Article Text

Pulmonary puzzles
Flow–volume loop: window to a smooth diagnosis?
  1. C Orton1,
  2. S Ward1,
  3. S Jordan2,
  4. A Menzies-Gow1,
  5. J H Hull1
  1. 1Department of Respiratory Medicine, Royal Brompton Hospital, London, UK
  2. 2Department of Cardiothoracic Surgery, Royal Brompton Hospital, London, UK
  1. Correspondence to Dr C Orton, Department of Respiratory Medicine, Royal Brompton Hospital, London SW3 6HP, UK;chrisorton{at}

Statistics from


A 50-year-old woman was referred with a three-year history of cough, difficulty clearing secretions and intermittent wheeze. Examination revealed normal breath sounds and a chest radiograph was normal.

Clinic spirometry revealed a normal volume–time spirogram (figure 1A) with supra-normal indices: FEV1 3.4 L (119% predicted) and FVC 4.1 L (123% predicted).

Figure 1

(A) Volume–time spirograph. (B) Reproducible early expiratory notch (red arrow) on flow–volume loops.

Full lung function testing was arranged and the flow–volume loop was immediately flagged as abnormal; demonstrating a reproducible notch in the early forced expiratory phase of the manoeuvre (figure 1B).


What is causing …

View Full Text

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles

  • Airwaves
    Andrew Bush Ian Pavord