Editing Orthostatic hypotension (section)

{{short description|Drop in blood pressure when standing up or sitting down}}
{{Redirect|Head rush|the television science series|Head Rush (TV series)}}
{{Infobox medical condition (new)
| name = Orthostatic hypotension
| synonyms = Orthostasis ''([[ellipsis (linguistics)|elliptical]] jargon)'', postural hypotension, positional hypotension, neurogenic orthostatic hypotension
| image = 
| caption = 
| field = [[Cardiology]], [[neurology]]
| symptoms = Symptoms that are worse when sitting or standing and improve when lying down, including lightheadedness, vertigo, tinnitus, slurred speech, confusion, coathanger pain in neck and shoulders, grayed or blurred vision, severe fatigue, fainting or near fainting
| complications = Cumulative brain damage, Possiblity of injury or death from falls
| onset = 
| duration = 
| types = 
| causes = 
| risks = 
| diagnosis = In-office (lie down for at least 20 minutes, take BP; stand for 3 minutes, take BP), or tilt-table testing by an autonomic specialist
| differential = 
| prevention = 
| treatment = Identify and treat causes (medications, dehydration), midodrine, compression garments, bed tilting
| medication = 
| prognosis = Depends on frequency, severity, and underlying cause; neurogenic orthostatic hypotension is a chronic, debilitating, and often progressively fatal condition<ref>{{cite journal | vauthors = Arnold AC, Raj SR | title = Orthostatic Hypotension: A Practical Approach to Investigation and Management | journal = The Canadian Journal of Cardiology | volume = 33 | issue = 12 | pages = 1725–1728 | date = December 2017 | pmid = 28807522 | pmc = 5693784 | doi = 10.1016/j.cjca.2017.05.007 }}</ref>
| frequency = 
| deaths = 
}}

'''Orthostatic hypotension''', also known as postural hypotension,<ref>{{DorlandsDict|nine/100012758|Orthostatic hypotension}}</ref> is a medical condition wherein a person's [[blood pressure]] drops when they are standing up ([[orthostasis]]) or sitting down. Primary orthostatic hypotension is also often referred to as neurogenic orthostatic hypotension.<ref>{{cite journal | vauthors = Ricci F, De Caterina R, Fedorowski A | title = Orthostatic Hypotension: Epidemiology, Prognosis, and Treatment | journal = Journal of the American College of Cardiology | volume = 66 | issue = 7 | pages = 848–860 | date = August 2015 | pmid = 26271068 | doi = 10.1016/j.jacc.2015.06.1084 | doi-access = free }}</ref> The drop in blood pressure may be sudden ([[vasovagal]] orthostatic hypotension), within 3 minutes (classic orthostatic hypotension) or gradual (delayed orthostatic hypotension).<ref>{{Cite web|url=https://www.ninds.nih.gov/disorders/all-disorders/orthostatic-hypotension-information-page|title=Orthostatic Hypotension Information Page {{!}} National Institute of Neurological Disorders and Stroke|website=www.ninds.nih.gov|access-date=2017-03-26}}</ref> It is defined as a fall in [[Systole|systolic]] blood pressure of at least 20&nbsp;mmHg or [[diastolic]] blood pressure of at least 10&nbsp;mmHg after 3 minutes of standing. It occurs predominantly by delayed (or absent) [[Vasoconstriction|constriction]] of the lower body [[blood vessel]]s, which is normally required to maintain adequate blood pressure when changing the position to standing. As a result, blood pools in the blood vessels of the legs for a longer period, and less is returned to the heart, thereby leading to a reduced [[cardiac output]] and inadequate blood flow to the brain.

Very mild occasional orthostatic hypotension is common and can occur briefly in anyone, although it is prevalent in particular among the elderly and those with known low blood pressure. Severe drops in blood pressure can lead to [[fainting]], with a possibility of injury. Moderate drops in blood pressure can cause confusion/inattention, [[delirium]], and episodes of [[ataxia]]. Chronic orthostatic hypotension is associated with [[cerebral hypoperfusion]] that may accelerate the pathophysiology of [[dementia]].<ref name=pmid31357238>{{cite journal | vauthors = Hase Y, Polvikoski TM, Firbank MJ, Craggs LJ, Hawthorne E, Platten C, Stevenson W, Deramecourt V, Ballard C, Kenny RA, Perry RH, Ince P, Carare RO, Allan LM, Horsburgh K, Kalaria RN | display-authors = 6 | title = Small vessel disease pathological changes in neurodegenerative and vascular dementias concomitant with autonomic dysfunction | journal = Brain Pathology | volume = 30 | issue = 1 | pages = 191–202 | date = January 2020 | pmid = 31357238 | doi = 10.1111/bpa.12769 | pmc = 8018165 | s2cid = 19310855 }}</ref> Whether it is a causative factor in dementia is unclear.<ref name=pmid24590841>{{cite journal | vauthors = Sambati L, Calandra-Buonaura G, Poda R, Guaraldi P, Cortelli P | title = Orthostatic hypotension and cognitive impairment: a dangerous association? | journal = Neurological Sciences | volume = 35 | issue = 6 | pages = 951–957 | date = June 2014 | pmid = 24590841 | doi = 10.1007/s10072-014-1686-8 | s2cid = 19310855 }}</ref>

The numerous possible causes for orthostatic hypotension include certain medications (e.g. [[alpha blocker]]s), [[autonomic neuropathy]], [[Hypovolemia|decreased blood volume]], [[multiple system atrophy]],  and age-related blood-vessel stiffness.

Apart from addressing the underlying cause, orthostatic hypotension may be treated with a recommendation to increase salt and water intake (to increase the blood volume), wearing [[compression stockings]], and sometimes medication ([[fludrocortisone]], [[midodrine]], or others). Salt loading (dramatic increases in salt intake) must be supervised by a doctor, as this can cause severe neurological problems if done too aggressively.