Editing Pneumothorax (section)

{{Short description|Abnormal collection of air in the pleural space}}
{{Redirect|Collapsed lung}}
{{Good article}}
{{Use dmy dates|date=August 2018}}
{{Infobox medical condition (new)
| name            = Pneumothorax
| synonyms        = Collapsed lung<ref name=Or2004/>
| image           = Blausen 0742 Pneumothorax.png
| caption         = Illustration depicting a collapsed lung or pneumothorax
| alt             = 
| field           = [[Pulmonology]], [[thoracic surgery]]
| pronounce       = 
| symptoms        = Chest pain, [[shortness of breath]], [[fatigue (medicine)|tiredness]]<ref name=NIH2011Sym/>
| onset           = Sudden<ref name=BMJ2014/>
| duration        = 
| causes          = Unknown, trauma<ref name=BMJ2014/>
| risks           = [[COPD]], [[tuberculosis]], [[smog]], smoking<ref name=NIH2011Cau/>
| diagnosis       = [[Chest X-ray]], [[ultrasound]], [[CT scan]]<ref name=Chen2015/>
| differential    = [[Pneumatosis#Bullous emphysema|Lung bullae]],<ref name=BMJ2014/> [[hemothorax]]<ref name=NIH2011Sym/>
| prevention      = [[Smoking cessation]]<ref name=BMJ2014/>
| treatment       = [[Conservative treatment|conservative]], needle aspiration, [[chest tube]], [[pleurodesis]]<ref name=BMJ2014/>
| medication      = 
| frequency       = 20 per 100,000 per year<ref name=BMJ2014/><ref name=Chen2015/>
}}

<!-- Definition and symptoms -->
A '''pneumothorax''' is collection of air in the [[pleural space]] between the [[lung]] and the [[chest wall]].<ref name=BMJ2014/> Symptoms typically include sudden onset of sharp, one-sided [[chest pain]] and [[dyspnea|shortness of breath]].<ref name=NIH2011Sym>{{cite web|title=What Are the Signs and Symptoms of Pleurisy and Other Pleural Disorders|url=http://www.nhlbi.nih.gov/health/health-topics/topics/pleurisy/signs|website=www.nhlbi.nih.gov|access-date=31 October 2016|date=21 September 2011|url-status=live|archive-url=https://web.archive.org/web/20161008061144/https://www.nhlbi.nih.gov/health/health-topics/topics/pleurisy/signs|archive-date=8 October 2016}}</ref> In a minority of cases, a one-way valve is formed by an area of damaged [[Tissue (biology)|tissue]], and the amount of air in the space between chest wall and lungs increases; this is called a tension pneumothorax.<ref name=BMJ2014/> This can cause a steadily worsening [[Hypoxia (medical)|oxygen shortage]] and [[hypotension|low blood pressure]]. This leads to a type of shock called [[obstructive shock]], which can be fatal unless reversed.<ref name=BMJ2014/> Very rarely, both lungs may be affected by a pneumothorax.<ref>{{cite journal | vauthors = Morjaria JB, Lakshminarayana UB, Liu-Shiu-Cheong P, Kastelik JA | title = Pneumothorax: a tale of pain or spontaneity | journal = Therapeutic Advances in Chronic Disease | volume = 5 | issue = 6 | pages = 269–273 | date = November 2014 | pmid = 25364493 | pmc = 4205574 | doi = 10.1177/2040622314551549 }}</ref> It is often called a "'''collapsed lung'''", although that term may also refer to [[atelectasis]].<ref name=Or2004>{{cite book| vauthors = Orenstein DM |title=Cystic Fibrosis: A Guide for Patient and Family|date=2004|publisher=Lippincott Williams & Wilkins|isbn=9780781741521|page=62|url=https://books.google.com/books?id=BGefk9zBqlgC&pg=PA62|language=en|url-status=live|archive-url=https://web.archive.org/web/20161031212134/https://books.google.ca/books?id=BGefk9zBqlgC&pg=PA62|archive-date=31 October 2016}}</ref>

<!-- Cause and risk factors -->
A primary spontaneous pneumothorax is one that occurs without an apparent cause and in the absence of significant [[lung disease]].<ref name=BMJ2014/> A secondary spontaneous pneumothorax occurs in the presence of existing lung disease.<ref name="BMJ2014">{{cite journal | vauthors = Bintcliffe O, Maskell N | title = Spontaneous pneumothorax | journal = BMJ | volume = 348 | pages = g2928 | date = May 2014 | issue = may08 1 | pmid = 24812003 | doi = 10.1136/bmj.g2928 | s2cid = 32575512 }}</ref><ref name="Weinberger">{{cite book | vauthors = Weinberger S, Cockrill B, Mandel J |title=Principles of Pulmonary Medicine |date=2019 |publisher=Elsevier |isbn=9780323523714 |pages=215–216 |edition=7th}}</ref> Smoking increases the risk of primary spontaneous pneumothorax, while the main underlying causes for secondary pneumothorax are [[COPD]], [[asthma]], and [[tuberculosis]].<ref name=BMJ2014/><ref name=NIH2011Cau>{{cite web|title=What Causes Pleurisy and Other Pleural Disorders?|url=http://www.nhlbi.nih.gov/health/health-topics/topics/pleurisy/causes|website=NHLBI|access-date=31 October 2016|date=21 September 2011|url-status=live|archive-url=https://web.archive.org/web/20161008061131/https://www.nhlbi.nih.gov/health/health-topics/topics/pleurisy/causes|archive-date=8 October 2016}}</ref> A traumatic pneumothorax can develop from [[physical trauma]] to the [[chest]] (including a [[blast injury]]) or from a [[iatrogenesis|complication of a healthcare intervention]].<ref>{{cite journal | vauthors = Slade M | title = Management of pneumothorax and prolonged air leak | journal = Seminars in Respiratory and Critical Care Medicine | volume = 35 | issue = 6 | pages = 706–714 | date = December 2014 | pmid = 25463161 | doi = 10.1055/s-0034-1395502 | s2cid = 35518356 }}</ref><ref name="Wolf2009">{{cite journal | vauthors = Wolf SJ, Bebarta VS, Bonnett CJ, Pons PT, Cantrill SV | title = Blast injuries | journal = Lancet | volume = 374 | issue = 9687 | pages = 405–415 | date = August 2009 | pmid = 19631372 | doi = 10.1016/S0140-6736(09)60257-9 | s2cid = 13746434 }}</ref>

<!-- Diagnosis -->
Diagnosis of a pneumothorax by [[physical examination]] alone can be difficult (particularly in smaller pneumothoraces).<ref>{{cite journal | vauthors = Yarmus L, Feller-Kopman D | title = Pneumothorax in the critically ill patient | journal = Chest | volume = 141 | issue = 4 | pages = 1098–1105 | date = April 2012 | pmid = 22474153 | doi = 10.1378/chest.11-1691 | s2cid = 207386345 }}</ref> A [[chest radiograph|chest X-ray]], [[X-ray computed tomography|computed tomography]] (CT) scan, or [[ultrasound]] is usually used to confirm its presence.<ref name="Chen2015">{{cite journal | vauthors = Chen L, Zhang Z | title = Bedside ultrasonography for diagnosis of pneumothorax | journal = Quantitative Imaging in Medicine and Surgery | volume = 5 | issue = 4 | pages = 618–623 | date = August 2015 | pmid = 26435925 | pmc = 4559988 | doi = 10.3978/j.issn.2223-4292.2015.05.04 }}</ref> Other conditions that can result in similar symptoms include a [[hemothorax]] (buildup of [[blood]] in the pleural space), [[pulmonary embolism]], and [[myocardial infarction|heart attack]].<ref name=NIH2011Sym/><ref>{{cite book| vauthors = Peters JR, Egan D, Mick NW | veditors = Nadel ES |title=Blueprints Emergency Medicine|date=2006|publisher=Lippincott Williams & Wilkins|isbn=9781405104616|page=44|url=https://books.google.com/books?id=NvqaWHi1OTsC&pg=PA44|language=en|url-status=live|archive-url=https://web.archive.org/web/20161101041122/https://books.google.ca/books?id=NvqaWHi1OTsC&pg=PA44|archive-date=1 November 2016}}</ref> A large [[Chronic obstructive pulmonary disease#Pathophysiology|bulla]] may look similar on a chest X-ray.<ref name=BMJ2014/>

<!-- Treatment and epidemiology -->
A small spontaneous pneumothorax will typically resolve without treatment and requires only monitoring.<ref name=BMJ2014/> This approach may be most appropriate in people who have no underlying lung disease.<ref name=BMJ2014/> In a larger pneumothorax, or if there is shortness of breath, the air may be removed with a [[syringe]] or a [[chest tube]] connected to a one-way valve system.<ref name=BMJ2014/> Occasionally, [[surgery]] may be required if tube drainage is unsuccessful, or as a preventive measure, if there have been repeated episodes.<ref name=BMJ2014/> The surgical treatments usually involve [[pleurodesis]] (in which the layers of [[pleura]] are induced to stick together) or [[pleurectomy]] (the surgical removal of pleural membranes).<ref name=BMJ2014/> About 17–23 cases of pneumothorax occur per 100,000 people per year.<ref name=BMJ2014/><ref name=Chen2015/> They are more common in men than women.<ref name=BMJ2014/>