Editing Cardiac arrest (section)

===Cardiopulmonary resuscitation===
{{Main|Cardiopulmonary_resuscitation#Compressions_with_rescue_breaths}}
Early [[cardiopulmonary resuscitation]] (CPR) is essential to surviving cardiac arrest with good neurological function.<ref>{{cite web |title=AHA Releases 2015 Heart and Stroke Statistics {{!}} Sudden Cardiac Arrest Foundation |url=https://www.sca-aware.org/sca-news/aha-releases-2015-heart-and-stroke-statistics |website=www.sca-aware.org |access-date=21 September 2019}}</ref><ref name="Walls-2017">{{Cite book|title=Rosen's emergency medicine : concepts and clinical practice| veditors = Walls RM, Hockberger RS, Gausche-Hill M |isbn=9780323390163|oclc=989157341|date = 2017-03-09| vauthors = Walls R, Hockberger R, Gausche-Hill M | publisher = Elsevier Health Sciences }}</ref> It is recommended that it be started as soon as possible with minimal interruptions once begun. The components of CPR that make the greatest difference in survival are [[chest compressions]] and defibrillating shockable rhythms.<ref name="Wang-2017">{{Cite book|title=Tintinalli's emergency medicine manual|veditors = Cydulka RK |isbn= 9780071837026 |oclc=957505642|date = 2017-08-28| vauthors = Wang VJ, Joing SA, Fitch MT, Cline DM, John Ma O, Cydulka RK |publisher = McGraw-Hill Education }}</ref> After defibrillation, chest compressions should be continued for two minutes before another rhythm check.<ref name="Walls-2017" /> This is based on a compression rate of 100-120 compressions per minute, a compression depth of 5–6 centimeters into the chest, full chest recoil, and a ventilation rate of 10 breath ventilations per minute.<ref name="Walls-2017" /> Mechanical chest compressions (as performed by a machine) are no better than chest compressions performed by hand.<ref name="Neumar-2015">{{cite journal |display-authors=6 |vauthors=Neumar RW, Shuster M, Callaway CW, Gent LM, Atkins DL, Bhanji F, Brooks SC, de Caen AR, Donnino MW, Ferrer JM, Kleinman ME, Kronick SL, Lavonas EJ, Link MS, Mancini ME, Morrison LJ, O'Connor RE, Samson RA, Schexnayder SM, Singletary EM, Sinz EH, Travers AH, Wyckoff MH, Hazinski MF |date=November 2015 |title=Part 1: Executive Summary: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care |journal=Circulation |volume=132 |issue=18 Suppl 2 |pages=S315–S367 |doi=10.1161/cir.0000000000000252 |pmid=26472989 |doi-access=free}}</ref> It is unclear if a few minutes of CPR before defibrillation results in different outcomes than immediate defibrillation.<ref>{{cite journal |vauthors=Huang Y, He Q, Yang LJ, Liu GJ, Jones A |date=September 2014 |title=Cardiopulmonary resuscitation (CPR) plus delayed defibrillation versus immediate defibrillation for out-of-hospital cardiac arrest |journal=The Cochrane Database of Systematic Reviews |volume=9 |issue=9 |pages=CD009803 |doi=10.1002/14651858.CD009803.pub2 |pmc=6516832 |pmid=25212112}}</ref>

Correctly performed bystander CPR has been shown to increase survival, however it is performed in fewer than 30% of out-of-hospital cardiac arrests (OHCAs) {{as of|2007|lc=y}}.<ref name="Mutchner-2007" /> A 2019 meta-analysis found that use of dispatcher-assisted CPR improved outcomes, including survival, when compared with undirected bystander CPR.<ref>{{cite journal | vauthors = Nikolaou N, Dainty KN, Couper K, Morley P, Tijssen J, Vaillancourt C | title = A systematic review and meta-analysis of the effect of dispatcher-assisted CPR on outcomes from sudden cardiac arrest in adults and children | journal = Resuscitation | volume = 138 | pages = 82–105 | date = May 2019 | pmid = 30853623 | doi = 10.1016/j.resuscitation.2019.02.035 | s2cid = 73727100 | url = http://wrap.warwick.ac.uk/114478/1/WRAP-systematic-review-meta-analysis-effect-dispatcher-assisted-CPR-Couper-2019.pdf }}</ref> Likewise, a 2022 systematic review on exercise-related cardiac arrests supported early intervention of bystander CPR and AED use (for shockable rhythms) as they improve survival outcomes.<ref>{{cite journal | vauthors = Grubic N, Hill B, Phelan D, Baggish A, Dorian P, Johri AM | title = Bystander interventions and survival after exercise-related sudden cardiac arrest: a systematic review | journal = British Journal of Sports Medicine | volume = 56 | issue = 7 | pages = 410–416 | date = April 2022 | pmid = 34853034 | doi = 10.1136/bjsports-2021-104623 | s2cid = 244800392 }}</ref>

If high-quality CPR has not resulted in return of spontaneous circulation and the person's heart rhythm is in [[asystole]], stopping CPR and pronouncing the person's death is generally reasonable after 20 minutes.<ref name="Resuscitation Council (UK)" /> Exceptions to this include certain cases with [[hypothermia]] or [[drowning]] victims.<ref name="Wang-2017" /><ref name="Resuscitation Council (UK)">{{cite web |author1=Resuscitation Council (UK) |title=Pre-hospital cardiac arrest |url=https://www.resus.org.uk/pages/prehosca.pdf |url-status=dead |archive-url=https://web.archive.org/web/20150513032323/http://www.resus.org.uk/pages/prehosca.pdf |archive-date=13 May 2015 |access-date=3 September 2014 |website=www.resus.org.uk |page=41}}</ref> Some of these cases should have longer and more sustained CPR until they are nearly [[Normothermia|normothermic]].<ref name="Wang-2017" />

If cardiac arrest occurs after 20 weeks of pregnancy, the uterus should be pulled or pushed to the left during CPR.<ref name="Lavonas-2015" /> If a pulse has not returned by four minutes, an emergency [[Cesarean section]] is recommended.<ref name="Lavonas-2015" />