CAPLAN CH10: Hypo Flashcards
Compared to the usual C-A-B, the sequence changes to ____in patients who drowned.
A-B-C (those with respiratory arrest only usually respond after a few artifical breaths are given).
Features of Balint’s syndrome
- Asimultagnosia
- Optical ataxia
- Apraxia of gaze
Give examples of the following:
A. ischemic-hypoxic brain injury
B. hypoxic brain injury
C. anemic-hypoxic brain injury
D. histotoxic-hypoxic brain injury
A. sudden cardiac arrest
B. drowning or hanging
C. anemia from extreme blood loss
D. cyanide poisoning
The most common initial rhythm in out-of-hospital cardiac arrest is __.
ventricular tachycardia or ventricular fibrillation
With each passing minute of untreated ventricular fibrillation, the likelihood of survival is reduced by __.
7-10%
The most common cause of ventricular tachycardia or ventricular fibrillation cardiac arrest is __.
myocardial ischemia
Level of MAP that secures coronary perfusion?
MAP 65mmHg
The most vulnerable neurons are those in the cerebral cortex especially layers ___.
III, V, VI
Part of thalamus that is mainly activated in consciousness (receiving signals from the midbrain and pons)
intralaminar nuclei
What is the difference between persistent vegetative state and permanent vegetative state?
Persistent- more than 30 days
Permanent- more than 3 months
A condition of severely altered consciousness in which minimal but definite behavioral evidence of self or environmental awareness is demonstrated.
Minimally conscious state
What is the reversal sign?
It is where the CT scan may display the reversal of the gray and white matter densities with relatively increased attenuation of the thalami, brainstem and cerebellum.
The optimal time to image patients after cardiac arrest with MRI is between ___.
Days 3 and 5
T/F. The brainstem is more resistant to hypoxic-ischemic injury than the cerebral cortex.
TRUE. That’s why the absence of brainstem reflexes suggests that the cortex must also be severely damaged.
This is characterized by arrhythmic fine or coarse muscle jerking, markedly exaggerated when the limbs are used and often triggered by startle.
Lance Adams myoclonus
What is the most validated biochemical marker for prognosis after cardiac arrest?
Neuron specifric enolase (NSE)
This level of neuron specific enolase predicts a poor outcome
> 33microgram/L
Even without hypothermia, prognostication after cardiac arrest should be delayed until ___ hours.
72 hours
Where is the internal borderzone?
It is the white matter of the centrum semiovale and corona radiata (this lies in between the deep and superficial perforators of the MCA).
Main mechanism of injury of hanging
Neck compression resulting in jugular venous and carotid arterial obstruction combined with hypoxemia from airway obstruction
The affinity of hemoglobin for carbon monoxide is ___x greater than its affinity for oxygen. Carbon monoxide easily displaces oxygen from hemoglobin.
200x
Reduction of this enzyme to less than 50% can be a cause of defective myelination
Arylsulfatase-A
CT or MRI findings in CO poisoning typically show lesions of the ___.
globus pallidus
putamen
caudate nucleus
thalamus
substantia nigra
Mainstay treatment of CO posioning. Why
100% oxygen
increase the partial pressure of oxygen levels
decrease halflife of CO2
facilitate dissociation from hemoglobin
Sedation of choice for patients with CO poisoning?
non-benzodiazepine sedatives
(such as propofol or dexmedetomidine)
Mechanisms of neurologic manifestations of cardiac failure?
- Decrease cerebral perfusion due to low BP
- HIgh ICP from increased venous hydrostatic pressure
- Associated with pulmonary edema and hydroxemia
- Medication induced
- Autonomic nervous system dysfunction
Proposed causes of abulia in patients with CHF?
Retention of CSFwithin the intracranial cavity outside the brain or in the ventricular system
