Lecture 52: ANS Flashcards
Central autonomic network: cortical
Insular, amygdala, anterior cingulate (goal-directed behavior)
Central autonomic network: subcortical
Hypothalamus/pre-optic area, brainstem nuclei
Central autonomic network: brainstem
AFFERENT: nucleus of solitary tract (visceral afferents/medullary reflexes); EFFERENT: ventrolateral medulla (nucleus ambiguus, dorsal motor nucleus of vagus)
Sympathetic chain ganglia runs through what levels?
T1 - L3
Parasympathetic outflow is divided into what two regions?
Cranial (vagus) and sacral (pelvic/distal GI)
Sympathetics of the eye: general description of tract
From midbrain–> exit in upper thoracic –> rise with chain ganglia –> carotid plexus –> lesser ciliary nerve
Parasympathetic control of the eye travel with which CN? Nucleus?
III; Edinger-Westphal
Horner’s syndrome: lesion, symptoms (3), classical lesions (2)
Lesion of sympathetic innervation; mild ptosis, meiosis, anhidrosis; lesion of apex of lung (Pancoast tumror) or dissection of carotid artery
CN III Palsy symptoms (3)
Down and out, ptosis, mydriais
ANS control of blood pressure regulates slow/rapid changes
Rapid (response to changes in position)
Afferent BP signal (receptors, nerves, nucleus)
Baroreceptors and chemoreceptors; CN IX and X; solitary nucleus
Efferent BP signal (para and sympha)
Parasympathetic to heart via vagus and sympathetic to heart/arterioles
What are two symptoms of dysfunction of BP control?
Hypotension and syncope (brief)
Where is body temperature regulated?
Preoptic area and anterior hypothalamus
Sweating is under para/sympa control? What are these nerves called? Special fact about them?
Sympathetic control; sudomotor fibers; terminal NT is ACh
Two disorders of sweating
Hyperhidrosis and hypohidrpsis
Which sweating disorder is related to lesions/neurodegenerative disorders?
Hypohidrosis
Pelvic innervation (level/type of innervation)
F
Overflow incontinence
Atonic bladder: bladder fails to empty
What is the most common cause of overflow incontnence
Outflow obstruction
Neurological causes of overflow incontinence
Most common: small fiber neuropathy (diabetes); cauda equina/conus medullaris; mononeuropathies
Detrusor hyperreflexia
Spastic bladder: bladder contracts when not trying to urinate
Detrusor dyssnergia
Contraction of sphincter is not coordinated with that of the detrusor due to disconnection from pontine center
What is a first-line test for ANS function?
Continuous BP/HR/respiration monitoring
What are the provocative maneuvers to test ANS function?
Tilt table, sinus arrhythmia, valsalva maneuver
Describe tilt table and normal findings
Patients go from lying down –> 70 degrees to test BP; HR and BP does not change upon tilt
Describe sinus arrhythmia
Test HR variability as we breathe in and out
Describe the Valsalva maneuver and normal findings
Monitors BP response to during continued expiration; BP should initially increase (due to force of breathing), decrease (due to decreased venous return because of increased thoracic pressure), then recover (due to vasoconstriction and HR increase), then drop (due to end of exhale), then increase (due to compensatory mechanisms described above), then return to normal
How do we test sweating (name of two tests, descriptions)?
- Thermoregulatory sweat test: cover body in powder that changes color during sweating and place in hot box; 2. Quantitative Sudomotor Axon Reflex: give sweat gland ACh and see if they respond by sweating
Approach to syncope: 3 realms of differential
- Cardiac; 2. Neurodegenerative (central vs peripheral); 3. “Benign” (vasovagal, POTS)
When orthostatic hypotension is caused by a neuro problem, what is this problem? HR/MAP tilt signs?
Neurodegenerative; increase in HR, decrease in MAP
Vasovagal syncope is what? What brings it on and what are the HR/MAP tilt signs?
“Common faint,” brought on by sudden increase in vagal tone, bradycardia and hypotension
Postural orthostatic tachycardia syndrome (POTS) HR/MAP tilt signs. What can this be associated with (3)?
Increase in HR, no change in MAP; post-viral, migraine, fibromyalgia
What Parkinson’s disease has a large ANS component?
Multiple systems atrophy
What do we call the peripheral counterpart of ANS disorder? Name four causes for long-term neuropathy
Autonomic neuropathy; most common: DM, amyloid (uncommon), hereditary, connective tissue disease
Four causes of acute/subacute autonomic neuropathy
Toxic (chemotherapy), G-B, immune-mediated/post-viral, paraneoplastic
Steps of treatment for orthostatic intolerance
- Review meds; 2. Life style factors: salt + water/stockings/head of bed/strength training; 3. Meds (to increase BP): florineft, midodrine, droxidropa
What medication can be helpful for POTS
Pyridostigmine (ACHE inhibitor)
