Neurological Emergencies Flashcards
Compare and contrast the meaning of obtunded, stuporous and comatose
Obtunded: Abnormal response to stimuli due to a state of reduced consciousness
Stuporous: unresponsive but still aware of surroundings
Comatose: Of or in a state of deep unconsciousness
Of the 3 mentation changes, which is commonly localized to the forebrain?
Obtunded
What are the causes of mentation changes in small animals?
DAMNITTV:
Degenerative
Anomalous- hydrocephalus can lead to mild mentation changes
Metabolic- hypoglycemia, sodium changes, ketoacidosis etc
Neoplasia- very common
Infectious- bacterial, fungal, protozoal
Immune Mediated- MUE very common
Trauma- very common
Toxin- very common
Vascular- less common than N I or T
What is the first thing you should rule out from your history?
Trauma toxic or metabolic cause
-hypoglycemia if puppy thats not eating
What is the initial clinical approach for patients with mentation changes?
First check the patients temperature, then correct any metabolic derangements, treat for toxin if indicated, check blood pressure, and look for signs of increased intracranial pressure
What is the treatment for a neuro toxin case?
DECONTAMINATE (activated charcoal, induce vomiting), give specific treatment if possible, treat symptoms (muscle relaxer, anti-seizure meds)
- non specific treatments: IV fluids, IV lipids, ion trapping, hemodialysis
-call the pet poison hotline!
If it is determined to be a primary neurologic cause, what is the most important thing you can do for treatment?
Help to maintain cerebral perfusion pressure
What is the equation for CPP and what is the range it should always be between?
MAP-ICP=CPP
Range: 70-120 mmHg
Describe the cushings reflex
Increased ICP leads to reduced cerebral bloodflow. This raises the amount of CO2 in the blood which causes the medullary vasomotor center to send out sympathetic signals to increase MAP. This INCREASES CPP leading to a further increased Intracranial pressure. The increase in MAP also stimulates the carotid baroreceptors and induces vagal stimulation resulting in reflex bradycardia
What are some signs of increased intracranial pressure besides reduced mentation?
Pupil changes (if myotic=hypothalamus, if myiadriatic=brainstem=badd), tetraparesis and ataxia, proprioception defects, cranial nerve deficits, decerebrate posture
Describe the decerebrate posture?
Increased muscle tone in all 4 limbs
What are the fastest ways to decrease intracranial pressure in neuro cases?
Decrease edema with mannitol or 7.2% hypertonic saline
What are the options for long-term management in patients with increased ICP?
Corticosteroids and Diuretics (carbonic anhydrase inhibitor)
If pressure cannot be normalized with medical management, what are the next steps?
Craniectomy and remove the space occupying lesion (tumor, granuloma, or depressed skull fracture)
What are the symptoms of strokes?
Focal non-progressive or convulsive brain signs
How do you confirm that a stroke has occurred?
Imaging of the brain (CT or MRI) and CSF analysis