I've used Draeger's OneNet in the past as an example of the trend to greater integration of medical devices and hospital's overall IT environment. Well, I've dug up a few items that explain how it started and   First up is an article by Rhue and Maloney about their experience at Samaritan Medical Center, Watertown, NY. Here's how it all started:

In 1999, we purchased a wired monitoring system for
the ED from a business unit of Siemens Medical Solutions that later
became part of Dräger Medical of Telford, Pa. However, our long-term
plan was to improve upon our previous wireless monitoring system and
replace the wired system with wireless. Our previous wireless system
had used radio frequency (RF) transmission, and although the antennae
were correctly positioned throughout the ED and radiology, the lead
walls in the diagnostic area caused complete loss of signal when moving
patients into radiology rooms for X-rays and scans. The signal was also
subject to cellular phone and electrical equipment interference

When Dräger Medical came to install the wireless technology for ED
monitoring at Samaritan in 2003, they realized that there would be
duplication of the wireless access points that the hospital’s IT
department was already in the process of installing to support the
hospital information system (HIS). Everyone at SMC agreed that the
wireless initiative had to happen, but installing two wireless network
infrastructures would cause major problems.

This white paper (pdf) provides a more technical view of OneNet. And here's the press release announcing OneNet.

Traditionally, patient monitoring has required its own separate,
dedicated network in order to guarantee security and performance.
Infinity OneNet is Dräger Medical's innovative approach to implementing
“life critical” patient monitoring networks. Infinity OneNet is both a
network architecture and a comprehensive suite of professional services
that allows the hospital's existing enterprise network to provide
patient monitoring in parallel with its commercial and administrative
applications – all on one industry-standard network.

The press release also has a snazzy color graphic depicting a OneNet implementation here. More later.