II. Definition: Orthostasis

  1. Measurement
    1. Occurs within 3 minutes of standing
  2. Orthostatic Blood Pressure
    1. Blood Pressure drop on standing of >20 mmHg systolic or 10 mHg diastolic
  3. Orthostatic Heart Rate
    1. Heart Rate increase on standing of 30 beats per minute

III. Efficacy

  1. Orthostatic Vital Signs have low utility and other measures should be used to assess volume status
    1. Swaminathan In Herbert (2013) EM: Rap 13(11): 6-7
  2. Orthostatic Blood Pressure and pulse are poor indicators of Hypovolemia in Hemorrhage and Dehydration
    1. McGee (1999) JAMA 281(11): 1022-9 [PubMed]
    2. Johnson (1995) Acad Emerg Med 2(8):692-7 [PubMed]
  3. Orthostasis is present in as many as 20-50% of those over age 65 years (and typically asymptomatic)
    1. Rutan (1992) Hypertension 19(6 pt 1): 508-19 [PubMed]
    2. Ooi (1997) jAMA 277(16):1299-304 [PubMed]

IV. Physiology

  1. Event: Rising from lying to standing position
    1. 300 to 800 ml of blood pools in legs
  2. Physiologic response
    1. Lower extremity Muscle Contraction compresses veins
    2. Autonomic response
      1. Baroreceptors in aorta and carotids sense BP change
      2. Sympathetic Nervous System response
        1. Increases vascular tone
        2. Increases Heart Rate and cardiac contractility

V. Symptoms

  1. Dizziness or light headedness on standing

VI. Causes

  1. Medications
    1. See Medication Causes of Orthostatic Hypotension
  2. Cardiogenic
    1. Myocardial Infarction
    2. Arrhythmia
    3. Aortic Stenosis
    4. Myocarditis
    5. Pericarditis
    6. Bradycardia
  3. Hypovolemia (Tachycardia present, most common)
    1. Dehydration
    2. Hemorrhage
    3. Anemia
    4. Burn Injury
    5. Adrenal Insufficiency
    6. Diabetes Insipidus
    7. Straining
      1. Heavy lifting
      2. Urinating (Micturition Syncope)
  4. Neurogenic Causes
    1. Diabetic Neuropathy
    2. Spinal cord injury
    3. Guillain-Barre Syndrome
    4. Parkinsonism
    5. Tabes Dorsalis
    6. Amyloidosis
    7. Alcohol Abuse
    8. Vitamin B12 Deficiency (Pernicious Anemia)
    9. Syringomyelia
    10. Post-sympathectomy
    11. Human Immunodeficiency Virus (HIV)
    12. Idiopathic Orthostatic Hypotension
    13. Shy-Drager Syndrome
    14. Carotid Sinus Hypersensitivity
      1. Cardioinhibitory Syncope
      2. Vasodepressor Syncope
  5. Venous pooling
    1. Postprandial Hypotension (occurs within 75 minutes of a meal)
    2. Large leg Varices
    3. Prolonged bed rest
    4. Strenuous Exercise
    5. Fever
    6. Sepsis
    7. Heat exposure
    8. Alcohol
  6. Miscellaneous causes
    1. Aging (may be normal over age 70 years)
    2. Hypokalemia

VII. Labs

  1. Basic chemistry panel (Electrolytes, Renal Function tests, Serum Glucose)
  2. Complete Blood Count
  3. Serum Vitamin B12
  4. Electrocardiogram
  5. Consider morning cortisol level
  6. Consider Holter Monitor

VIII. Imaging

IX. Diagnosis

  1. See Head-Up Tilt Table Test
  2. Orthostatic Blood Pressure and Pulse
    1. Supine Blood Pressure, pulse after 3 minutes
    2. Standing Blood Pressure, pulse after 3 minutes
    3. Abnormal if Blood Pressure drops >20 systolic or 10 diastolic
  3. Response to 15 second Valsalva Maneuver
    1. Normally pressure falls, then rises over baseline
    2. Abnormal if pressure does not overshoot baseline
  4. Pulse variation on deep breathing (sinus Arrhythmia)
    1. Normal response
      1. Tachycardia on inspiration
      2. Bradycardia on expiration
    2. Abnormal if <9 beat/min difference during cycle

X. Evaluation

  1. See Head-Up Tilt Table Test
  2. Consider intravascular volume replacement (IV Fluids)
  3. Consider causes above (including medications)

XI. Complications

  1. Orthostatic Syncope

XII. Management

  1. Avoid medications related to Orthostasis
    1. See Medication Causes of Orthostatic Hypotension
    2. Decrease dose or change medication to one less likey to cause Orthostatic Hypotension
      1. Consider stopping Tricyclic Antidepressants, Antipsychotics
  2. Modify diet
    1. Increase salt
      1. Indicated for 24 hour urinary Sodium <170 mmol Sodium in 24 hours
      2. Supplement up to 1-2 grams extra-per day (avoid in CHF, Edematous States)
    2. Increase water intake (>64 ounces daily)
    3. Avoid Alcohol
    4. Eat smaller, more frequent meals (avoid large carbohydrate rich meals)
  3. Modify activity
    1. Avoid heat exposure or strenuous Exercise
    2. Sleep with head of bed slightly elevated
    3. Rise from bed slowly allowing for equilibration
    4. Avoid standing for long periods of time
    5. Isometric Exercises to work arms, legs and abdominal Muscles (e.g. toe raises, thigh contractions, forward flexion at waist)
    6. While standing, move frequently and stand with crossed legs (consider leaning forward)
    7. Avoid work with arms above Shoulder height
    8. Dorsiflex feet several times before standing
    9. Consider Compression Stockings
  4. Consider medication therapy (esp. for neurologic causes)
    1. Review precautions before using
    2. Fludrocortisone (Florinef)
      1. Increases Sodium and water retention
      2. Precaution: Monitor for Hypokalemia
      3. Start at 0.1 mg daily, titrate weekly by 0.1 mg to maximum of 1mg daily
      4. Target
        1. Improved symptoms
        2. Significant Edema
        3. Weight gain > 3.6 kg
    3. Midodrine (ProAmitine)
      1. Limit to specialist use (FDA recommends removing from market due to lack efficacy)
      2. Risk of supine Hypertension (mediction should be taken before 6 pm)
      3. Increases Blood Pressure for 2-3 hours
      4. Contraindicated in Coronary Artery Disease, Hyperthyroidism, Acute Renal Failure
      5. Start at 2.5 three times daily, titrate weekly by 2.5 mg to maximum dose of 10 mg three times daily
    4. Pyridostigmine (Mestinon)
      1. Start at 30 mg bid to tid and titrate to symptom control or 60 mg three times daily
    5. Erythropoietin has been used if comorbid Anemia
    6. Northera (droxidopa)
      1. Very expensive ($7800/month) compared to other agents listed above (e.g. Fludrocortisone is $35/month)

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Related Studies

Ontology: Hypotension, Orthostatic (C0020651)

Definition (MSHCZE) Pokles tlaku krve objevující se při přechodu do vzpřímené polohy. Může způsobit přechodnou poruchu prokrvení mozku s krátkým bezvědomím (synkopou) nebo pocitem závrati či nejistoty. Příč. nervové poruchy např. diabetická neuropatie, některé léky např. některá antihypertenziva, značná ztráta krve, selhání nadledvin, dlouhodobý pobyt na lůžku aj. Prevencí při těchto stavech je opatrné a postupné vstávání. (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ )
Definition (NCI) Sudden fall of the blood pressure of at least 20/10 mm Hg when a person stands up.
Definition (CSP) fall in blood pressure associated with dizziness, syncope and blurred vision occurring upon standing or when standing motionless in a fixed position.
Definition (MSH) A significant drop in BLOOD PRESSURE after assuming a standing position. Orthostatic hypotension is a finding, and defined as a 20-mm Hg decrease in systolic pressure or a 10-mm Hg decrease in diastolic pressure 3 minutes after the person has risen from supine to standing. Symptoms generally include DIZZINESS, blurred vision, and SYNCOPE.
Concepts Finding (T033)
MSH D007024
ICD9 458.0
ICD10 I95.1
SnomedCT 155488005, 28651003
English Hypotension, Postural, HYPOTENSION ORTHOSTATIC, HYPOTENSION POSTURAL, Orthostatic hypo-tension, Hypotension, Orthostatic, Orthostatic Hypotension, orthostatic hypotension, orthostatic hypotension (physical finding), orthostatic hypotension (diagnosis), orthostatic hypotension was observed, Hypotension orthostatic, Hypotension postural, HYPOTENSION, ORTHOSTATIC, Postural Hypotension, Hypotension, postural, Hypotension, Orthostatic [Disease/Finding], hypotension postural, Hypotension;orthostatic, Hypotension;postural, hypotension orthostatic, Orthostatic hypotension, Postural hypotension, Orthostatic hypotension (disorder), hypotension; orthostatic, hypotension; postural, orthostatic; hypotension, postural; hypotension, Hypotension, orthostatic, postural hypotension
French HYPOTENSION ORTHOSTATIQUE, Hypotension orthostatique, Hypotension posturale
Portuguese HIPOTENSAO ORTOSTATICA, HIPOTENSAO POSTURAL, Hipotensão ortostática, Hipotensão Ortostática, Hipotensão Postural
Spanish HIPOTENSION ORTOSTATICA, HIPOTENSION POSTURAL, Hipotensión postural, hipotensión arterial ortostática (trastorno), hipotensión arterial ortostática, hipotensión arterial postural, Hipotensión ortostática, Hipotensión Ortostática, Hipotensión Postural
Dutch orthostatische hypotensie, houdingsafhankelijke hypotensie, hypotensie houdingsafhankelijk, houdingsafhankelijk; hypotensie, hypotensie; houdingsafhankelijk, hypotensie; orthostatisch, orthostatisch; hypotensie, Orthostatische hypotensie, Hypotensie, orthostatische, Hypotensie, posturale
German lageabhaengige Hypotonie, Hypotonie lageabhaengig, HYPOTONIE LAGEABHAENGIG, HYPOTONIE ORTHOSTATISCH, Orthostatische Hypotonie, Orthostasesyndrom, Hypotonie, orthostatische, Positionshypotonie
Swedish Hypotoni, ortostatisk
Japanese キリツセイテイケツアツ, タイイセイテイケツアツ, 起立性低血圧, 低血圧-起立性, 体位性低血圧, 立ち眩み, 体位性低血圧症, 立ちくらみ, 起立性低血圧症
Finnish Ortostaattinen hypotensio
Czech Posturální hypotenze, Ortostatická hypotenze, Hypotenze ortostatická, hypotenze ortostatická, posturální hypotenze, ortostatická hypotenze
Italian Ipotensione posturale, Ipotensione ortostatica
Korean 기립성 저혈압
Polish Niedociśnienie ortostatyczne, Hipotonia ortostatyczna
Hungarian Orthostatikus hipotenzió, Hypotensio orthostatica, Orthostatikus alacsony vérnyomás, Orthostatikus hypotensio
Norwegian Ortostatisk hypotensjon

Ontology: Orthostasis (C0149746)

Concepts Sign or Symptom (T184)
MSH D004244
Portuguese Ortoestase
Spanish Ortostasis
French Orthostase
German Orthostase
English orthostasis, Orthostasis
Italian Ortostasi
Norwegian Blodtrykksfall i oppreist stillling, Ortostatisme
Czech závratě při napřímení, vzpřímený postoj, ortostatický pokles tlaku
Dutch Orthostasis

Ontology: Syncope due to orthostatic hypotension (C2316624)

Concepts Disease or Syndrome (T047)
SnomedCT 432524006
English Syncope due to orthostatic hypotension (disorder), Syncope due to orthostatic hypotension
Spanish síncope debido a hipotensión ortostática (trastorno), síncope debido a hipotensión ortostática