COMA AND RELATED DO Flashcards
denotes an inability to think with customary speed, clarity,
and coherence
CONFUSION
This state also
implies a degree of imperceptiveness and distractibility,
referred to traditionally as _______
“clouding of the sensorium
A confusional state can also accompany focal cerebral
disease in various locations, particularly in the__________ or result from disorders that disturb mainly
language, memory, or visuospatial orientation
right
hemisphere,
the temporary storage of the solution of
one task for use in the next.
“working memory
next. A deficit in working memory,
which is such a common feature of the confusional states,
can be demonstrated by_______
tests of serial subtraction, and
the spelling of words (or repeating a phone number)
It tends to be least pronounced in the morning
and increases as the day wears on, peaking in the
early evening hours _________ when the patient is
fatigued, and environmental cues are not as clear
(“sundowning”)
_______ denotes an inability to sustain a
wakeful state without the application of external stimuli
Drowsiness
As a rule, some degree of_________
are coupled with drowsiness, both improving
with arousal
inattentiveness and mild confusion
________ describes a state in which the patient can
be roused only by vigorous and repeated stimuli and
in which arousal cannot be sustained without repeated
stimulation.
Stupor
In stupor
__________ is common, and there is a
reduction or elimination of the natural shifting of body
positions
Restless or stereotyped motor activity
In stupor
_______ and the breathing
pattern may or may not be altered
Tendon and plantar reflexes,
In psychiatry, the term _________`has been used in a second
sense-to denote an uncommon condition in which the
perception of sensory stimuli is presumably normal but
activity is suspended and motor activity is profoundly
diminished
stupor
The patient who i s incapable o f being aroused b y external
stimuli or inner need, is in a state of _______
coma
In lighter stages, sometimes
referred to by the ambiguous terms ____________
most of the above reflexes can be elicited, and the
plantar reflexes may be either flexor or extensor
semicoma or obtundation,
similarities of sleep and stupor
These include yawning, closure of the eyelids, cessation
of blinking and reduction in swallowing, upward
deviation or divergence or roving movements of the
eyes, loss of muscular tone, decrease or loss of tendon
reflexes, and even the presence of Babinski signs and
irregular respirations, sometimes Cheyne-Stokes in type
One sign of the
vegetative state is a lack of consistent__________ of
objects
visual following
EEG patterns of PVS
low amplitude delta-frequency background activity,
burst suppression, widespread alpha and theta activity,
alpha coma pattern, and sleep spindles
In the initial days and weeks, this syndrome of
unconscious awakening has been referred to as the vegetative state and, if lasting ______after nontraumatic
and _________ after traumatic injury, the syndrome has
been termed the persistent vegetative state
3 months
12 months
The most common pathologic bases of this state are
_________as a result of closed head trauma,
widespread__________ after cardiac arrest, and thalamic necrosis from a number of causes
diffuse cerebral injury
necrosis of the cortex
PVS is a state in which the cortex
is either diffusely injured or effectively disconnected and
isolated from the __________ or the thalamic nuclei are
destroyed.
thalamus,
The vegetative state or the minimally conscious state
described further on, may also be the terminal phase
of progressive cortical degenerative processes such as
_________
Alzheimer and Creutzfeldt-Jakob disease
the profound and widespread
dysfunction of the cerebrum is reflected by
extreme reductions in cerebral blood flow and metabolism,
measured with _________
positron emission tomography
PET
____________ as
necessary for integrated consciousness
posterior parietal regions
preserved autonomic and respiratory function without cognition include \_\_\_\_\_\_\_\_ and \_\_\_\_\_\_\_\_\_\_\_
apallic syndrome
neocortical death
A study by the Multi-Society Task Force on PVS concluded
that the outcome from a vegetative state is better in
________
traumatic as compared to nontraumatic cases
In minimally conscious state,
improve function by stimulating
the ___________ through
implanted electrodes in a patient who had been initially
vegetative and made a natural transition to a minimally
conscious state after traumatic brain injury
medial (interlaminar) thalamic nuclei
there is little or no disturbance of consciousness, but
only an inability of the patient to respond adequately
locked in syndrome
other term for locked in syndrome
deefferented state or pseudocoma
a condition in which the patient is awake but was unresponsive
(actually their patient was able to answer in whispered
monosyllables).
akinetic mutism
This state of apparent vigilance in an imperceptive
and unresponsive patient has been referred to by
French authors as ________
coma vigile
The term akinetic mutism has been applied to yet
another group of patients who are silent and inert as a
result of bilateral lesions usually of the ____________ leaving intact the motor and sensory
pathways; the patient is profoundly apathetic, lacking to
an extreme degree the psychic drive or impulse to action
anterior parts of the frontal lobes,
The patient with ________appears unresponsive, in
a state that simulates stupor, light coma, or akinetic
mutism BUT there is no structural brain abnormality
catatonia
In catatonia, there is also the retention for a long period
of seemingly uncomfortable limb postures _________
(catalepsy).
The central considerations in the diagnosis of brain
death are :
(1) absence of all cerebral functions;
(2) absence of all brainstem functions, including spontaneous respiration; and
(3) irreversibility of the state
in brain death
The absence of brainstem function is judged by
the:
loss of spontaneous eye movements, midposition
of the eyes, and lack of response to oculocephalic and
caloric (oculovestibular) testing; the presence of dilated
or midposition fixed pupils (not smaller than 3 mm);
paralysis of bulbar musculature (no facial movement or
gag, cough, corneal, or sucking reflexes); an absence of
motor and autonomic responses to noxious stimuli; and
absence of respiratory movements
Steps for apnea test
- employing preoxygenation for several minutes
- The patient can then be disconnected
from the respirator for several minutes during
which time 100 percent oxygen is being delivered by
cannula or ventilator that has its pumping mechanism
turned off
Purpose of pre-oxygenation in apnea test
the purpose of which is to displace nitrogen from the alveoli and create a reservoir of oxygen that will diffuse along a gradient into the pulmonary circulation
what happens if you remove the respiratot in apnea test
this allows the arterial Pco2 to rise to 50 to 60
mm Hg (typically, C02 rises approximately 2.5 mm Hg
per minute at normal body temperature-slower if the
patient is hypothermic
The hypercarbia serves both as a ________and a confirmation that spontaneous
ventilation has failed.
stimulus to breathing
effects of the apnea test
hypotension, hypoxemia, cardiac arrhythmias,
and barotrauma
In brain death
this condition leads inability to produce tachycardia in response to the injection of atropine; this reflects the loss of innervation of the heart by the medullary vagal neurons
DI
EEG tracing for confirmation of brain death
isoelectric tracing
__________ is
considered to be present if there is no electrical potential
of more than 2 m V during a 30-min recording except for
artifacts created by the ventilator, electrocardiograph,
and surrounding electrical devices
Electrocerebral silence
Other ddx for reversible isoelectric tracing:
- profound hypothermia
- intoxication with sedative-hypnotic drugs
- and immediately following cardiac arrest
In brain death, testing.
If cardiac arrest was the
antecedent event, or the cause of neurologic damage is
unclear, or drug or alcohol intoxication could reasonably
have played a role in suppressing the brainstem reflexes,
it is advisable to wait about ________ before repeating the
testing and pronouncing the patient dead
24 h
In brain death, testing.
The specificity of
radionuclide scanning is close to ________but there
is a self-referential aspect to this statement as the clinical
diagnosis has been used as a gold standard
100 percent
TCD findings for brain death
brain death shows a to-and-fro,
pendelfluss blood-flow pattern in the basal vessels.
the EEG may transiently show diffuse and variable alpha (8- to 12-Hz) activity, which may be mistaken for the physiologic alpha rhythm.
It is not monorhythrnic like normal alpha activity, and
displays no reactivity to sensory stimuli.
alpha coma
Alpha coma is
usually associated with __________
and has a poor prognosis
pontine or diffuse cortical lesions
In cases of intoxication with sedatives,
exemplified by barbiturates and diazepines,_________initially replaces normal rhythms
fast
(beta) activity
Oxygen consumption of ___________ (approximately
half of normal) is incompatible with an alert state
2 mg/min/100 g
Toxins in coma
in DM, ________are present in high concentration;
in uremia, there is probably an accumulation of dialyzable small molecular toxins, notably_________
acetone bodies (acetoacetic acid, P-hydroxybutyric acid, and acetone)
phenolic derivatives of the aromatic amino acids.
In hepatic coma, elevation of blood
NH3 (ammonia) to______ levels corresponds
roughly to the level of coma
5 to 6 times normal
Lactic acidosis may affect the
brain by lowering arterial blood pH to less than _____ The impairment of consciousness that accompanies pulmonary insufficiency is related mainly to ________
7.0.
hypercapnia
In acute hyponatremia_________ of whatever cause, neuronal dysfunction is probably a result of the intracellular movement of water, leading to _______
(Na <120 mEq/L)
neuronal swelling and loss of potassium chloride from the cells
In other types of seizures, in
which consciousness is interrupted from the very beginning, a _________has been postulated (centrencephalic
seizures of Penfield
diencephalic origin
it
has been recognized that interactions with ligand-gated
ion channels, particularly __________and alterations in neurotransmitter function are a more likely mechanism of anesthesiainduced unconsciousness.
gamma-aminobutyric acid
(GABA)-A receptors
Under the title of ____________ a
rare condition has been described in adult men who
displayed a prolonged state of deep sleepiness lasting
from hours to days intermittently over a period
of many years
idiopathic recurring stupor,
In idiopathic recurring stupor, During the bouts,
a 1 00 fold increase of circulating_______ an
ostensibly naturally occurring diazepine agonist,
endozepine-4,
the cerebral peduncle, is pushed against the opposite
free edge of the tentorium (the resulting creasing of the
lateral edge of the peduncle is called the ______
Kernahan notch
This causes weakness and a Babinski sign ipsilateral to
the hemispheral lesion and later, extensor posturing on that side
Kernahan- Woltman phenomenon
coma; medium-sized fixed pupils that are referable to midbrain damage; bilateral decerebrate postures; loss of vestibuloocular (caloric, oculovestibular) responses all of which are the result of pontine damage; irregular breathing patterns that implicate medullary destruction; and death.
central syndrome with rostro-caudal progression
drowsiness in the early stages is accompanied or
preceded by unilateral pupillary dilatation, most often
on the side of the mass, as a result of compression of the
third nerve
uncal syndrome
Chronic administration
of _______ for hypertension can induce
stupor from cyanide toxicity.
nitroprusside
________is observed in
patients with alcohol or barbiturate intoxication, drowning,
exposure to cold, peripheral circulatory failure,
advanced tuberculous meningitis, and myxedema
Hypothermia
Sl0w breathing points to ________
and occasionally to hypothyroidism,
whereas deep, __________should suggest the presence of pneumonia, diabetic or uremic acidosis,
pulmonary edema, or the less-common occurrence of an
intracranial disease that causes central neurogenic hyperventilation
opiate or barbiturate intoxication
rapid breathing (Kussmaul respiration)
Diseases that elevate intracranial pressure or
damage the brain often cause slow, irregular, or __________
cyclic
Cheyne-Stokes respiration
Cherry-red coloration is typical of _______
carbon
monoxide poisoning
Telangiectases and hyperemia of
the face and conjunctivae are the common stigmata of
______
alcoholism;
_______ imparts a characteristic puffiness
of the face, and hypopituitarism an equally characteristic
_______complexion
myxedema
sallow
Thrombotic thrombocytopenic purpura (TIP), disseminated
intravascular coagulation, and fat embolism may
cause _________
diffuse petechiae or purpura
The spoiled-fruit
odor of _______, the uriniferous odor of uremia, the musky and slightly fecal fetor of _______,
and the burnt almond odor of ________
diabetic ketoacidotic coma
hepatic coma
cyanide poisoning
A loss of
______usually precedes enlargement of the pupil
light reaction
As a transitional phenomenon, the pupil may become
oval or pear-shaped or appear to be off center (corectopia)
because of a _______
differential loss of innervation of a
portion of the pupillary sphincter
The ipsilateral pupillary dilatation from
pinching the side of the neck (the ciliospinal reflex) is usually lost in _______
brainstem lesions
Systemic poisoning with ____ or with drugs
that have atropinic qualities, especially the _______
is characterized by wide dilatation and fixity
of the pupils
atropine
tricyclic antidepressants,
Hippus, or fluctuating pupillary size, is
occasionally characteristic of _______
metabolic encephalopathy
“Wrong-way eyes” a paradoxical conjugate
deviation to the side opposite the lesion may sometimes
occur with _____
thalamic and upper brainstem lesions
_________in
which the eyes move down slowly and return rapidly to
the meridian, is observed with coma caused by anoxia
and drug intoxications;
“Ocular dipping,”
In OCM, The response in coma
of metabolic origin or that caused by bihemispheric structural lesions consists of
conjugate movement of the eyes in
the opposite direction
Elicitation of these ocular reflexes
in a comatose patient provides two pieces of information:
(1) evidence of unimpeded function of the midbrain and
pontine tegmental structures that integrate ocular movements and of the oculomotor nerves, and
(2) loss of the
cortical inhibition that normally holds these movements in
check.
Irrigation of one ear with 10 mL of cold water (or
room-temperature water if the patient is arousable)
causes slow conjugate deviation of the eyes__________ followed in a few seconds by _______
toward the irrigated ear,
compensatory
nystagmus
periods
of waxing and waning hyperpnea alternating with a
shorter period of apnea
Cheyne-Stokes respiration
The more conspicuous
respiratory arrhythmias are associated with lesions b____________ and are therefore
found in the late stages of brainstem compression
or with destructive brainstem lesions
below
the level of the reticular-activating system
Lesions of the lower midbrain-upper pontine tegmentum,
either primary or secondary to transtentorial
herniation, may give rise to _______
central neurogenic hyperventilation
CNH
This disorder is characterized by an
increase in the rate and depth of respiration to an extent
that produces advanced respiratory alkalosis
central neurogenic hyperventilation
CNH
Low pontine lesions, usually caused b y basilar artery
occlusion, sometimes cause __________ (a pause of
2 to 3 s in full inspiration) or so-called short-cycle CheyneStokes respiration, in which a few rapid deep breaths alternate with apneic cycles
apneustic breathing
With lesions of the dorsomedial
part of the medulla, the rhythm of breathing is chaotic,
being irregularly interrupted and each breath varying
in rate and depth ______
(Biot breathing; also called “ataxia of
breathing”).
In regard to all forms of
coma, but particularly after cardiac arrest, if there are no
pupillary, corneal, or oculovestibular responses within
_____________, the chances of regaining independent
function are practically nil
1 day of the onset of coma
Other signs that predict a poor outcome are _________
absence of corneal reflexes, eye-opening responses, atonia of the limbs at
1 and 3 days after the onset of coma, and absence of
the cortical component of the somatosensory-evoked
responses on both sides
