12. Depressed consciousness and coma Flashcards
Coma defn
state of depressed consciousness in which pt not aware, not awake, no response to vigorous stim
Disruption of what flow of sensory input and ability to process information may lead to depressed consciousness
visual
aud
olfactory
gustatory
visceral
somatosensory
Consciousness two domains
arousal
awareness
Consciousness: arousal defn
fully awake to arousable with verbal/tactile stim, to not rousable
Consciousness: arousal maintained by?
subcortical structures - brainstem nuclei, thalamus, basal forebran, hypothalamus and ascending reticular activating system
Awareness defn
content of consciousness, ranging from self-aware and coherent to confused, inattentive, or perhaps delu- sional.
Awareness brain structures involved
bilateral cerebral cortices
controlling processing and understanding of sensory input
What CN sit in the medullopontin junction level?
CN VIII, 9, 5
What “seemingly minor” things may effect consciousness of elderly?
accidental overdose, drug-drug interactions, and adverse drug reac- tions. Seemingly minor infections such as a urinary tract infection, upper respiratory infection, or viral gastroenteritis with dehydration may cause depressed consciousness or com
Special populations to consider in coma?
OA
immunocompromised
List 10 ddx causes of coma
hypoglycemia/hyperglycemia
adrenal crisis
pituitary apoplexy
sepsis
Wernicke
Hyponatremia
hyperammonemia
hypercalcemia
uremia
hepatic encephalopathy
thyrotoxic crisis
myxedema coma
heat stroke
high altitiude cerebral edema
hypoglycemic agents
opioids
simple asphyxiants
co
histotoxic hypoxia (cyanide/car fire)
methemoglobinemia
sedatives
toxic etoh
inhalants
psych meds
antivonculsants
anticholinergics
clonidine
beta blockers
salicyclates
NMS
serotonin syndrome
ICH
cortical infarct
cerebellar infarct
basilar a occlusion
List 4 main categories to consider in coma
metabolic
structural
drugs/toxins
infection
Name 8 drugs/categories/environment that can cause coma
hypoglycemic agents
opioids
simple asphyxiants
co
histotoxic hypoxia (cyanide/car fire)
methemoglobinemia
sedatives
toxic etoh
inhalants
psych meds
antivonculsants
anticholinergics
clonidine
beta blockers
salicyclates
Name 8 metabolic causes for coma
hypoglycemia/hyperglycemia
adrenal crisis
pituitary apoplexy
sepsis
Wernicke
Hyponatremia
hyperammonemia
hypercalcemia
uremia
hepatic encephalopathy
thyrotoxic crisis
myxedema coma
heat stroke
high altitiude cerebral edema
What sx of basilar a occlusion may occur?
Hemiparesis or quadriparesis, abnormal spontaneous movements, facial weak- ness, dysarthria, dysphagia
–> locked in syndrome: voluntary loss of all except eyes
Sx and signs of NMS
Hyperpyrexia, muscular rigidity, delirium, autonomic instability, elevated CPK
Tx NMS
Cooling, isotonic fluid; benzodiazepines, bromocriptine
Serotonin syndromeL signs and symptoms
Multiple serotonergic agents, hypertension, tachycardia, hyperreflexia, muscular rigid- ity, tremor, nausea, diarrhea, clonus
Serotonin syndrome tx
Isotonic fluid; check CPK; benzodiazepines; cooling, hydration, cyproheptadine
Salicyclate sx and signs
Nausea, vomiting, tinnitus, delirium, hyperpnea, anion gap metabolic acidosis with mixed respiratory alkalosis
Salicyclate tx
Isotonic fluids; urinary alkalinization with sodium bicarbonate; correct hypokale- mia; consider hemodialysis
Signs and sx clonidine od
Bradycardia, hypotension, somnolence
Clonidine tx
isotonic fluid
vasopresors
Beta blocker sx
Bradycardia, hypotension, hypoglycemia, seizure
Beta blocker tx
Isotonic fluid; glucagon IV (5 mg); atro- pine IV (0.5 mg); vasopressors IV; high dose insulin infusion; transcutaneous or transvenous pacing