Dysautonomia and POTSPresented by Dr. Roy Maynard

October 2, 2013

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Objectives

• Understand basics related to the autonomic nervous system

• Describe normal orthostatic response in transitioning from supine to upright position

• Identify symptoms associated with POTS• Name the most common form of

orthostatic intolerance

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POTS

http://thewishfulartist.blogspot.com/2012_08_01_archive.htmlAccessed on 8/5/13

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Definitions

• Dysautonomia:- malfunction of the autonomic nervous system

• POTS:- Postural Orthostatic Tachycardia Syndrome

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Autonomic Nervous System

• Two Components– Sympathetic

• Fight or flight– Parasympathetic

• Rest or digest

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Autonomic Nervous System• Anatomy

– Lower brainstem• Sympathetic T1- L3• Parasympathetic S2-S4, Cranial Nerves 3, 7, 9, 10

• Function– Subconscious level– Visceral functions– Heart rate, respiration, blood pressure– Digestion, micturation, perspiration, salivation,

pupillary dilatation – Dilatation and constriction of blood vessels (arteries

and veins)

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Autonomic Nervous System

http://www.womenhealthsite.com/images/ans-05.jpgAccessed on 8/5/13

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Normal Orthostatic Response• Standing transfers more than 17 ounces of

blood into the abdomen and legs• Initial period of instability (initial orthostatic

hypotension) ensues and blood pressure may decrease by 30% for 10 to 20 seconds after standing

• Reflex tachycardia happens • Blood pressure restored within 30 to 60

seconds

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Normal Orthostatic Response

• Mechanisms to restore hemodynamics– Arterial vasoconstriction– Elastic recoil of venous blood in dependent

veins– Active venoconstriction in splanchnic veins

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Normal Orthostatic Response

http://www.nymc.edu/fhp/centers/syncope/normal.htmAccessed on 8/5/13

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Douglas Bader

http://en.wikipedia.org/wiki/Douglas_BaderAccessed on 8/5/13

http://en.wikipedia.org/wiki/Supermarine_SpitfireAccessed on 8/5/13

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G-Forces and the Fighter Pilot

http://www.gforces.com/military.htmlAccessed on 8/5/13

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Types of Orthostatic Hypotension

• Initial Orthostatic Hypotension• Orthostatic Hypotension

– Nonneurogenic orthostatic hypotension– Neurogenic orthostatic hypotension

• POTS– Neuropathic POTS– Hyperadrenergic POTS

• Vasovagal Syncope (VVS)

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diagnosis

• Tilt table

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Initial Orthostatic Hypotension

PEDIATRIC Journal, Volume 131,Number 5, May 2013 – Page 969

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Types of Orthostatic Hypotension

• Initial Orthostatic Hypotension• Orthostatic Hypotension

– Non-neurogenic orthostatic hypotension– Neurogenic orthostatic hypotension

• POTS– Neuropathic POTS– Hyperadrenergic POTS

• Postural Vasovagal syncope

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Orthostatic Hypotension

• Non-neurogenic orthostatic hypotension– Common in young– Cause – drugs, dehydration, hemorrhage– Mechanism- incomplete autonomic nervous

system compensation for stressors– Treatment- stop medication, prevent

dehydration

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Orthostatic Hypotension

• Neurogenic orthostatic hypotension– Rare in young people, no increase in heart

rate– Associated with diabetes, amyloidosis,

Parkinson’s disease– Cause- autonomic vasoconstrictor failure– Treatment- physical counter-maneuvers,

• Medications- IV saline, corticosteroids, midodrine, droxidopa

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Types of Orthostatic Hypotension

• Initial Orthostatic Hypotension• Orthostatic Hypotension

– Non-neurogenic orthostatic hypotension– Neurogenic orthostatic hypotension

• POTS– Neuropathic POTS– Hyperadrenergic POTS

• Postural Vasovagal syncope

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https://www.facebook.com/pages/Postural-Orthostatic-Tachycardia-Syndrome-POTS/150392785031462Accessed on 8/5/13

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Postural Orthostatic Tachycardia Syndrome

• Definition: chronic day-to-day symptoms of orthostatic intolerance plus excessive increase in heart rate when upright– HR>30 from baseline

or >120 after 10 minutes during tilt test in adults– HR>40 from baseline in children and teens– Blood pressure usually not low

• Cause: alterations in autonomic nervous system

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Postural Orthostatic Tachycardia Syndrome

• Clinical Presentation– Palpitations– Fatigue– Lightheadedness– Exercise intolerance– Nausea– Headache– Syncope/near syncope

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POTS

http://www.nymc.edu/fhp/centers/syncope/normal.htmAccessed on 8/5/13

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Epidemiology• Females > Males 3:1 to 5:1; > 500,000 in 1999• Triggers: Onset often follows flulike illness, self-

limited autoimmune disease, surgery or injury, pregnancy, rapid growth spurt

• May be associated with joint hypermobility syndromes

• Young women may be underweight; need to differentiate from eating disorders

• Hot weather or hot showers worsens symptoms• Cognitive function may be affected

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POTS

http://www.nymc.edu/fhp/centers/syncope/pots.htmAccessed on 8/5/13

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POTS

• Neuropathic POTS– Cause- loss of regional vasoconstrictive ability– Blood pooling in lower extremities– Heart rate increases to compensate for

decreased circulating blood volume now pooling in lower extremities

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Treatment

• Neuropathic POTS- defect is loss of regional vasoconstrictive ability– Physical counter-manuevers– Salt and water loading– Midodrine– Mestinon– Exercise– Rapid water ingestion

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POTS

• Hyperadrenergic POTS– Increased circulating norepinephrine– May have increased orthostatic blood

pressure– Less common than neuropathic form– Symptoms attributed- anxiety, tremor, cold

sweaty extremities

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Treatment• Hyperadrenergic POTS:- Defect adrenergic

potentiation– Physical counter-manuevers– Beta-blockers– Angiotension receptor blocker– Fludrocortisone

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OUTCOME for patients with POTS

• Adolescent-onset: 80% recover by mid 20’s

• Adult-onset: large percentage recover within 2-5 years

• Some patients will suffer from long term disability associated with POTS

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Types of Orthostatic Hypotension

• Initial Orthostatic Hypotension• Orthostatic Hypotension

– Non-neurogenic orthostatic hypotension– Neurogenic orthostatic hypotension

• POTS– Neuropathic POTS– Hyperadrenergic POTS

• Postural Vasovagal syncope

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Postural Vasovagal Syncope

• Most common form of orthostatic intolerance

• Onset age 15, 2/3 are female• 40% of the population has had at least one

episode in their lifetime

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Treatment

• Postural vasovagal syncope- defect ? Loss of regional vasoconstrictive ability, acute reversible baroreflex dysfunction– Physical counter manuevers– Salt and water– Acute water ingestion– Midodrine– Rapid water ingestion

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Summary• Orthostatic Intolerance defined by

symptoms when upright that are relieved by lying down

• Orthostatic hypotension is a form of orthostatic intolerance

• Initial orthostatic hypotension is a common form of orthostatic intolerance in the young

• Postural vasovagal syncope is the most common form of orthostatic intolerance

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Summary

• POTS is a form of chronic orthostatic intolerance results

• (1) from a circulatory system not responding to autonomic inputs properly

• (2) hyperadrenergic state• (3) chronic bed rest

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The End

• Thanks for coming.• Questions?