Editing Cardiac arrest (section)

===Non-cardiac causes===
Non-cardiac causes account for 15 to 25% of cardiac arrests.<ref name="Drory-1991" /><ref name="Kuisma-1997">{{cite journal | vauthors = Kuisma M, Alaspää A | title = Out-of-hospital cardiac arrests of non-cardiac origin. Epidemiology and outcome | journal = European Heart Journal | volume = 18 | issue = 7 | pages = 1122–1128 | date = July 1997 | pmid = 9243146 | doi = 10.1093/oxfordjournals.eurheartj.a015407 | doi-access = free }}</ref> Common non-cardiac causes include [[respiratory arrest]], [[diabetes]], certain [[medication]]s, and [[blunt trauma]] (especially to the chest).<ref name="NIH2022Causes"/><ref>{{cite journal | vauthors = Smith JE, Rickard A, Wise D | title = Traumatic cardiac arrest | journal = Journal of the Royal Society of Medicine | volume = 108 | issue = 1 | pages = 11–16 | date = January 2015 | pmid = 25572990 | pmc = 4291327 | doi = 10.1177/0141076814560837 }}</ref><ref name="Chen_2018">{{cite journal | vauthors = Chen N, Callaway CW, Guyette FX, Rittenberger JC, Doshi AA, Dezfulian C, Elmer J | title = Arrest etiology among patients resuscitated from cardiac arrest | journal = Resuscitation | volume = 130 | pages = 33–40 | date = September 2018 | pmid = 29940296 | doi = 10.1016/j.resuscitation.2018.06.024 | pmc = 6092216 }}</ref>

* Respiratory arrest will be followed by cardiac arrest unless promptly treated.<ref name="Chen_2018" /> Respiratory arrest can be caused by pulmonary embolus, choking, drowning, trauma, drug overdose, and poisoning.<ref name="NIH2022Causes" /> Pulmonary embolus carries a high mortality rate and may be the triggering cause for up to 5% of cardiac arrests, according to a retrospective study from an urban tertiary care emergency department.<ref>{{cite journal | vauthors = Kürkciyan I, Meron G, Sterz F, Janata K, Domanovits H, Holzer M, Berzlanovich A, Bankl HC, Laggner AN | display-authors = 6 | title = Pulmonary embolism as a cause of cardiac arrest: presentation and outcome | journal = Archives of Internal Medicine | volume = 160 | issue = 10 | pages = 1529–1535 | date = May 2000 | pmid = 10826469 | doi = 10.1001/archinte.160.10.1529 }}</ref> 
* Diabetes-related factors contributing to cardiac arrest include silent myocardial ischemia, nervous system dysfunction, and electrolyte disturbances leading to abnormal cardiac repolarization.<ref>{{cite journal | vauthors = Bergner DW, Goldberger JJ | title = Diabetes mellitus and sudden cardiac death: what are the data? | journal = Cardiology Journal | volume = 17 | issue = 2 | pages = 117–129 | date = 2010 | pmid = 20544609 | url = https://journals.viamedica.pl/cardiology_journal/article/view/21390 }}</ref>
* Certain medications can worsen an existing arrhythmia. Some examples include antibiotics like macrolides, diuretics, and heart medications such as anti-arrhythmic medications.<ref name="NIH2022Causes" />

Additional non-cardiac causes include [[Bleeding|hemorrhage]], [[aortic rupture]], [[hypovolemic shock]], [[pulmonary embolism]], poisoning such as from the [[Jellyfish#Toxicity|stings of certain jellyfish]], and [[electrical injury]].<ref name="Walls-2017" /><ref name="Raab-2008">{{cite journal | vauthors = Raab H, Lindner KH, Wenzel V | title = Preventing cardiac arrest during hemorrhagic shock with vasopressin | journal = Critical Care Medicine | volume = 36 | issue = 11 Suppl | pages = S474–S480 | date = November 2008 | pmid = 20449913 | doi = 10.1097/ccm.0b013e31818a8d7e | publisher = Ovid Technologies (Wolters Kluwer Health) }}</ref><ref name="Voelckel-2000">{{cite journal | vauthors = Voelckel WG, Lurie KG, Lindner KH, Zielinski T, McKnite S, Krismer AC, Wenzel V | title = Vasopressin improves survival after cardiac arrest in hypovolemic shock | journal = Anesthesia and Analgesia | volume = 91 | issue = 3 | pages = 627–634 | date = September 2000 | pmid = 10960389 | doi = 10.1097/00000539-200009000-00024 | publisher = Ovid Technologies (Wolters Kluwer Health) }}</ref><ref name="pmid28444167">{{cite journal | vauthors = Waldmann V, Narayanan K, Combes N, Jost D, Jouven X, Marijon E | title = Electrical cardiac injuries: current concepts and management | journal = European Heart Journal | volume = 39 | issue = 16 | pages = 1459–1465 | date = April 2018 | pmid = 28444167 | doi = 10.1093/eurheartj/ehx142 }}</ref>

Circadian patterns are also recognized as triggering factors in cardiac arrest.<ref>{{cite journal | vauthors = Willich SN, Levy D, Rocco MB, Tofler GH, Stone PH, Muller JE | title = Circadian variation in the incidence of sudden cardiac death in the Framingham Heart Study population | journal = The American Journal of Cardiology | volume = 60 | issue = 10 | pages = 801–806 | date = October 1987 | pmid = 3661393 | doi = 10.1016/0002-9149(87)91027-7 }}</ref> Per a 2021 systematic review, throughout the day there are two main peak times in which cardiac arrest occurs. The first is in the morning hours and the second is in the afternoon.<ref>{{cite journal | vauthors = Tran DT, St Pierre Schneider B, McGinnis GR | title = Circadian Rhythms in Sudden Cardiac Arrest: A Review | journal = Nursing Research | volume = 70 | issue = 4 | pages = 298–309 | date = July 2021 | pmid = 33883500 | doi = 10.1097/NNR.0000000000000512 | s2cid = 233349757 }}</ref> Moreover, survival rates following cardiac arrest were lowest when occurring between midnight and 6am.<ref>{{cite journal | vauthors = Tran DT, St Pierre Schneider B, McGinnis GR | title = Circadian Rhythms in Sudden Cardiac Arrest: A Review | language = en-US | journal = Nursing Research | volume = 70 | issue = 4 | pages = 298–309 | date = July–August 2021 | pmid = 33883500 | doi = 10.1097/NNR.0000000000000512 | s2cid = 233349757 }}</ref>

Many of these non-cardiac causes of cardiac arrest are reversible. A common mnemonic used to recall the reversible causes of cardiac arrest is referred to as the [[Hs and Ts]]. The Hs are [[hypovolemia]], [[Hypoxia (medicine)|hypoxia]], hydrogen cation excess ([[acidosis]]), [[hyperkalemia]], [[hypokalemia]], [[hypothermia]], and [[hypoglycemia]]. The Ts are [[toxin]]s, (cardiac) [[Cardiac tamponade|tamponade]], [[Pneumothorax|tension pneumothorax]], thrombosis ([[myocardial infarction]]), [[Thrombosis|thromboembolism]], and trauma.