f5 pool member LTM moniotring

Not sure about OID setting but can be achieve via $1 setting. This options is available to you, depend on the version of BIG-IP code which you are running. Under 11.x, following K3667:

https://support.f5.com/csp/article/K13180

This will email every time any member of any pool goes "down" or "up".

 alert BIGIP_MCPD_MCPDERR_POOL_MEMBER_MON_DOWN "Pool (.*?) member (.*?):(.*?) monitor status down." {
    email toaddress="receiver@yourcompany.com"
    fromaddress="root"
    body="A pool member went down"
}

alert BIGIP_MCPD_MCPDERR_POOL_MEMBER_MON_UP "Pool (.*?) member (.*?):(.*?) monitor status up." {
    email toaddress="receiver@yourcompany.com"
    fromaddress="root"
    body="A pool member came back up"
    }