2 - Altered Mental Flashcards
Disorders of consciousness may be divided into?
Processes that affect either:
- arousal
- content of consciousness
or a combination of both
Where do the neuronal structures responsible for the content of consciousness reside?
Cerebral cortex
Content of consciousness includes___
- Self-awareness
- Reasoning
- Spatial relationship integration
- Emotions
- Complex integral processes that make us human
What is dementia?
Failure of the content of portions of consciousness with relatively preserved alerting functions
What is delirium
Arousal system dysfunction with the content of consciousness affected as well
What is a coma?
Failure of both arousal and content functions
Pts with delirium?
Notice symptoms over days with fluctuating effects
They have disordered attention and cognition with either reduced or hyperalert consciousness
Their orientation is impaired and they may have hallucinations, delusions
Their movements are asterixis and often have tremors
Chart on slide 7 if that works better
Pts with dementia?
Have an insidious onset with stable symptoms
They are alert with normal attention
Cognition and orientation are impaired
There are generally no hallucinations, delusions or movement abnormalities
Pts with psychiatric disorders?
Symptoms have a sudden onset and are stable
Pts are alert with disordered attention and impaired cognition/orientation
Hallucinations are usually auditory and delusions are sustained
Typically no movement disorders
Delirium definition?
Transient disorder with impairment of attention and cognition
Aka: Acute confusional state Acute cognitive impairment Acute encephalopathy Altered Mental status
Pathophysiology of delirium? (4 general causes)
- Primary intercranial disease
- Systemic diseases secondarily affecting the CNS
- Exogenous toxins
- Drug withdrawl
With delirium it is not unusual for?
Symptoms to be intermittent, not unusual for different caregivers to witness completely different behaviors w/in a brief timespan
Sleep wake cycle for delirium pts?
Often disrupted
- increased somnolence during day
- agitation at night/sundown
Clinical signs of delirium
Tremor Asterixis Tachycardic Sweating HTN Emotional outburst
What type of hallucinations do delirious pts have?
Usually visual but auditory is also possible
Symptoms thatre “virtually diagnostic” of delirium?
Actue onset of attention deficits and cognitive abnormalities fluctuating in severity throughout the day with worsening symptoms at night
What must be done for a diagnosis of delirium?
Tests
R/O drugs, pneumonia, UTI etc
Test electrolytes, hepatic and renal, UA, CBC and chest radiograph
Head CT
Lumbar puncture (post CT)
What are some diagnostic tools that can be used to diagnose delirium?
Mini-mental (doesnt do mild impairment)
Quick confusion scale (no reading, writing, or drawing required)
___ often resembles hypoactive delirium but can be differentiated by?
Depression
But r/o by:
- Rapid fluctuation of symptoms
- Clouding of consciousness (absent)
- Depressed pts can follow commands
Status epilepticus or complex partial status epilepticus?
Unusual cause of confusional state but may be under-recognized
Get an EEG if suspected
Tx for delirium?
Detect and treat the underlying cause
Common delirium drugs?
Haloperidol (5-10mg PO, IM, IV)
Benzodiazepines: lorazepam (0.5-2.0 PO, IM, IV)
Often combined
Common causes of delirium?
Infections
Metabolic/toxic
Neurologic
Cardio
Drugs
Slide 20 has examples of these
Almost all delirium pts get?
Admitted
Unless they have a readily reversible cause
What are the largest categories of dementia?
Idiopathic dementia
- alzheimers (#1 in US)
Vascular dementia
- diagnosis of exclusion
pathognomonic for alzheimre’s disease?
Amyloid deposition
Neurofibrillary tangles and plaques
What is the pathology of vascular dementia?
CVD with multiple infarctions
List of possible causes of dementia?
Degenerative Vascular Infectious Inflammatory Neoplastic Traumatic Toxic (etoh) Metabolic Psychiatric Hydrocephalic
(Slide 25 has examples)
Characteristic of the onset of dementia associated with Alzheimer’s?
Impaired memory and orientation
with
preserved motor and speech
Early stage of degenerative dementia?
Memory loss
Naming problems
Forgetting of items
Middle stage of degenerative dementia?
Progression of early stage \+ Loss of reading Decreased social function Loss of direction
Late stage degenerative dementia?
Early and middle \+ Extreme disorientation Inability to self care Personality changes
Pts with vascular or multi-infarct dementia show similar symptoms to degenerative but they also often have?
Exaggerated/asymmetric DTR
Gait abnormalities
Weakness of an extremity
Presence of focal neurologic signs may suggest?
Vascular dementia
Mass lesion
Increased motor tone and extrapyramidal signs (rigidity or movement disorder) indicate?
Parkinson’s
Labs and images for Dementia?
CBC CMP UA Thyroid function Serum B12 Syphilis test ESR Folate level HIV
CXR
CT/MRI
Lumbar puncture (maybe)
You cannot have a diagnosis of probably vascular dementia w/o?
Signs of CVD
Differentiating between stroke and vascular dementia?
Stroke: symptoms w/in 3 mo (temporally related)
VD: fluctuating, stepped course
Pseudo dementia?
Depression-imitating dementia
What may cause a rapid decline in a mild demented pt?
UTI
CHF
Hypothyroid
And many more similar things
All types of dementia are treatable at least to some degree by?
environmental
or
psychosocial interventions
Who should antipsychotic drugs be reserved for?
Pts with persistent psychotic features
or
those with extreme disruptive or dangerous behaviors
How is vascular dementia treated?
Tx is limited to tx of risk factors including HTN
When should you consider normal-pressure hydrocephalus?
If Urinary incontinence and gait disturbance develop early in the disease process
Your pt has excessively large ventricles on head CT, what does this suggest? What can you do about it?
Normal-pressure hydrocephalus
Consider a trial of lumbar puncture with CSF drainage or ventricular shunting
What does the ED do with dementia pts?
They r/o thing that are immediately treatable or will kill the pt then attempt to admit or arrange for an outpatient diagnosis.
ED isn’t set up to do all the in depth testing and therapy required for this diagnosis
Definition of coma?
State of reduced alertness and responsiveness from which the patient cannot be aroused
What limitations does the Glasgow coma scale have?
Doesn’t acknowledge:
- hemiparesis
- focal motor signs
Doesn’t test for
- higher cognitive function
GCS
Slide 36
If a pt is intubated how is their GCS assessed?
The verbal testing is not done and a T is written next to the score i.e. 10T
The new lowest score possible is 2T
GCS number ranges?
13-15: mild head injury
9-12: moderate head injury
= 8: sever head injury (intubate)
Common pathophysiology of coma?
Deficiency of substrates (hypoxia)
Systemic cause (global)
Primary CNS cause (hemorrhage)
Specific areas (look for CN signs)
Do strokes cause comas?
Not alone
The function of the brainstem and/or both hemispheres must be impaired for unresponsiveness to occur
Cerebral autoregulation maintains cerebral blood flow at a MAP of?
50-100mmHg
What happens when cerebral MAP is off?
Cerebral blood flow is reduced leading to diffuse ischemia
What is cerebral perfusion pressure?
Cerebral perfusion pressure = MAP - ICP
If an unresponsive pt has a hx of seizures you must consider?
Ongoing non convulsive seizures
- subtle status epileptics or ictal coma
These may continue in the absence of clinical seizures
Coma clinical features?
Widely varied:
- increased ICP -> complete loss of motor tone
- variety of abnormal breath patterns
- pupillary findings
Findings on a toxic-metabolic coma?
- lack of specific brain region findings
- movements/reflexive posturing is symmetric
- muscle stretch reflexes symmetric
- pupils are small but reactive
- extraocular moments are absent
Exception to the rules of toxic coma?
Sedative poisoning (barbiturates)
- pupils = large
- extraoccular movement absent
- muscles flaccid
- apneic (looks like brain death)
How do supratentorial lesions present?
Progressive hemipareiss Asymmetric muscle tone/ reflexes Lateralizing signs Reflex changes in BP and HR HTN Bradiacardia
Coma without lateralizing signs may result from?
Decreased cerebral perfusion secondary to increased ICP
In reality however supratentorial lesions frequently present how?
Large acute supratentorial lesios are seen w/o the features consistent with temporal lobe herniation
Signs that a coma may actually be a pseudocoma?
Normal and intact
- Pupilary responses
- EOM
- Muscle tone
- Reflexes
Avoidance of gaze
Nystagmus (strong evidence)
The posterior fossa cannot take much expansion so infratentorial lesions often cause?
Abrupt coma
Abnormal extensor posturing
Loss of pupillary reflexes
Lose of EOM
Pinpoint-sized pupils indicate?
Pontine hemorrhage
History and PE can vary greatly with coma so:
Liberal use of CT scanning is encouraged
Abrupt coma suggests?
Abrupt CNS failure
- catastrophic stroke
- seizure
Slow progressive onset coma suggests?
progressive CNS lesions
- tumor
- subdural hematoma
Also could be metabolic
- hyperglycemia
Findings that suggest CNS lesions?
Asymmetric findings of CN exam
- pupillary exam
- corneal reflexes
- oculovestibular reflex
The goal of the physician when diagnosing coma pts?
Rapidly determine if the CNS dysfunction is from
- diffuse
- focal
Focal may be treatable with surgery
Midline shift and mass lesions?
Acute hemorrhage
If CT is unremarkable and subarachnoid hemorrhage or CNS infection is suspected?
Do a lumbar puncture
“Normal” CT with hyperdense basilar artery?
Suspect basilar artery thrombosis
Get an MRI or cerebral angiography
Continuing state of electrical seizures w/o corresponding motor movements is aka?
Nonconvulsive status epileptics
Subtle status epileptics
Electromechanical dissociation of brain and body
If a seizing pt stops convulsing and doesnt wake up in 30 min?
Consider nonconvulsive status epileptics
Tx of coma?
Find and fix the problem
Maintain:
- Airway
- ventilation
- circulation
Antidotes for some coma’s?
Thiamine (before dextrose)
Dextrose
Naloxone
What drug is not recommended for routine use as a coma antidote?
Flumazenil
Elevated ICP tx?
- Paralytic/sedatives
- Elevate bed 30*
- mannitol (0.5 - 1.0 gram/kg IV)
- dexamethasone (10mg IV)
- hyperventilation (reduce PPCO2)
Recommendations for using hyperventilation in ICP pts?
Avoid excessive hyperventilation (PPCO2 /= 35 mmHg) in the 1st 24 hrs
Brief hyperventilation for refractory intracranial HTN
Haloperidol dose?
5-10mg PO, IM or IV
Reduced dosing of 1-2 for elderly
Lorazepam dose?
0.5 - 2.0mg PO, IM, IV
When combined w haloperidol does = 1-2mg
Holy Jesus! What is that? What the fuck is that? WHAT IS THAT, PRIVATE PYLE?
Sir, a jelly doughnut, sir!
Central herniation syndrome S/S?
- Progressive LOC
- loss of brainstem reflexes (vitals/pain reaction etc)
- decorticate posturing
- irregular respiration
S/S Uncal herniation syndrome
Medial temporal lobe shifts to compress the upper brainstem, resulting in
- progressive drowsiness
- followed by unresponsiveness
- Ipsilateral pupil is sluggish
- Dilated/nonreactive pupil (3rd CN compression)
Brain stem is an anchor that gets pushed the opposite direction of the swelling
