title: Spontaneous pneumothorax; a multicentre retrospective analysis of emergency treatment, complications and outcomes.
abstract: BACKGROUND
  Spontaneous pneumothorax can be managed initially by observation, aspiration or chest drain insertion.
  
  
  OBJECTIVE
  To determine the clinical features of spontaneous pneumothorax in patients presenting to the emergency department (ED), interventions, outcomes and potential risk factors for poor outcomes after treatment.
  
  
  METHODS
  Retrospective chart review from ED of three major referral and two general hospitals in Australia of presentations with primary spontaneous pneumothorax (PSP) or secondary spontaneous pneumothorax (SSP). Main outcomes were prolonged air leak (>5 days) and pneumothorax recurrence within 1 year.
  
  
  RESULTS
  We identified 225 people with PSP and 98 with SSP. There were no clinical tension pneumothoraces with hypotension. Hypoxaemia (haemoglobin oxygen saturation measured by pulse oximetry ≤92%) occurred only in SSP and in older patients (age >50 years) with PSP. Drainage was performed in 150 (67%) PSP and 82 (84%) SSP. Prolonged air leak occurred in 16% (95% confidence interval 10-23%) of PSP and 31% (21-42%) of SSP. Independent risk factors for prolonged drainage were non-asthma SSP and pneumothorax size >50%. Complications were recorded in 11% (7.5-16%) of those having drains inserted. Recurrences occurred in 5/91 (5%, 1.8-12%) of those treated without drainage versus 40/232 (17%, 13-23%) of those treated by drainage, of which half occurred in the first month after drainage.
  
  
  CONCLUSIONS
  Pneumothorax drainage is associated with substantial morbidity including prolonged air leak. As PSP appears to be well tolerated in younger people even with large pneumothoraces, conservative treatment in this subgroup may be a viable option to improve patient outcomes, but this needs to be confirmed in a clinical trial.
authors.affiliation: Centre for Clinical Research in Emergency Medicine, Harry Perkins Institute of Medical Research, Perth, Western Australia, Australia; Department of Emergency Medicine, Royal Perth Hospital, Perth, Western Australia, Australia; Emergency Medicine, University of Western Australia, Perth, Western Australia, Australia.
authors.forename: S G A
authors.initials: SG
authors.lastname: Brown
authors.forename: E L
authors.initials: EL
authors.lastname: Ball
authors.forename: S P J
authors.initials: SP
authors.lastname: Macdonald
authors.forename: C
authors.initials: C
authors.lastname: Wright
authors.forename: D
authors.initials: D
authors.lastname: McD Taylor
mesh_terms: D000328:Adult; D000368:Aged; D015505:Chest Tubes / Q000009:adverse effects / Q000706:statistics & numerical data; D015897:Comorbidity; D004322:Drainage / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital; D005260:Female; D006491:Hemothorax / Q000453:epidemiology; D006769:Hospitals, General; D006801:Humans; D000860:Hypoxia / Q000209:etiology; D007902:Length of Stay / Q000706:statistics & numerical data; D008171:Lung Diseases / Q000150:complications; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D010360:Patient Transfer; D011030:Pneumothorax / Q000150:complications / Q000453:epidemiology / Q000601:surgery*; D001261:Pulmonary Atelectasis / Q000209:etiology; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012422:Rupture, Spontaneous; D016896:Treatment Outcome; D014946:Wound Infection / Q000209:etiology; D055815:Young Adult
keywords: chest tube/adverse effect; pleural disease; pneumothorax/primary spontaneous; pneumothorax/secondary; pneumothorax/therapy; recurrence