The Royal Papworth Hospital is currently missing more than 100 overnight sleep study devices (known as CSS equipment).
The devices are provided to patients for a single, overnight study, and should be returned promptly to the hospital the following day.
When the devices are not returned, it means that the hospital has to cancel appointments for other patients.
It also means that vital treatment decisions are delayed, and NHS resources are wasted.
The hospital is down from 220 devices to 73, meaning more than 1,000 patients a year may miss out on timely care.
A spokesperson for the hospital said: “We understand life sometimes gets in the way of things like this and the purpose of this isn’t to apportion blame, but to simply remind people who may have one sitting on the side or hiding away somewhere.
“So please, if you or someone you know still has one of these sleep study devices, return it to us as soon as possible.
“If you have any issues with returning equipment, please call our team during the daytime on 01223 638526 who will be happy to help.”
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