Answer: No. You should include the conscious sedation in the procedure (45378, Colonoscopy, flexible, proximal to splenic flexure; diagnostic, with or without collection of specimen[s] by brushing or washing, with or without colon compression [separate procedure]).
CPT now contains a list of codes (see Appendix G in CPT - not all manual versions contain this appendix) that include conscious sedation as an inherent part of the service. Code 45378 (diagnostic colonoscopy) is among the codes on the new list that FPs use.
Tip: You can easily find out if a code includes conscious sedation by looking for a bulls-eye symbol next to the code. For codes so designated, you should not report both the service and one of the conscious sedation codes (99141 and 99142). Otherwise, you may separately report conscious sedation if the FP performs both the sedation and the procedure.