
| What is the treatment for diffuse axonal injury? |
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Definition
*May not be operable
*Large, localized lesions producing symptoms should be evacuated.
*Small or deep-seated lesions are not operated on
*Treat as if patient has increased ICP. |
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Term
| Why are trephination or burr holes done? |
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Definition
*Procedure to rapidly decompress deteriorating brain
*Evacuate hematoma, drain ventricle or biopsy. |
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Term
| How are burr holes created? What type of anesthesia may be used in the appropriate patient? |
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Definition
*Small hole drilled through skull to the epidural space, the subdural space or thru the meninges to reach the ventricles.
*Cranium removed by using twist drill.
*May use local with IV sedation in the appropriate patient. |
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Term
| What is the preoperative anesthetic management for burr holes? |
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Definition
*Prevent secondary injury
*Rapid assessment (Airway, CV, Neuro, volume status)
*Check IV access
*PMH
*Blood available?
*Premedication not preferred- if combative sedate and oxygenate |
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Term
| What is the anesthetic management induction for burr holes? |
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Definition
*A-line w/ abgs
*Avoid swings in BP and HR with induction
*Keep CPP >70
*Augment volume status
*RSI- lidocaine, narcotics, BB. Pretreat or prime.
*Prop, Pent or Etomidate
*Succ the best for RSI NDMRs are accepatble
*Secure ETT out of surgical field
*Secure all other lines and monitors prior to prep |
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Term
| What is the anesthetic management during maintenance for burr holes? |
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Definition
*Adequate anesthesia before pin-type head holder if used.
*Keep deeply paralyzed
*Use Forane
*Ask surgeon about BP and Hypervent
*If brain is very swollen and not responsive to measures to decrease ICP, d/c inhalational agent and use TIVA.
*Pentothol dose: 5-25mg/kg over 5-10 min. Infusion 4-10mg/kg/hr.
*May need inotrope for BP support
*Avoid hyperthermia
*Check coags
*Administer adequate volume
*Maintain hemodynamics
*NO Dextrose or hypoosmolar
*Some advocate hypertonic or ffp/hespan |
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Term
| What is the anesthetic management during emergence for burr holes? |
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Definition
*Watch ETT during dressing application
*Communicate with surgeon: extubate or keep intubated.
*Consider keeping intubated if: multiple trauma victim, decreased LOC preop, hypothermic.
*If keeping intubated keep deep for transport, keep paralyzed, monitor during transport and elevate HOB.
*If extubating take your time, control ICP and BP- labatelol is helpful. |
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Term
| What are common cardiopulmonary sequelae after HI? |
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Definition
*Often attributable to sympathetic hyperactivity
*Increase in HR, BP, CO, VO2, shunt, V/Q mismatch, decreased SVR
*Cardiac dysrhythmias and EKG changes
*Prone to aspiration atelectasis, pneumonia, ARDS. |
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Term
| What sequelae of HI is relatively rare and results from massive sympathetic outflow after injury? |
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Definition
*Neurogenic Pulmonary Edema
*Causes increased pulmonary venous pressure & cap permeability.
*Very rapid intraalveolar hemorrhage and Pulmonary edema. |
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Term
| What are S&S of neurogenic Pulmonary edema? |
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Definition
| *Cyanosis, diaphoresis, pallor, dyspnea, weak pulse, tachycardia, pink, frothy sputum. |
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Term
| How is Neurogenic Pulmonary edema treated? |
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Definition
*Usually associated with an acute rise in ICP?
*May not respond to conventional treatment.
*Treatment: reduction of ICP, block of sympathetic hyperactivity, support the pulmonary system. |
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Term
| What is released after brain tissue damage and what can this result in? |
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Definition
*Thromboplastin is released
*Causes accelerated fibrinolysis and possible DIC.
*High mortality |
|
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Term
| What metabolic derangements occur after HI? |
|
Definition
*Diabetes insipidus
*SIADH |
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Term
| What are the S&S of Diabetes Insipidus and how is it treated? |
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Definition
*Polyuria (>3L/day)
*Polydipsia
*Hypernatremia
*High serum OSM
Treatment: Water replacement. NO Na+, Vasopressin |
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Term
| What are the S&S of SIADH and what is the treatment? |
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Definition
*Usually begins 3-15 days after trauma lasting for 10-15 days.
*Signs: water intoxication, hyponatremia, low serum OSM, renal Na+ excretion, urine osm >serum osm, N/V, irritability, personality changes.
*Treatment: Water restriction. Hypertonic saline, possibly a diuretic. |
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Term
| What complications can result from HI? |
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Definition
*Focal neurologic deficits
*Hydrocephalus
*Seizures
*CSF Fistulae
*Vascular injuries
*Infection
*Brain Death |
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