Autonomic Disorders And Autonomic Functions Tests Flashcards
What type of response is given when standing erect initiates an orthostatic mechanisms to maintain the mean BP
Postural Response
Postural changes can be stimulated by a
Tilt table
In the lower body negative body pressure , air is evacuated and pressure is reduced in a box enclosing
The lower body below the iliac crest
What are some advantages of the tilt table
Physiological measurements can be made
70 degrees Head-up tilt produces a rapid caudal shift of 500-700ml thoracic venous blood
True or False, the SV increases upon standing
False it decreases
True or false, SV and CO decreases upon standing, according to the tilt table
true
By how much does SV and CO increase according to the tilt able
40%, 15-20%
True or false, Heart rate decreases upon standing
False, it increases
By how much does heart rate increase according to the tilt table
20%
By how much does the total physiological response increase
40%
The Valsalva Manœvre was originally used to inflate the middle ear via
Estachian tubes
What is the function of the Valsalva Manœvre
Assess ANS Responsiveness to circulatory changes
What is the Valsava Manœvre method
Subject closes mouth and nose, then expires forcibly against a 40mmHg resistance for 15 seconds
In the Valsava Manœvre, Pressure inside which 2 passages increases
Pharynx and lungs
In the Valsava Manœvre, the increase in the two passages, results in a sudden increase in which 3 pressures
Intrathoracic, Intra-abdominal and CSF
In the Valsava Manœvre, What valves shut preventing blood flow to the vena cava
Peripheral Venous Valves
In the Valsava Manœvre,, Blood accumulates in which veins
Peripheral veins
In the Valsava Manœvre,, the Aortic flow falls to ________ of normal
50%
What occurs in Phase 1 of Valsava Manœvre
Heart Rate Decreases, Due to an increase in arterial pressure because the intrathoracic pressure adds to the aortic pressure
What occurs in Phase 2 of Valsava Manœvre,
Reflex Tachycardia + TPR increases
Compression of the veins prevents venous return, cardiac filling decreases and MAP falls
What occurs in Phase 3 of Valsava Manœvre,
Heart Rate Increases
Glottis opens, Blood Pressure falls due to sudden fall in intrathoracic pressure
What occurs in Phase 4 of Valsava Manœvre,
Rapid Bradycardia
Blood Presure rebounds due to rapid venous return
Abnomal Valsalva Responses, usually occurs in persons with what disease
Idiopathic Orthostatic Hypotension
Abnomal Valsalva causes ______ in Phases 2 and ______ in phase 4
Fall in BP
Abscence of overshoot and Bradycardia in Phase 4
What type of wave is present in persons with Hypertensive Heart Failure
Square Wave
Very little change in Heart Rate
In high temperatures, animals lose heat by:
Sweating
Vasodilation
In low temperature, animals try to conserve heat by
Vasoconstriction
Piloerection (Horripilation)
Shivering
What test is used to measure ANS testing
Cold Pressor Test
Describe the method of the Cold Pressor Test
Place one limb in cold water and meaure the blood flow in the other limb
How is blood flow measured in the cold pressor test
Venous Occlusion Plethysmography
What hormones are released from the sympathetic nervous system as a result of cool temperatures
NE, E
What part of the hypothalamus detects heat productions and regulate heat loss
Anterior
What disease mainly affects women, which causes increased hypersensitivity to small decreases in temperature
Raynauds disease
What part of the body is Raynauds disease mainly seen
fingers
What is a symptom of Raynaud’s disease
Ischemia and severe pain
True or false, Ischemic pain persists for several minutes
true
What causes an increase in pain for patients with Raynauds disease
Sudden massive increase in blood flow due to vasodilation which causes severe reddening
How is Raynauds disease treated
Cut the sympathetic chain T2-T3 -Fingers
Lumbar Sympathectomy at L2’ L3 - Lower limbs
Stellate ganglion block- cerebral circulation
What is commonly used to treat excessive sweating
Sympathectomy
Why are Ganglionic blockades preferred
To prevent Denervation Supersensitivity
