Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure 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, respectively. A systolic blood pressure of less than 90 millimeters of mercury (mm Hg) or diastolic of less than 60 mm Hg is generally considered to be hypotension. Different numbers apply to children. However, in practice, blood pressure is considered too low only if noticeable symptoms are present.
|Image showing patient having blood pressure checked. Systolic blood pressure less than 90mmHg is considered hypotension (low blood pressure)|
|Specialty||Critical care medicine|
Hypotension is the opposite of hypertension, which is high blood pressure. It is best understood as a physiological state rather than a disease. Severely low blood pressure can deprive the brain and other vital organs of oxygen and nutrients, leading to a life-threatening condition called shock.
Hypotension can be caused by low blood volume (hypovolemia), hormonal changes, widening of blood vessels, anemia, heart problems, or endocrine problems. Some medications can also lead to hypotension. There are also syndromes that can cause hypotension in patients including orthostatic hypotension, vasovagal syncope, and other rarer conditions.
For some people who exercise and are in top physical condition, low blood pressure could be normal. A single session of exercise can induce hypotension and water-based exercise can induce a hypotensive response.
Treatment of hypotension may include the use of intravenous fluids or vasopressors. When using vasopressors, trying to achieve a mean arterial pressure (MAP) of greater than 70 mm Hg does not appear to result in better outcomes than trying to achieve a MAP of greater than 65 mm Hg in adults.
Signs and symptomsEdit
Low blood pressure is sometimes associated with certain symptoms, many of which are related to causes rather than effects of hypotension:
- chest pain
- shortness of breath
- irregular heartbeat
- fever higher than 38.3 °C (101 °F)
- stiff neck
- severe upper back pain
- cough with sputum
- Prolonged diarrhea or vomiting
- dyspepsia (indigestion)
- dysuria (painful urination)
- acute, life-threatening allergic reaction
- loss of consciousness
- profound fatigue
- temporary blurring or loss of vision
- Black tarry stools
Reduced blood volume, hypovolemia, is the most common cause of hypotension. This can result from hemorrhage; insufficient fluid intake, as in starvation; or excessive fluid losses from diarrhea or vomiting. Hypovolemia can be induced by excessive use of diuretics. Low blood pressure may also be attributed to heat stroke which can be indicated by absence of perspiration, light headedness and dark colored urine.
Other medications can produce hypotension by different mechanisms. Chronic use of alpha blockers or beta blockers can lead to hypotension. Beta blockers can cause hypotension both by slowing the heart rate and by decreasing the pumping ability of the heart muscle.
Decreased cardiac output despite normal blood volume, due to severe congestive heart failure, large myocardial infarction, heart valve problems, or extremely low heart rate (bradycardia), often produces hypotension and can rapidly progress to cardiogenic shock. Arrhythmias often result in hypotension by this mechanism.
Excessive vasodilation, or insufficient constriction of the blood vessels (mostly arterioles), causes hypotension. This can be due to decreased sympathetic nervous system output or to increased parasympathetic activity occurring as a consequence of injury to the brain or spinal cord. Dysautonomia, an intrinsic abnormality in autonomic system functioning, can also lead to hypotension. Excessive vasodilation can also result from sepsis, acidosis, or medications, such as nitrate preparations, calcium channel blockers, or AT1 receptor antagonists (Angiotensin II acts on AT1 receptors). Many anesthetic agents and techniques, including spinal anesthesia and most inhalational agents, produce significant vasodilation.
Lower blood pressure is a side effect of certain herbal medicines, which can also interact with several medications. An example is the theobromine in Theobroma cacao, which lowers blood pressure through its actions as both a vasodilator and a diuretic, and has been used to treat high blood pressure.
Orthostatic hypotension, also called postural hypotension, is a common form of low blood pressure. It occurs after a change in body position, typically when a person stands up from either a seated or lying position. It is usually transient and represents a delay in the normal compensatory ability of the autonomic nervous system. It is commonly seen in hypovolemia and as a result of various medications. In addition to blood pressure-lowering medications, many psychiatric medications, in particular antidepressants, can have this side effect. Simple blood pressure and heart rate measurements while lying, seated, and standing (with a two-minute delay in between each position change) can confirm the presence of orthostatic hypotension. Taking these measurements is known as orthostatic vitals. Orthostatic hypotension is indicated if there is a drop of 20 mmHg in systolic pressure (and a 10 mmHg drop in diastolic pressure in some facilities) and a 20 beats per minute increase in heart rate.
Vasovagal syncope is a form of dysautonomia characterized by an inappropriate drop in blood pressure while in the upright position. Vasovagal syncope occurs as a result of increased activity of the vagus nerve, the mainstay of the parasympathetic nervous system. Patients will feel sudden, unprovoked lightheadedness, sweating, changes in vision, and finally a loss of consciousness. Consciousness will often return rapidly once patient is lying down and the blood pressure returns to normal.
Another, but rarer form, is postprandial hypotension, a drastic decline in blood pressure that occurs 30 to 75 minutes after eating substantial meals. When a great deal of blood is diverted to the intestines (a kind of "splanchnic blood pooling") to facilitate digestion and absorption, the body must increase cardiac output and peripheral vasoconstriction to maintain enough blood pressure to perfuse vital organs, such as the brain. Postprandial hypotension is believed to be caused by the autonomic nervous system not compensating appropriately, because of aging or a specific disorder.
Blood pressure is continuously regulated by the autonomic nervous system, using an elaborate network of receptors, nerves, and hormones to balance the effects of the sympathetic nervous system, which tends to raise blood pressure, and the parasympathetic nervous system, which lowers it. The vast and rapid compensation abilities of the autonomic nervous system allow normal individuals to maintain an acceptable blood pressure over a wide range of activities and in many disease states. Even small alterations in these networks can lead to hypotension.
The diagnosis of hypotension is made by first obtaining a blood pressure, either non-invasively with a sphygmomanometer or invasively with an arterial catheter (mostly in an intensive care setting). If the systolic blood pressure is <90mmHg or the diastolic blood pressure is <60mmHg, it would be classified as hypotension. Another way to measure low blood pressure is the MAP (Mean Arterial Pressure) using the arterial catheter  or continuous, non-invasive hemodynamic monitoring which measures intra-operative blood pressure beat-by-beat throughout surgery. A MAP <65mmHg is considered hypotension. Intra-operative hypotension <65 mmHg can lead to an increased risk of acute kidney injury, myocardial injury  or post-operative stroke.
Besides the definitive threshold, an abrupt fall in systolic blood pressure around 30 mmHg from one's typical average systolic pressure can also be diagnosed with hypotension.
The treatment for hypotension depends on its cause. Chronic hypotension rarely exists as more than a symptom. Asymptomatic hypotension in healthy people usually does not require treatment. Adding electrolytes to a diet can relieve symptoms of mild hypotension. A morning dose of caffeine can also be effective. In mild cases, where the patient is still responsive, laying the person in dorsal decubitus (lying on the back) position and lifting the legs increases venous return, thus making more blood available to critical organs in the chest and head. The Trendelenburg position, though used historically, is no longer recommended.
Hypotensive shock treatment always follows the first four following steps. Outcomes, in terms of mortality, are directly linked to the speed that hypotension is corrected. Still-debated methods are in parentheses, as are benchmarks for evaluating progress in correcting hypotension. A study on septic shock provided the delineation of these general principles. However, since it focuses on hypotension due to infection, it is not applicable to all forms of severe hypotension.
- Volume resuscitation (usually with crystalloid or blood products)
- Blood pressure support with a vasopressor (all seem equivalent with respect to risk of death, with norepinephrine possibly better than dopamine). 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 a MAP of greater than 65 mm Hg in adults.
- Ensure adequate tissue perfusion (maintain SvO2 >70 with use of blood or dobutamine)
- Address the underlying problem (i.e., antibiotic for infection, stent or CABG (coronary artery bypass graft surgery) for infarction, steroids for adrenal insufficiency, etc...)
Chronic hypotension sometimes requires the use of medications. Some medications that are commonly used include Fludrocortisone, Erythropoietin, and Sympathomimetics such as Midodrine and Noradrenaline and precursor (L-DOPS).
- Fludrocortisone is the first-line therapy (in the absence of heart failure) for patients with chronic hypotension or resistant orthostatic hypotension. It works by increasing the intravascular volume.
- Midodrine is a therapy used for severe orthostatic hypotension, and works by increasing peripheral vascular resistance.
- Noradrenaline and its precursor L-DOPS are used for primary autonomic dysfunction by increasing vascular tone.
- Erythropoietin is given to patients with neurogenic orthostatic hypotension and it works through increasing vascular volume and viscosity.
The definition of hypotension changes in the pediatric population depending on the child's age as seen in the table below.
|Term Neonates||<60 mmHg|
|Children 1 – 10 years||<70 + (age in years x 2) mmHg|
|Children >10 years||<90 mmHg|
The clinical history provided by the caretaker is the most important part in determining the cause of hypotension in pediatric patients. Symptoms for children with hypotension include increased sleepiness, not using the restroom as much (or at all), having difficulty breathing or breathing rapidly, or syncope. The treatment for hypotension in pediatric patients is similar to the treatment in adults by following the four first steps listed above (see Treatment). Children are more likely to undergo intubation during the treatment of hypotension because their oxygen levels drop more rapidly than adults.
Hypotension, from Ancient Greek hypo-, meaning "under" or "less" + English tension, meaning "'strain" or "tightness". This refers to the under-constriction of the blood vessels and arteries which leads to low blood pressure.
- TheFreeDictionary > hypotension. Citing: The American Heritage Science Dictionary Copyright 2005
- Costanzo, Linda S., 1947- (March 15, 2017). Physiology. Preceded by: Costanzo, Linda S., 1947- (Sixth ed.). Philadelphia, PA. ISBN 978-0-323-51189-6. OCLC 965761862.CS1 maint: multiple names: authors list (link)
- "High Blood Pressure Fact Sheet|Data & Statistics|DHDSP|CDC". www.cdc.gov. 2019-01-09. Retrieved 2020-01-15.
- "Diseases and Conditions Index – Hypotension". National Heart Lung and Blood Institute. September 2008. Retrieved September 16, 2008.
- Mayo Clinic staff (May 23, 2009). "Low blood pressure (hypotension) — Definition". MayoClinic.com. Mayo Foundation for Medical Education and Research. Retrieved October 19, 2010.
- 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. doi:10.1542/peds.2017-1904. ISSN 0031-4005. PMID 28827377.
- Mayo Clinic staff (May 23, 2009). "Low blood pressure (hypotension) — Causes". MayoClinic.com. Mayo Foundation for Medical Education and Research. Retrieved October 19, 2010.
- Kalkwarf, Kyle J.; Cotton, Bryan A. (December 2017). "Resuscitation for Hypovolemic Shock". The Surgical Clinics of North America. 97 (6): 1307–1321. doi:10.1016/j.suc.2017.07.011. ISSN 1558-3171. PMID 29132511.
- Bett, Glenna C. L. (1 May 2016). "Hormones and sex differences: changes in cardiac electrophysiology with pregnancy". Clinical Science. 130 (10): 747–759. doi:10.1042/CS20150710. ISSN 1470-8736. PMID 27128800.
- Oparil, Suzanne; Acelajado, Maria Czarina; Bakris, George L.; Berlowitz, Dan R.; Cífková, Renata; Dominiczak, Anna F.; Grassi, Guido; Jordan, Jens; Poulter, Neil R.; Rodgers, Anthony; Whelton, Paul K. (22 March 2018). "Hypertension". Nature Reviews. Disease Primers. 4: 18014. doi:10.1038/nrdp.2018.14. ISSN 2056-676X. PMC 6477925. PMID 29565029.
- Vieth, Julie T.; Lane, David R. (December 2017). "Anemia". Hematology/Oncology Clinics of North America. 31 (6): 1045–1060. doi:10.1016/j.hoc.2017.08.008. ISSN 1558-1977. PMID 29078923.
- Tewelde, Semhar Z.; Liu, Stanley S.; Winters, Michael E. (February 2018). "Cardiogenic Shock". Cardiology Clinics. 36 (1): 53–61. doi:10.1016/j.ccl.2017.08.009. ISSN 1558-2264. PMID 29173681.
- Bornstein, Stefan R.; Allolio, Bruno; Arlt, Wiebke; Barthel, Andreas; Don-Wauchope, Andrew; Hammer, Gary D.; Husebye, Eystein S.; Merke, Deborah P.; Murad, M. Hassan; Stratakis, Constantine A.; Torpy, David J. (February 2016). "Diagnosis and Treatment of Primary Adrenal Insufficiency: An Endocrine Society Clinical Practice Guideline". The Journal of Clinical Endocrinology and Metabolism. 101 (2): 364–389. doi:10.1210/jc.2015-1710. ISSN 1945-7197. PMC 4880116. PMID 26760044.
- Laurent, Stéphane (October 2017). "Antihypertensive drugs". Pharmacological Research. 124: 116–125. doi:10.1016/j.phrs.2017.07.026. ISSN 1096-1186. PMID 28780421.
- 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.
- Jardine, David L.; Wieling, Wouter; Brignole, Michele; Lenders, Jacques W. M.; Sutton, Richard; Stewart, Julian (June 2018). "The pathophysiology of the vasovagal response". Heart Rhythm. 15 (6): 921–929. doi:10.1016/j.hrthm.2017.12.013. ISSN 1556-3871. PMC 5984661. PMID 29246828.
- Merck Manual Home Edition. "Postprandial Hypotension." Last accessed October 26, 2011.
- Konieczka Katarzyna; Rich Robert; et al. (2014). "Flammer syndrome". EPMA Journal. 5 (1): 11. doi:10.1186/1878-5085-5-11. PMC 4113774. PMID 25075228.
- "Low blood pressure (hypotension)". BUPA.co.uk.
- 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.
- 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.
- 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.
- "What Are the Signs and Symptoms of Hypotension?". nhlbi.nih.gov. National Institutes of Health. November 1, 2010. Archived from the original on October 11, 2014. Retrieved February 17, 2014.
- Perner, Anders; Cecconi, Maurizio; Cronhjort, Maria; Darmon, Michael; Jakob, Stephan M.; Pettilä, Ville; van der Horst, Iwan C. C. (June 2018). "Expert statement for the management of hypovolemia in sepsis". Intensive Care Medicine. 44 (6): 791–798. doi:10.1007/s00134-018-5177-x. hdl:10138/303662. ISSN 1432-1238. PMID 29696295.
- Al Mahri, Saeed; Bouchama, Abderrezak (2018). "Heatstroke". Handbook of Clinical Neurology. 157: 531–545. doi:10.1016/B978-0-444-64074-1.00032-X. ISBN 9780444640741. ISSN 0072-9752. PMID 30459024.
- Singer, Mervyn; Deutschman, Clifford S.; Seymour, Christopher Warren; Shankar-Hari, Manu; Annane, Djillali; Bauer, Michael; Bellomo, Rinaldo; Bernard, Gordon R.; Chiche, Jean-Daniel; Coopersmith, Craig M.; Hotchkiss, Richard S. (2016-02-23). "The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3)". JAMA. 315 (8): 801–810. doi:10.1001/jama.2016.0287. ISSN 0098-7484. PMC 4968574. PMID 26903338.
- Dave, Sagar; Cho, Julia J. (2019), "Neurogenic Shock", StatPearls, StatPearls Publishing, PMID 29083597, retrieved 2020-01-21
- Ripollés Melchor, J.; Espinosa, Á; Martínez Hurtado, E.; Casans Francés, R.; Navarro Pérez, R.; Abad Gurumeta, A.; Calvo Vecino, J. M. (September 2015). "Colloids versus crystalloids in the prevention of hypotension induced by spinal anesthesia in elective cesarean section. A systematic review and meta-analysis". Minerva Anestesiologica. 81 (9): 1019–1030. ISSN 1827-1596. PMID 25501602.
- Joel A. DeLisa; Bruce M. Gans; Nicholas E. Walsh, eds. (2005). "19. Complementary and Alternative Medicine". Physical Medicine and Rehabilitation: Principles and Practice. 1. Lippincott Williams & Wilkins. p. 468.
- Tabassum, Nahida; Feroz Ahmad (2011). "Role of natural herbs in the treatment of hypertension". Pharmacognosy Reviews. 5 (9): 30–40. doi:10.4103/0973-7847.79097. PMC 3210006. PMID 22096316.
- Mitchell ES, Slettenaar M, vd Meer N, Transler C, Jans L, Quadt F, Berry M (2011). "Differential contributions of theobromine and caffeine on mood, psychomotor performance and blood pressure". Physiol. Behav. 104 (5): 816–22. doi:10.1016/j.physbeh.2011.07.027. PMID 21839757.
Theobromine ... lowered blood pressure relative to placebo
- William Marias Malisoff (1943). Dictionary of Bio-Chemistry and Related Subjects. Philosophical Library. pp. 311, 530, 573.
- Theobromine Chemistry – Theobromine in Chocolate. Chemistry.about.com (May 12, 2013). Retrieved on 2013-05-30.
- Kelly, Caleb J (2005). "Effects of theobromine should be considered in future studies". American Journal of Clinical Nutrition. 82 (2): 486–7, author reply 487–8. doi:10.1093/ajcn.82.2.486. PMID 16087999.
- Freeman, Roy; Abuzinadah, Ahmad R.; Gibbons, Christopher; Jones, Pearl; Miglis, Mitchell G.; Sinn, Dong In (11 September 2018). "Orthostatic Hypotension: JACC State-of-the-Art Review". Journal of the American College of Cardiology. 72 (11): 1294–1309. doi:10.1016/j.jacc.2018.05.079. ISSN 1558-3597. PMID 30190008.
- Mar, Philip L.; Raj, Satish R. (January 2018). "Orthostatic hypotension for the cardiologist". Current Opinion in Cardiology. 33 (1): 66–72. doi:10.1097/HCO.0000000000000467. ISSN 1531-7080. PMC 5873970. PMID 28984649.
- Carvalho, André F.; Sharma, Manu S.; Brunoni, André R.; Vieta, Eduard; Fava, Giovanni A. (2016). "The Safety, Tolerability and Risks Associated with the Use of Newer Generation Antidepressant Drugs: A Critical Review of the Literature". Psychotherapy and Psychosomatics. 85 (5): 270–288. doi:10.1159/000447034. ISSN 1423-0348. PMID 27508501.
- Low, Phillip A. (October 2015). "Neurogenic orthostatic hypotension: pathophysiology and diagnosis". The American Journal of Managed Care. 21 (13 Suppl): s248–257. ISSN 1936-2692. PMID 26790109.
- Kenny, R. A.; McNicholas, T. (December 2016). "The management of vasovagal syncope". QJM: Monthly Journal of the Association of Physicians. 109 (12): 767–773. doi:10.1093/qjmed/hcw089. ISSN 1460-2393. PMID 27340222.
- Pavelić, Antun; Krbot Skorić, Magdalena; Crnošija, Luka; Habek, Mario (August 2017). "Postprandial hypotension in neurological disorders: systematic review and meta-analysis". Clinical Autonomic Research. 27 (4): 263–271. doi:10.1007/s10286-017-0440-8. ISSN 1619-1560. PMID 28647892.
- Mountjoy, Margo; et al. (2014). "The IOC consensus statement: beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S)". British Journal of Sports Medicine. 48 (7): 491–7. doi:10.1136/bjsports-2014-093502. PMID 24620037.
- Mookherjee, S. Lai, C., Rennke, St. The UCSF Hospitalist Handbook.CS1 maint: multiple names: authors list (link)
- Walsh, M., Devereaux, P. et al. Relationship between Intraoperative Mean Arterial Pressure and Clinical Outcomes a er Noncardiac Surgery. Anaesthesiology. 2013;119:507-515.
- Bijker J., Persoon S., Peelen L., et al. Intraoperative Hypotension and Perioperative Ischemic Stroke a er General Surgery. Anesthesiology. 2012;116(3):658-664.
- Chobanian AV, Bakris GL, Black HR, Cushman WC, Green LA, Izzo JL, Jones DW, Materson BJ, Oparil S, Wright JT, Roccella EJ (December 2003). "Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure". Hypertension. 42 (6): 1206–52. doi:10.1161/01.HYP.0000107251.49515.c2. PMID 14656957.
- Panwar, Rakshit (2018). "Untreated Relative Hypotension Measured as Perfusion Pressure Deficit During Management of Shock and New-Onset Acute Kidney Injury—A Literature Review". Shock (Augusta, Ga.). Ovid Technologies (Wolters Kluwer Health). 49 (5): 497–507. doi:10.1097/shk.0000000000001033. ISSN 1073-2322. PMID 29040214.
- Sharma, Sandeep; Hashmi, Muhammad F.; Bhattacharya, Priyanka T. (2019), "Hypotension", StatPearls, StatPearls Publishing, PMID 29763136, retrieved 2020-01-23
- Chisholm, Peter; Anpalahan, Mahesan (April 2017). "Orthostatic hypotension: pathophysiology, assessment, treatment and the paradox of supine hypertension". Internal Medicine Journal. 47 (4): 370–379. doi:10.1111/imj.13171. ISSN 1445-5994. PMID 27389479.
- Kettaneh, Nicolas (October 30, 2008). "BestBets: Use of the Trendelenburg Position to Improve Hemodynamics During Hypovolemic Shock". Grand Rapids Medical Education & Research/Michigan State University.
- Rivers, E; Nguyen, B; Havstad, S; Ressler, J; Muzzin, A; Knoblich, B; Peterson, E; Tomlanovich, M; Early Goal-Directed Therapy Collaborative, Group (8 November 2001). "Early goal-directed therapy in the treatment of severe sepsis and septic shock". The New England Journal of Medicine. 345 (19): 1368–77. doi:10.1056/nejmoa010307. PMID 11794169.
- Gamper, G; Havel, C; Arrich, J; Losert, H; Pace, NL; Müllner, M; Herkner, H (15 February 2016). "Vasopressors for hypotensive shock". Cochrane Database of Systematic Reviews. 2: CD003709. doi:10.1002/14651858.CD003709.pub4. PMC 6516856. PMID 26878401.
- Bentzer, P; Griesdale, DE; Boyd, J; MacLean, K; Sirounis, D; Ayas, NT (27 September 2016). "Will This Hemodynamically Unstable Patient Respond to a Bolus of Intravenous Fluids?". JAMA. 316 (12): 1298–309. doi:10.1001/jama.2016.12310. PMID 27673307.
- Arnold, Amy C.; Raj, Satish R. (December 2017). "Orthostatic Hypotension: A Practical Approach to Investigation and Management". The Canadian Journal of Cardiology. 33 (12): 1725–1728. doi:10.1016/j.cjca.2017.05.007. ISSN 1916-7075. PMC 5693784. PMID 28807522.
- "Hypotension (PICU chart)". University of Iowa Stead Family Children's Hospital. 2013-06-05. Retrieved 2020-01-23.
- Mendelson, Jenny (May 2018). "Emergency Department Management of Pediatric Shock". Emergency Medicine Clinics of North America. 36 (2): 427–440. doi:10.1016/j.emc.2017.12.010. ISSN 1558-0539. PMID 29622332.
- "Online Etymology Dictionary". etymonline.com. Archived from the original on March 22, 2016. Retrieved 2017-12-10.