A patient support apparatus includes a frame, patient support surface, clock, transceiver, and controller. The transceiver communicates with a headwall and/or a local area network. The controller detects the occurrence of an event and sends a message to a server in communication with the local area network in response to the event. The controller updates its estimate of the local time based upon time data received from the server. The controller may also and/or additionally receive first and second time updates from two different sources. When received, the controller updates its estimate of local time based upon at least one of the following: (a) a comparison of its estimate of local time with the time data from the first source； and (b) a comparison of its estimate of local time with the time data received from the second source.
