100 Cases in Clinical Medicine

CASE 99: SHORTNESS OF BREATH

History

A 50-year-old woman has complained of shortness of breath for 3 months. It has steadily
become more severe and is associated with an occasional cough. Otherwise she has been
well. She smokes 15 cigarettes per day and drinks about 14 units of alcohol each week.
Her 20-year-old son has asthma and she has tried his salbutamol inhaler on two or three
occasions but found it to be of no real benefit. She has tested herself on her son’s peak
flow meter at home and she has obtained values of about 100 L/min. On direct question-
ing she says that the shortness of breath tends to be worse on lying down but there are no
other particular precipitating factors or variations through the day. She works as an office
cleaner and has no significant previous medical history.

Examination

Her respiratory rate is 18 per minute. Pulse rate is 72/min and blood pressure 138/84 mmHg.
The heart sounds are normal. There is a generalized wheeze heard all over the chest but no
other abnormalities.

The chest X-ray is normal and respiratory function tests are performed (Figs 99.1 and

99.2). Results are as follows:

Actual Post-bronchodilator Predicted

FEV 1 (L) 1.20 1.20 3.5–4.3

FVC (L) 4.10 4.1 4.6–5.4

FER (FEV 1 /FVC) (%) 29 29 72–80

PEF (L/min) 80 80 440–540

Residual volume (L) 1.8 1.8 1.6–2.8

Total lung capacity (L) 5.9 5.9 5.1–7.0

FEV 1 : forced expiratory volume in 1 s; FVC, forced vital capacity; FER, forced expiratory

ratio; PEF, peak expiratory flow.

INVESTIGATIONS

Time

Expiratory flow

Volume

Figure 99.1Spirometry.