When is a Security patch not a patch?

I have a dilemma. I'm the IT Security dude. I'm responsible for filtering incoming security information (CERT announcements, vendor security patches, real threats, etc.) and doing an impact analysis on them.

Since our organization is very structured i.e. ITIL I then send my report to our Service Delivery team who is responsible for the hands on sysadmin.

So my dilemma is this. Management is now rethinking this approach (since the Service delivery folks are quite busy) and is expecting me to apply patches. My argument is that;
a) No one person can have the detailed knowledge of all the OS's we support (basically all OS's) to
be able to do this and;
b) That a security patch is just another patch, albeit more urgent than patches applied during the regular patch cycle.

To be frank, there is no patch management procedure in place at all. Patches are applied in an adhoc "as needed" basis.

So what to do? Can anyone offer any insight?

Please and Thanks,

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