Hypotension Classification and external resources
ICD-10	I95.
ICD-9	458
DiseasesDB	6539
MedlinePlus	007278
MeSH	D007022

In physiology and medicine, hypotension refers to an abnormally low blood pressure. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify Diseases The International Statistical Classification of Diseases and Related Health Problems 10th Revision ( ICD -10) is a coding of diseases and signs symptoms abnormal findings I00-I99 - Diseases of the Circulatory system (I00-I02 Acute rheumatic fever ( Rheumatic fever without mention of Heart The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify Diseases The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. The Diseases Database is a free Website that provides information about the relationships between medical conditions Symptoms, and Medications. MedlinePlus, with the MedlinePlus Medical Encyclopedia, is a website network containing Health information from the world's largest medical Library Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books Physiology (from Greek grc φύσις physis, "nature origin" and grc -λογία -logia) is the study of the mechanical physical Medicine is the art and science of healing It encompasses a range of Health care practices evolved to maintain and restore Human Health by the Blood pressure is also the title of a short story by Damon Runyan in Guys and Dolls and Other Stories 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 the opposite of hypertension, which is high blood pressure. Hypertension, also referred to as high blood pressure, HTN or HPN, is a medical condition in which the Blood pressure is chronically elevated Hypotension can be life-threatening.

Contents 1 Normal physiology 2 Mechanisms and causes 3 Syndromes 4 Indicators 5 Symptoms 6 Treatment 7 References

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. &trade The autonomic nervous system ( ANS) (or visceral nervous system) is the part of the Peripheral nervous system that acts as a Control In a Sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an Organism. A nerve is an enclosed cable-like bundle of peripheral Axons (the long slender projections of Neurons. Hormones (from Greek ὁρμή - "impetus" are chemicals released by cells that affect cells in other parts of the body The Sympathetic Nervous System ( SNS) is a branch of the Autonomic nervous system along with the Enteric nervous system and Parasympathetic nervous The parasympathetic Nervous system ( PSNS) is a division of the Autonomic nervous system (ANS along with the Sympathetic nervous system 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.

Mechanisms and causes

Reduced blood volume, called hypovolemia, is the most common mechanism producing hypotension. In Physiology and Medicine, hypovolemia (also hypovolaemia is a state of decreased Blood volume more specifically decrease in volume of Blood plasma This can result from hemorrhage, or blood loss; insufficient fluid intake, as in starvation; or excessive fluid losses from diarrhea or vomiting. Bleeding, technically known as hemorrhaging / haemorrhaging (see American and British spelling differences) is the loss of Blood from Hypovolemia is often induced by excessive use of diuretics. A diuretic is any Drug that elevates the rate of urination ( Diuresis) (Other medications can produce hypotension by different mechanisms. )

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. Cardiac output (Q is the volume of blood being pumped by the Heart, in particular by a ventricle in a minute Heart failure is a Cardiac condition that occurs when a problem with the structure or function of the Heart impairs its ability to supply Myocardial infarction ( MI or AMI for acute myocardial infarction) also known as a heart attack, occurs when the blood supply 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 Arrhythmias often result in hypotension by this mechanism. Dysrhythmia redirects here For the American band see Dysrhythmia (band. Beta blockers can cause hypotension both by slowing the heart rate and by decreasing the pumping ability of the heart muscle. Beta blockers (sometimes written as β-blocker) are a class of drugs used for various indications but particularly for the management of Cardiac arrhythmias Varieties of meditation and/or other mental-physiological disciplines can create temporary hypotension effects, as well, and should not be considered unusual.

Excessive vasodilation, or insufficient constriction of the resistance blood vessels (mostly arterioles), causes hypotension. An arteriole is a small diameter Blood vessel that extends and branches out from an Artery and leads to capillaries. 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. Dysautonomia is any disease or malfunction of the Autonomic nervous system. Excessive vasodilation can also result from sepsis, acidosis, or medications, such as nitrate preparations, calcium channel blockers, angiotensin II receptor inhibitors or ACE inhibitors. Sepsis is a serious medical condition characterized by a whole-body inflammatory state (called a Systemic inflammatory response syndrome or SIRS caused Acidosis is an increased Acidity (ie an increased Hydrogen ion Concentration) Glyceryl trinitrate (GTN has been used to treat angina and Heart failure since at least 1870 Calcium channel blockers are a class of drugs and natural substances with effects on many excitable cells of the body like the muscle of the Heart, smooth muscles ACE inhibitors, or inhibitors of '''A'''ngiotensin-'''C'''onverting '''E'''nzyme, are a group of Pharmaceuticals that are used primarily in treatment of Hypertension Many anesthetic agents and techniques, including spinal anesthesia and most inhalational agents, produce significant vasodilation. Spinal analgesia, (or commonly called spinal anesthesia or sub-arachnoid block (S Inhalational anaesthetics are gases or Vapours possessing Anaesthetic qualities

Syndromes

Orthostatic hypotension, also called "postural hypotension", is a common form of low blood pressure. Orthostatic hypotension (also known as postural hypotension, and colloquially as head rush or a dizzy spell) is a form of Hypotension in which 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. An antidepressant is a Psychiatric medication used for alleviating major depression or Dysthymia ('milder' depression 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. Orthostatic hypotension is indicated if there is a drop in 20 mmHg of systolic pressure (and a 10 mmHg drop in diastolic pressure in some facilities) and a 20 bpm increase in heart rate.

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. The vagus nerve (ˈveɪˌgəs (VĀ-gəs (also called pneumogastric nerve or cranial nerve X) is the tenth of twelve paired Cranial nerves, and is the

Another, but rarer form, is postprandial hypotension, which occurs 30–75 minutes after eating substantial meals. Postprandial means after eating a meal This term is often used in the context of blood sugar (or blood Glucose) levels which are normally measured 2 hours after eating 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. In Anatomy, the intestine is the segment of the alimentary canal extending from the Stomach to the Anus and in humans and other mammals consists Digestion is the breaking down of chemicals in the body into a form that can be absorbed Cardiac output (Q is the volume of blood being pumped by the Heart, in particular by a ventricle in a minute Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels particularly the large Arteries, Arterioles It is believed that postprandial hypotension is caused by the autonomic nervous system not compensating appropriately, because of ageing or a specific disorder. &trade The autonomic nervous system ( ANS) (or visceral nervous system) is the part of the Peripheral nervous system that acts as a Control

Indicators

For most individuals, a healthy blood pressure ranges from 90/50 mmHg to 130/90 mmHg. Blood pressure is also the title of a short story by Damon Runyan in Guys and Dolls and Other Stories The torr (symbol Torr) is a non- SI unit of Pressure defined as 1/760 of an atmosphere. A small drop in blood pressure, even as little as 20 mmHg, can result in transient hypotension.

Evaluating neurocardiogenic syncope is done with a tilt table test. 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. A symptom' (from Greek σύμπτωμα, "accident misfortune that which befalls" from συμπίπτω, "I befall" from 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 Many different terms are often used to describe what is collectively known as dizziness. If the blood pressure is sufficiently low, fainting and often seizures will occur. An epileptic seizure is caused by excessive and/or hypersynchronous electrical Neuronal activity and is usually self-limiting

Low blood pressure is sometimes associated with: (Most of these are related to causes rather than effects of hypotension. )

Treatment

The treatment for hypotension depends on its cause. The Celsius Temperature scale was 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 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 In Medicine, a cough ( Latin: tussis) is a sudden and often repetitively occurring defence Reflex which helps to clear the large breathing passages Phlegm ( is sticky Fluid secreted by the Mucous membranes of Humans and other Animals. In Medicine, diarrhea, also spelled diarrhoea (see spelling differences) is frequent loose or liquid Bowel movements Acute diarrhea Vomiting (also called throwing up, emesis) is the forceful expulsion of the contents of one's Stomach through the Mouth and sometimes the Dysphagia should not be confused with the similarly pronounced Dysphasia, a language disorder In Medicine, specifically Urology, dysuria refers to painful Urination. Urine is a liquid waste product of the body secreted by the Kidneys by a process of filtration from Blood and Excreted through the Urethra. Medication, also referred to as medicine, can be loosely defined as any substance intended for use in the diagnosis cure mitigation treatment or prevention of disease Allergy is a disorder of the Immune system often also referred to as Atopy. An epileptic seizure is caused by excessive and/or hypersynchronous electrical Neuronal activity and is usually self-limiting See also Unconscious mind. Unconsciousness, more appropriately referred to as loss of Consciousness or lack of consciousness is 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. Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products The brain is the center of the Nervous system in animals All Vertebrates and the majority of Invertebrates have a brain The heart is a muscular organ in all Vertebrates responsible for pumping Blood through the Blood vessels by repeated rhythmic The kidneys are complicated organs that have numerous biological roles Death is the termination of the biological functions that define living Organisms It refers both to a specific Treatment options include systemic vasoconstrictors and other drugs. Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels particularly the large Arteries, Arterioles Adding sodium to a diet can also relieve symptoms of mild hypotension. Sodium (ˈsoʊdiəm is an element which has the symbol Na( Latin natrium, from Arabic natrun) atomic number 11 atomic mass 22

References

• hypotension WebMD
• hypotension Medterms

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