Lung Function Laboratory

The lung function unit is an integral part of the department of Thoracic Medicine, offering a wide range of physiological tests to both inpatients and clinic outpatients within the Trust, to help not only in the diagnoses of lung disorders, but also to assess the severity of these conditions.

Tests performed

  • Simple Spirometry
  • Flow Volume Loop
  • Diffusing Capacity (Gas Transfer) Measurement
  • Lung Volume Measurement by Body Plethysmography or Helium Dilution
  • Airway Reversibility Assessment with Bronchodilators
  • 6 minute Walk Test
  • Skin prick allergy testing
  • Sleep Study Tests
  • CPAP service
  • Full Apnoea Screen
  • Maximal Inspiratory/Expiratory Pressures

All requests for lung function tests are made from within the Trust either from outpatient clinics or from physicians looking after inpatients.

Sleep service

If you have had difficulty getting off to sleep, staying asleep, it is recommended you consider completing the online course at before having your sleep study. Naturally improvements to sleeping habits take time to adjust.

If you are unable to access this locally you can self-refer to the IAPT is a service that offers brief CBT-based interventions (including CBT for insomnia). Please visit the Talk Changes website if you live in Hackney (alternatively, you can call 020 7683 4278)

Respiratory polygraphy

If the doctor suspects you may have sleep disordered breathing, you may be asked to undertake a sleep study. This involved a night sleeping with sensors attached to your body to monitor your breathing throughout the night. It is important that you avoid caffeine 24 hours before your sleep study to improve the chance of sleeping.

For help in setting up the home sleep study please watch this video

Sleep apnoea Treatment

CPAP therapy set up
Not everyone requires CPAP therapy to manage sleep apnoea. For those that do, it is important to allow for time to adjust to therapy. This new routine takes about two weeks to adopt. It is most important you use CPAP every night during this period to become accustomed to it.

In order to keep our patients safe and reduce the risk of COVID 19 infection, we have opted to provide a remote service delivering and servicing CPAP therapy. We will be instructed where to collect the CPAP unit and a mask. There will be a virtual troubleshooting video line should you have any difficulties which can be arranged by emailing

This video will help you with the CARA Mask

This video below will help you apply the F&P mask

CPAP machine

Click here for a simple set up guide

This video describes advanced features

This video shows how to clean and maintain

Getting help with CPAP issues

If you are experiencing claustrophobia with CPAP therapy you can find useful tips and support with the sleep –apnoea trust.
If you have a faulty machine or need some further assistance with your equipment please ring the respiratory lung function department on 02085107803 or email

Tips for coping with CPAP claustrophobia
Claustrophobia is a common feeling when starting CPAP therapy. This is often due to the unusual feeling of the mask on the face or discomfort generated during therapy of the pressure needed to keep the airway open.
We would recommend the following tips for coping with CPAP Claustrophobia:

  • Try desensitising yourself by wearing the mask while awake. Using it for an hour or two whilst reading or watching Television in the afternoon can help you get use to wearing the CPAP mask and pressure involved.
  • Use the machine regularly in order to establish a routine to help with coming to terms with the fear of using it and to acclimatise yourself to this. This often takes a minimum of 2 weeks.
  • Use the ramp facility to help with the pressure effects when falling asleep. Our sleep technician can help with this.
  • Join a support group ( or