Respiratory clinic - a woman with breathlessness and palpitations
Dr Jonathan Bennett, consultant respiratory physician, guides you through a case of a woman who presented to her GP with breathlessness.
A 45-year-old woman presents to her GP with a 12-month history of breathlessness, tight chest and palpitations on exertion. She had previously seen a colleague who had given her a trial of salbutamol with no effect. She had been referred her to the cardiology clinic where she had had a normal exercise test and a diagnosis of non-cardiac breathlessness.
A detailed history reveals that she has episodic breathlessness associated with chest tightness, a sensation of her heart thumping and light headedness. These sensations may come on even at rest and can last from two to three minutes up to 20 to 30 minutes. Further questioning reveals that she often feels breathless when talking - especially on the telephone, she has the sensation of not being able to get ‘quality air in’, often feels the need to take deep or stretching breaths to help, and may occasionally get a sensation of lightheadedness as though she is about to pass out. She has no nocturnal symptoms.
In surgery she is noted to have dysphonia, breath stacking (where sequential partial or full tidal volume inspiratory breaths are taken on top of one another), an upper chest ventilatory pattern and occasional sighing breaths. Cardio-respiratory examination is otherwise unremarkable. Spirometry in surgery is normal. The GP suspects dysfunctional breathing.
Dysfunctional breathing (disordered breathing, hyperventilation syndrome) is a condition with no accepted diagnostic criteria. It may be associated with anxiety disorders, co-exist with other cardio-respiratory disorders, or may have no associated co-morbidities. Dysfunctional breathing is characterised by an increase in minute ventilation (respiratory rate and volume each minute) that is disproportionate to the level of activity being undertaken, resulting in somatic and non-somatic symptoms.
The characteristic features of the dyspnoea are:
- Episodic nature
- May occur at rest or minimal exercise
- Occurs on exertion
- Often occurs when talking
- Air hunger
- Sensation of increased difficulty inhaling
- Sensation of needing to take ‘stretching breaths to fill the lungs’
Common associated symptoms include:
- Chest or throat tightness
- Peri-oral or carpal dysasthaesia
- Blurred vision
Less common associated symptoms include:
- Sense of doom
There are no conclusive laboratory tests available for the diagnosis of dysfunctional breathing, so diagnosis is made on clinical grounds. Dysfunctional breathing must always be considered as a diagnosis of exclusion. A careful history and examination should aim to rule out other possible – and potentially more serious – causes of breathlessness.
Differential diagnoses include:
- Heart failure
- Ischaemic heart disease
- Chronic obstructive pulmonary disease
- Pulmonary emboli
- Pulmonary fibrosis
Common diagnostic tests used for exclusion of other possible diseases include ECG, beta natriuretic peptide, spirometry, peak flow monitoring, pulse oximetry, and chest X-ray.
Voluntary hyperventilation may reproduce symptoms with ongoing involuntary hyperventilation, but the test has a low diagnostic sensitivity and specificity. In patients with suspected dysfunctional breathing, it may be of use demonstrating how their symptoms can be reproduced by asking them to breathe deeply.
For patients with suspected dysfunctional breathing, the Nijmegen questionnaire has good sensitivity and specificity.
Further specialist tests used include bronchial provocation testing, echocardiography, cardio-pulmonary exercise testing, and formal hyperventilation provocation test with CO2 monitoring.
However, these are predominantly used to exclude other diagnoses and clinical history – examination remains the key to diagnosis.
Education and cognitive behavioural therapies are the mainstays of treatment.
Many patients worry that they have significant underlying cardiorespiratory disease, and some will have had secondary care assessment without a positive diagnosis, thereby reinforcing their belief that ‘there must be something wrong but the doctors can’t sort it out’. This lack of diagnostic clarity may also reinforce their dysfunctional breathing pattern. Reassurance and a positive explanation of the relationship between all of their symptoms and disproportionate over-breathing may help some patients.
Cognitive behavioural therapy in the form of breathing retraining techniques is the mainstay of treatment.
Optimum treatment of any underlying psychological or underlying cardio-respiratory physical conditions is also essential.
There is little evidence for benefit from benzodiazepines, beta-blockers or antidepressant medications.
Dr Jonathan Bennett is a consultant respiratory physician and head of service at Glenfield Hospital