Editing Shock (circulatory) (section)

===Distributive===
{{main|Distributive shock}}
{{SIRS}}
[[Distributive shock]] is low blood pressure due to a [[Vasodilation|dilation of blood vessels]] within the body.<ref name="Tint10" /><ref name=":0">{{Cite book |last=Isaac, Jeff. |title=Wilderness and rescue medicine |date=2013 |publisher=Jones & Bartlett Learning |isbn=9780763789206 |oclc=785442005}}</ref> This can be caused by systemic infection ([[Sepsis|septic shock]]), a severe allergic reaction ([[anaphylaxis]]), or spinal cord injury ([[neurogenic shock]]).{{cn|date=February 2025}} {{main|Septic shock}}
* [[Septic shock]] is the most common cause of distributive shock.<ref name="EMB05" /> It is caused by an overwhelming systemic infection resulting in [[vasodilation]] leading to hypotension. Septic shock can be caused by [[Gram negative]] bacteria such as (among others) ''[[Escherichia coli]]'', [[Proteus (bacterium)|Proteus]] species, ''[[Klebsiella pneumoniae]]'' (which have an [[endotoxin]] on their surface that produces adverse biochemical, immunological and occasionally neurological effects which are harmful to the body), other [[Gram-positive]] cocci, such as [[pneumococci]] and [[streptococci]], and certain fungi as well as Gram-positive [[Microbial toxin|bacterial toxins]]. Septic shock also includes some elements of cardiogenic shock. In 1992, the [[American College of Chest Physicians|ACCP]]/[[Society of Critical Care Medicine|SCCM]] Consensus Conference Committee defined septic shock: " ... sepsis-induced hypotension (systolic blood pressure <&nbsp;90&nbsp;mmHg or a reduction of 40&nbsp;mmHg from baseline) despite adequate fluid resuscitation along with the presence of perfusion abnormalities that may include, but are not limited to: [[lactic acidosis]], oliguria, or an acute alteration in mental status. Patients who are receiving [[Inotrope|inotropic]] or vasopressor agents may have a normalized blood pressure at the time that perfusion abnormalities are identified. The pathophysiology behind septic shock is as follows: 1) Systemic [[leukocyte]] adhesion to endothelial cells<ref name="Robbins" /> 2) Reduced [[Myocardial contractility|contractility of the heart]]<ref name="Robbins" /> 3) Activation of the [[coagulation pathway]]s, resulting in [[disseminated intravascular coagulation]]<ref name="Robbins" /> 4). Increased levels of [[neutrophils]]<ref name="Robbins" />
** The main manifestations of septic shock are due to the massive release of [[histamine]] which causes intense dilation of the blood vessels. People with septic shock will also likely be positive for [[Systemic inflammatory response syndrome|SIRS]] criteria. The most generally accepted treatment for these patients is early recognition of symptoms, and early administration of broad spectrum and organism specific antibiotics.<ref name="survsep">{{Cite web |title=Surviving Sepsis Campaign Responds to ProCESS Trial |url=http://www.survivingsepsis.org/SiteCollectionDocuments/SSC-Responds-Process-Trial.pdf |url-status=dead |archive-url=https://web.archive.org/web/20150924111955/http://www.survivingsepsis.org/SiteCollectionDocuments/SSC-Responds-Process-Trial.pdf |archive-date=2015-09-24 |access-date=2015-03-25 |website=Surviving Sepsis Campaign |publisher=Survivingsepsis.org}}</ref>
** Signs of septic shock include:{{cn|date=February 2025}}
*** [[Heart arrhythmia|Abnormal heart rhythms]], often a [[tachycardia|fast heart rate]]
*** Reduced blood pressure
*** [[Oliguria|Decreased urine output]]
*** [[Altered level of consciousness|Altered mental status]]
* [[Anaphylactic shock]] is caused by a severe [[Anaphylaxis|anaphylactic reaction]] to an [[allergen]], [[antigen]], [[drug]], or foreign protein causing the release of [[histamine]] which causes widespread vasodilation, leading to hypotension and increased [[capillary permeability]]. [[File:Signs and symptoms of anaphylaxis.svg|thumb|Signs of anaphylaxis]]Signs typically occur after exposure to an allergen and may include:
** Skin changes, such as [[hives]], itching, flushing, and swelling.{{cn|date=February 2025}}
** Wheezing and [[shortness of breath]].{{cn|date=February 2025}}
** [[Abdominal pain]], [[diarrhea]], and [[vomiting]].{{cn|date=February 2025}}
** Lightheadedness, [[Altered state of consciousness|confusion]], [[headache]]s, [[loss of consciousness]].{{cn|date=February 2025}}
* High spinal injuries may cause [[neurogenic shock]], which is commonly classified as a subset of distributive shock.<ref name="Trauma07" /> The classic symptoms include [[bradycardia|a slow heart rate]] due to loss of cardiac [[sympathetic nervous system|sympathetic tone]] and warm skin due to dilation of the peripheral blood vessels.<ref name="Trauma07" /> (This term can be confused with [[spinal shock]] which is a recoverable loss of function of the [[spinal cord]] after injury and does not refer to the hemodynamic instability.)

====Endocrine====
Although not officially classified as a subcategory of shock, many [[endocrinological]] disturbances in their severe form can result in shock.{{citation needed|date=September 2022}}
* [[Hypothyroidism]] (can be considered a form of [[cardiogenic shock]]) in people who are critically ill patients reduces [[cardiac output]] and can lead to [[hypotension]] and respiratory insufficiency.
* [[Hyperthyroidism|Thyrotoxicosis]] ([[cardiogenic shock]]) may induce a reversible [[cardiomyopathy]].
* Acute [[adrenal insufficiency]] ([[distributive shock]]) is frequently the result of discontinuing [[corticosteroid]] treatment without tapering the dosage. However, surgery and intercurrent disease in patients on corticosteroid therapy without adjusting the dosage to accommodate for increased requirements may also result in this condition.
* Relative [[adrenal insufficiency]] ([[distributive shock]]) in critically ill patients where present [[cortisol|hormone levels]] are insufficient to meet the higher demands.