The clue - "Cold month outside, regarding staff (7)". I have _C_P_R_ and I know it will be a slap-on-head moment when the answer is revealed. I feel that ice or icy must be in there somewhere!
Thanks for that - as the great man said - "D-oh"! No excuse I know, but I was thinking of trawling through "staff" in the Thesaurus and had a suspicion that "re" had to be in there somewhere. I should have persevered!