Hypotension

Hypotension
Depiction of a hypotension (low blood pressure) patient getting her blood pressure checked
Depiction of a hypotension (low blood pressure) patient getting her blood pressure checked
Image showing patient having blood pressure checked. Systolic blood pressure less than 90 mmHg is considered hypotension (low blood pressure)
SpecialtyCritical care medicine, cardiology
SymptomsDizziness, clumsiness, giddiness, headache, lightheadedness, fatigue, nausea, blurred vision, shakiness, breathlessness, increased thirst, irregular heartbeat, chest pain, fever, seizures
ComplicationsFainting, bleeding
Risk factorsOlder patient, Malnourishment
Diagnostic methodPhysical examination, based on symptoms
TreatmentIntravenous fluid

Hypotension, also known as low blood pressure, is a cardiovascular condition characterized by abnormally reduced blood pressure.[1] Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood[2] and is indicated by two numbers, the systolic blood pressure (the top number) and the diastolic blood pressure (the bottom number), which are the maximum and minimum blood pressures within the cardiac cycle, respectively.[3] A systolic blood pressure of less than 90 millimeters of mercury (mmHg) or diastolic of less than 60 mmHg is generally considered to be hypotension.[4][5] Different numbers apply to children.[6] However, in practice, blood pressure is considered too low only if noticeable symptoms are present.[7]

Symptoms may include dizziness, lightheadedness, confusion, feeling tired, weakness, headache, blurred vision, nausea, neck or back pain, an irregular heartbeat or feeling that the heart is skipping beats or fluttering, and fainting.[4] Hypotension is the opposite of hypertension, which is high blood pressure.[2] It is best understood as a physiological state rather than a disease.[2] Severely low blood pressure can deprive the brain and other vital organs of oxygen and nutrients, leading to a life-threatening condition called shock.[3] Shock is classified based on the underlying cause, including hypovolemic shock, cardiogenic shock, distributive shock, and obstructive shock.[8]

Hypotension can be caused by strenuous exercise, excessive heat, low blood volume (hypovolemia),[9] hormonal changes,[10] widening of blood vessels,[11] anemia,[12] vitamin B12 deficiency,[7][13] anaphylaxis,[7] heart problems,[14] or endocrine problems.[15] Some medications can also lead to hypotension.[16] There are also syndromes that can cause hypotension in patients including orthostatic hypotension,[17] vasovagal syncope,[18] and other rarer conditions.[19][20]

For many people, excessively low blood pressure can cause dizziness and fainting or indicate serious heart, endocrine or neurological disorders.[17]

For some people who exercise and are in top physical condition, low blood pressure could be normal.[21][22] A single session of exercise can induce hypotension and water-based exercise can induce a hypotensive response.[23]

Treatment depends on what causes low blood pressure.[4] Treatment of hypotension may include the use of intravenous fluids or vasopressors.[24] When using vasopressors, trying to achieve a mean arterial pressure (MAP) of greater than 70 mmHg does not appear to result in better outcomes than trying to achieve an MAP of greater than 65 mmHg in adults.[25]

  1. ^ TheFreeDictionary > hypotension. Citing: The American Heritage Science Dictionary Copyright 2005
  2. ^ a b c Costanzo, Linda S. (March 15, 2017). Physiology. Preceded by: Costanzo, Linda S. (Sixth ed.). Philadelphia, PA. ISBN 978-0-323-51189-6. OCLC 965761862.{{cite book}}: CS1 maint: location missing publisher (link)
  3. ^ a b "High Blood Pressure Fact Sheet|Data & Statistics|DHDSP|CDC". www.cdc.gov. Centers for Disease Control and Prevention. 2019-01-09. Retrieved 2020-01-15.
  4. ^ a b c "What Is Low Blood Pressure?". National Heart, Lung, and Blood Institute. 2022-03-24. Retrieved 2024-06-15.
  5. ^ Mayo Clinic staff (2024-06-13). "Low blood pressure (hypotension) — Definition". MayoClinic.com. Mayo Foundation for Medical Education and Research. Retrieved 2024-06-15.
  6. ^ Flynn, Joseph T.; Kaelber, David C.; Baker-Smith, Carissa M.; Blowey, Douglas; Carroll, Aaron E.; Daniels, Stephen R.; Ferranti, Sarah D. de; Dionne, Janis M.; Falkner, Bonita; Flinn, Susan K.; Gidding, Samuel S. (2017-09-01). "Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents". Pediatrics. 140 (3) e20171904 (published September 2017). doi:10.1542/peds.2017-1904. ISSN 0031-4005. PMID 28827377.
  7. ^ a b c Mayo Clinic staff (May 23, 2009). "Low blood pressure (hypotension) — Causes". MayoClinic.com. Mayo Foundation for Medical Education and Research. Retrieved October 19, 2010.
  8. ^ Haseer Koya, Hayas; Paul, Manju (2021), "Shock", StatPearls, Treasure Island (FL): StatPearls Publishing, PMID 30285387, retrieved 2021-11-29
  9. ^ Cite error: The named reference :10 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference :15 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference :16 was invoked but never defined (see the help page).
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  13. ^ Cite error: The named reference B799 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference :18 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference :19 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference :1 was invoked but never defined (see the help page).
  17. ^ a b Joseph, Adrien; Wanono, Ruben; Flamant, Martin; Vidal-Petiot, Emmanuelle (April 2017). "Orthostatic hypotension: A review". Nephrologie & Therapeutique. 13 (Suppl 1): S55–S67. doi:10.1016/j.nephro.2017.01.003. ISSN 1872-9177. PMID 28577744.
  18. ^ Cite error: The named reference :4 was invoked but never defined (see the help page).
  19. ^ Cite error: The named reference :20 was invoked but never defined (see the help page).
  20. ^ Cite error: The named reference :21 was invoked but never defined (see the help page).
  21. ^ "Low blood pressure (hypotension)". Bupa. Archived from the original on 2014-02-23.
  22. ^ "Low blood pressure (hypotension)". Bupa. Retrieved 2024-06-15.
  23. ^ Rodriguez, D; Silva, V; Prestes, J; Rica, RL; Serra, AJ; Bocalini, DS; Pontes FL, Jr; Silva, Valter (2011). "Hypotensive response after water-walking and land-walking exercise sessions in healthy trained and untrained women". International Journal of General Medicine. 4: 549–554. doi:10.2147/IJGM.S23094. PMC 3160863. PMID 21887107.
  24. ^ Hunter, Benton R.; Martindale, Jennifer; Abdel-Hafez, Osama; Pang, Peter S. (September 2017). "Approach to Acute Heart Failure in the Emergency Department". Progress in Cardiovascular Diseases. 60 (2): 178–186. doi:10.1016/j.pcad.2017.08.008. hdl:1805/14380. ISSN 1873-1740. PMID 28865801.
  25. ^ Hylands, M; Moller, MH; Asfar, P; Toma, A; Frenette, AJ; Beaudoin, N; Belley-Côté, É; D'Aragon, F; Laake, JH; Siemieniuk, RA; Charbonney, E; Lauzier, F; Kwong, J; Rochwerg, B; Vandvik, PO; Guyatt, G; Lamontagne, F (July 2017). "A systematic review of vasopressor blood pressure targets in critically ill adults with hypotension". Canadian Journal of Anaesthesia. 64 (7): 703–715. doi:10.1007/s12630-017-0877-1. PMID 28497426.