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Asthma exacerbation

Prevalence
Clinical features
Differential Diagnosis
Investigations
Therapy
Prevention
Prognosis
Investigations

Consider a chest X-ray for complicated cases c to exclude pneumothorax. d  

Why?

  • Chest X-rays yield little information in adults with uncomplicated acute asthma. c
  • Hyperinflation increases the possibility of hypercapnia. c

Hyperinflation on chest X-ray increases the chance of hypercapnia

Patient Target Disorder and
Reference Standard		 Diagnostic Test LR+
(95% CI) 		Post-test Probability LR-
(95% CI) 		Post-test Probability
admitted with acute asthma c
(pre-test probability: 27%) 		hypercapnia
(arterial blood gas) 		hyperinflation on CXR 2.1
(1.6 to 2.9) 		44% 0.51
(0.36 to 0.73) 		16%

 

Expiry date: November 2003
Levels of Evidence used in grading these guides

Authors   B   Wong , CM   Ball
Reviewer   B R   O'Driscoll
CAT Writers   B   Wong , CM   Ball