By "monitor" I am assuming that you wish to record a script where you are using a Lotus Client. To get some hints on the protocols you might try use the Protocol Advisor tool in VuGen.
If this is not what you meant by "monitor" could you please clarify your need?
Note that LoadRunner is intended to be used to load test server side components that a Lotus Client would connect to. However a VuGen script could be developed that would "simulate" a Lotus Client connection for use in a HP BSM/BPM environment.