In physiology and medicine, hypotension refers to an abnormally low blood pressure. This is best understood as a physiologic state, rather than a disease. It is often associated with shock, though not necessarily indicative of it. Hypotension is not to be confused with hypertension, which is high blood pressure, the opposite of hypotension. Hypotension is a fairly rare problem, hypertension is a much more common problem. Hypotension is usually not a serious problem, although in some cases it can be life threatening. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // I00-I99 - Diseases of the circulatory system (I00-I02) Acute rheumatic fever (I00) Rheumatic fever without mention of heart involvement (I01) Rheumatic fever with heart involvement (I02) Rheumatic chorea (I05-I09) Chronic rheumatic heart diseases (I05) Rheumatic mitral valve diseases (I050) Mitral stenosis (I051) Rheumatic mitral insufficiency (I06) Rheumatic aortic... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Disease Bold textDatabase is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... MedlinePlus (medlineplus. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... This article or section does not cite any references or sources. ... For the chemical substances known as medicines, see medication. ... A sphygmomanometer, a device used for measuring arterial pressure. ... This article is about the medical condition. ... For other forms of hypertension, see Hypertension (disambiguation). ...

Normal physiology

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. This article or section is in need of attention from an expert on the subject. ... In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. ... Nerves (yellow) Nerves redirects here. ... Norepinephrine A hormone (from Greek όρμή - to set in motion) is a chemical messenger from one cell (or group of cells) to another. ... The Sympathetic Nervous System (SNS) is a branch of the autonomic nervous system. ... Autonomic nervous system innervation, showing the sympathetic and parasympathetic (craniosacral) systems, in red and blue, respectively The parasympathetic nervous system is one of three divisions of the autonomic nervous system. ...

Mechanisms and causes

Reduced blood volume, called hypovolemia, is the most common mechanism producing hypotension. This can result from hemorrhage, or blood loss; insufficient fluid intake, as in starvation; or excessive fluid losses from diarrhea or vomiting. Hypovolemia is often induced by excessive use of diuretics. (Other medications can produce hypotension by different mechanisms.) In physiology and medicine, hypovolemia (also hypovolaemia) is a state of decreased blood volume; more specifically, decrease in volume of blood plasma. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A diuretic (colloquially called a water pill) is any drug or herb that elevates the rate of bodily urine excretion (diuresis). ...

Decreased cardiac output despite normal blood volume, due to severe congestive heart failure, large myocardial infarction, or bradycardia, often produces hypotension and can rapidly progress to cardiogenic shock. Arrhythmias often result in hypotension by this mechanism. Beta blockers can cause hypotension both by slowing the heart rate and by decreasing the pumping ability of the heart muscle. Cardiac output is the volume of blood being pumped by the heart, in particular a ventricle in a minute. ... Congestive heart failure (CHF), also called congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood throughout the body. ... Acute myocardial infarction (AMI or MI), more commonly known as a heart attack, is a disease state that occurs when the blood supply to a part of the heart is interrupted. ... Bradycardia, as applied to adult medicine, is defined as a resting heart rate of under 60 beats per minute, though it is seldom symptomatic until the rate drops below 50 beat/min. ... Cardiogenic shock is based upon an inadequate circulation of blood due to primary failure of the ventricles of the heart to function effectively. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ... Beta blockers or beta-adrenergic blocking agents are a class of drugs used to treat a variety of cardiovascular conditions and some other diseases. ...

Excessive vasodilation, or insufficient constriction of the resistance 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 or of dysautonomia, an intrinsic abnormality in autonomic system functioning. Excessive vasodilation can also result from sepsis, acidosis, or medications, such as nitrate preparations, calcium channel blockers, angiotensin II receptor inhibitors or ACE inhibitors. Many anesthetic agents and techniques, including spinal anesthesia and most inhalational agents, produce significant vasodilation. The blood vessels are part of the circulatory system and function to transport blood throughout the body. ... An arteriole is a blood vessel that extends and branchs out from an artery and leads to capillaries. ... Dysautonomia is any disease or malfunction of the autonomic nervous system. ... Sepsis (in Greek Σήψις, putrefaction) is a serious medical condition, resulting from the immune response to a severe infection. ... Acidosis is an increased acidity (i. ... Glyceryl trinitrate (GTN) has been used to treat angina and heart failure since at least 1880. ... Calcium channel blockers are a class of drugs with effects on the muscle of the heart and the muscles of the rest of the body. ... ACE inhibitors, or inhibitors of Angiotensin_Converting Enzyme, are a group of pharmaceuticals that are used primarily in treatment of hypertension and congestive heart failure, in most cases as the drugs of first choice. ... Spinal anaesthesia is a form of local, or more specifically regional, anaesthesia involving injection of a local anaesthetic into the cerebrospinal fluid (CSF), generally through a long fine needle. ... Inhalational anaesthetics are gases or vapours possessing anaesthetic qualities. ...

Syndromes

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 the classes of blood pressure-lowering medications listed above, many psychiatric medications, in particular antidepressants, can have this side effect. Simple blood pressure and heart rate measurements while lying, seated, and standing can confirm the presence of orthostatic hypotension. Orthostatic hypotension (also known as postural hypotension, orthostatic intolerance and, colloquially, as head rush or a dizzy spell) is a sudden fall in blood pressure, typically greater than 20/10 mm Hg, that occurs when a person assumes a standing position, usually after a prolonged period of rest. ... A recent form of antidepressant medication - Prozac Serotonin-norepinephrine reuptake inhibitor, Venlafaxine An antidepressant, in the most common usage, is a psychiatric medication taken to alleviate clinical depression or dysthymia (milder depression). ...

Neurocardiogenic syncope is a form of dysautonomia characterized by an inappropriate drop in blood pressure while in the upright position. Neurocardiogenic syncope is related to vasovagal syncope in that both occur as a result of increased activity of the vagus nerve, the mainstay of the parasympathetic nervous system. Vasovagal syncope (also vasodepressor syncope or neurocardiogenic syncope) is the most common cause of fainting (syncope in medical terminology). ... Vasovagal syncope is the most common cause of syncope, also known as fainting. ... The vagus nerve (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired cranial nerves, and is the only nerve that starts in the brainstem (within the medulla oblongata) and extends, through the jugular foramen, down below the head, to the abdomen. ...

Another, but rarer form, is Postprandial hypotension, which occurs 30–75 minutes after eating substantial meals. When a great deal of blood is diverted to the intestines to facilitate digestion and absorption, the body must increase cardiac output and peripheral vasoconstriction in order to maintain enough blood pressure to perfuse vital organs, such as the brain. It is believed that postprandial hypotension is caused by the autonomic nervous system not compensating appropriately, because of ageing or a specific disorder. Look up Postprandial in Wiktionary, the free dictionary. ... The intestine is the portion of the alimentary canal extending from the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine. ... For the industrial process, see anaerobic digestion. ... Look up absorption in Wiktionary, the free dictionary. ... Cardiac output is the volume of blood being pumped by the heart, in particular a ventricle in a minute. ... The blood vessels are part of the circulatory system and function to transport blood throughout the body. ... This article or section is in need of attention from an expert on the subject. ...

Indicators

For most individuals, a healthy blood pressure lies from 90/50 mmHg to 135/90 mmHg. A small drop in blood pressure, even as little as 20 mmHg, can result in transient hypotension. A sphygmomanometer, a device used for measuring arterial pressure. ... The torr (symbol: Torr) or millimeter of mercury (mmHg) is a non-SI unit of pressure. ...

Evaluating neurocardiogenic syncope is done with a tilt table test. Vasovagal syncope (also vasodepressor syncope or neurocardiogenic syncope) is the most common cause of fainting (syncope in medical terminology). ... A tilt table test is a medical procedure often used to diagnose dysautonomia or syncope. ...

Symptoms

The cardinal symptom of hypotension is lightheadedness or dizziness. If the blood pressure is sufficiently low, fainting and often seizures will occur. Light-headedness is a common and often unpleasant sensation of dizziness and/or feeling that one may be about to faint, which may be transient, recurrent, or occasionally chronic. ... // Pre-syncope is a sensation of feeling faint. ... It has been suggested that Central Ischaemic Response be merged into this article or section. ... This article is about epileptic seizures. ...

Hypotension, depending on one's own body chemistry and genetics, may often cause mild depression, mostly in regard to taking other medications which do not fit one's personal unique needs. Look up depression in Wiktionary, the free dictionary. ...

Low blood pressure is often accompanied by: (Most of these are related to causes rather than effects of hypotension.)

• Chest pain
• Shortness of breath
• Irregular heartbeat
• Fever higher than 101 °F (38.3 °C)
• Headache
• Stiff neck
• Severe upper back pain
• Cough with phlegm
• Prolonged diarrhea or vomiting
• Inability to eat or drink
• Burning with urination
• Foul-smelling urine
• Adverse effect of medications
• Acute, life-threatening allergic reaction
• Dizziness, or light-headedness, particularly when suddenly standing up from sitting down
• Seizures
• Loss of consciousness
• Profound fatigue

In medicine, chest pain is a symptom of a number of conditions and is generally considered a medical emergency, unless the patient is a known angina pectoris sufferer and the symptoms are familiar (appearing at exertion and resolving at rest, known as stable angina). When the chest pain is not... Dyspnea (Latin dyspnoea, Greek dyspnoia from dyspnoos - short of breath) or shortness of breath (SOB) is perceived difficulty breathing or pain on breathing. ... A cardiac arrhythmia, also called cardiac dysrhythmia, is a disturbance in the regular rhythm of the heartbeat. ... This article needs additional references or sources for verification. ... For other uses, see Fahrenheit (disambiguation). ... Celsius is, or relates to, the Celsius temperature scale (previously known as the centigrade scale). ... A headache (cephalalgia in medical terminology) is a condition of pain in the head; sometimes neck or upper back pain may also be interpreted as a headache. ... Upper back pain, also called middle back pain or thoracic pain, is pain that is felt between the bottom of the neck and top of the lumbar spine. ... Phlegm (pronounced ) is sticky fluid secreted by the typhoid membranes of animals. ... Types 5-7 on the Bristol Stool Chart are often associated with diarrhea Diarrhea (in American English) or diarrhoea (in British English) is a condition in which the sufferer has frequent watery, loose bowel movements (from the Greek word διάρροια; literally meaning through-flowing). Acute infectious diarrhea is a common cause... Vomiting (also throwing up or emesis) is the forceful expulsion of the contents of ones stomach through the mouth and sometimes the nose. ... Dysphagia () is a medical term defined as difficulty swallowing. ... In medicine, specifically urology, dysuria refers to any difficulty in urination. ... This article or section is in need of attention from an expert on the subject. ... A medication is a drug or substance taken to reduce symptoms or cure an illness or medical condition. ... Pancreatitus can be caused by an Allergic Reaction to a food. ... // Pre-syncope is a sensation of feeling faint. ... Light-headedness is a common ailment where individuals feel as though their head are weightless. ... This article is about the medical condition. ... Unconsciousness, more appropriately referred to as loss of consciousness or lack of consciousness, is a dramatic alteration of mental state that involves complete or near-complete lack of responsiveness to people and other environmental stimuli. ... The word fatigue is used in everyday living to describe a range of afflictions, varying from a general state of lethargy to a specific work induced burning sensation within muscle. ...

Treatment

The treatment for hypotension depends on its cause. Asymptomatic hypotension in healthy people usually does not require treatment. Severe hypotension needs to be aggressively treated because reduced blood flow to critical organs including the brain, heart and kidneys may cause organ failure and can ultimately lead to death. Treatment options include systemic vasoconstrictors and other drugs. Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... For other uses, see Brain (disambiguation). ... The heart and lungs, from an older edition of Grays Anatomy. ... Kidneys viewed from behind with spine removed The kidneys are bean-shaped excretory organs in vertebrates. ... This article or section does not adequately cite its references or sources. ... Systemic Relating to, or affecting a particular body system; especially the nervous system. ... A vasoconstrictor, also vasopressor or simply pressor, is any substance that acts to cause vasoconstriction (narrowing of the lumena of blood vessels) and usually results in an increase of the blood pressure. ...

References

• hypotension WebMD
• hypotension Medterms