Medical Devices - Use and Safety by Bertil Jacobsen & Alan Murray published by Churchill Livingstone ISBN-13 978-0-443-10259-2 is an excellent book.
Similarly Ward's Anaesthetic Equipment, by Ward, Davey & Moyle Publisher: Saunders (W.B.) Co Ltd;ISBN-13: 978-0702014352. I had the privilege of working with the main author.
Brian