What is a sleep study?
This is an overnight investigation of your breathing, heart rate, oxygenation and movements during sleep. It may also involve monitoring the stages of your sleep if necessary (polysomnography).
To carry out this study it is necessary to attach to you various pieces of recording equipment. A specially trained nurse will explain the procedure and attach the recording equipment.
Where does the study take place?
You sleep in a side ward of Ward 9, which is a medical ward. The study is overnight only – you can go home during the day, anytime after 6am.
It may involve one or two nights in hospital. You should wear ordinary night clothes, although you may be asked to wear a hospital gown. All equipment will be attached over clothes, on your finger, leg or face and head as necessary. You will be monitored on video.
What information is recorded?
- Pulse rate via a probe attached to your finger which also measures oxygen levels in your blood via pulse oximetry.
- Chest and abdominal movements during breathing via stretch bands around your chest and abdomen. This shows if your breathing is obstructed or if there are pauses in your breathing during your sleep.
- Airflow and snoring via a nasal cannula
- Leg movement – via a sensor attached to your legs.
- Body position – and overall movements via a video camera and/or position monitor.
- Sleep staging – via electrodes attached to your face and scalp. (This is not always necessary).
What happens to the information recorded?
All information is downloaded onto a computer to which the monitors are attached. This is then analysed later. The recordings generate a considerable amount of data which can take several days to analyse.
You will be given an outpatient appointment to discuss your results once they have been analysed. This will be sent to you in due course.
If you have any problems or questions during the study do not hesitate to call for assistance.
Sometimes the consultant may ask for a Tosca monitor to be undertaken. This is a recording of carbon dioxide levels in the blood. The test consists of an electrode being placed on the earlobe and is always carried out overnight as an inpatient. The information is downloaded the following morning for analysis.