What should you know about onyx pulse oximeter?

The sensor shines light through a finger and displays an estimate of oxygen saturation and pulse rate. A cold hand, movement, nail products, poor circulation, or an incorrectly positioned sensor can affect the display. One number is not a diagnosis, and a normal-looking reading does not explain breathlessness, chest pain, or confusion.

Sit quietly, warm your hand, remove nail coverings if practical, and place the device securely on a finger. Keep still until the number settles, then note the reading, time, and your symptoms. Repeat an unexpected result after checking the fit. Use the instructions supplied with your model and never use the device to delay needed care.

Seek urgent medical help for severe breathing difficulty, blue or grey lips, fainting, new confusion, or severe chest pain, regardless of the displayed number. Contact a clinician promptly if readings are repeatedly lower than your usual level or symptoms are worsening. A GP consultation can place the result in context and decide whether examination or testing is needed.

Ask what range is usual for you, how often to measure, which symptoms override the reading, and how to record results. Show the device and explain when the reading was taken, including whether you were resting or moving.