Question: Our surgeon had to cancel a surgery midway through a procedure for the patient’s health. Are there any guidelines for whether I should use modifier 52 or 53 in this case? Oregon Subscriber Answer: Yes, you should apply modifier 53 (Discontinued procedure) for reporting terminated surgeries “due to extenuating circumstances or those that threaten the wellbeing of the patient,” according to the CPT® code book. Your example warrants the use of modifier 53. According to Appendix A in the CPT® code book, modifier 53 “is not used to report the elective cancellation of a procedure prior to the patient’s anesthesia induction and/or surgical preparation in the operating suite.” This means when reporting physician services, you may not bill for the surgical service in any capacity if the procedure is terminated prior to anesthesia. You may use modifier 52 (Reduced services) in a variety of contexts. “Modifier 52 can be used to identify the services were reduced from the full description of the procedure code or some components of it were not performed,” says Jennifer McNamara, CPC, CCS, CRC, CPMA, CDEO, COSC, CGSC, COPC, director of healthcare training and practice support at Healthcare Inspired LLC. Bella Vista, Arkansas. For instance, you can append it to surgical codes that are inherently bilateral but that your surgeon performs unilaterally. Modifier 52 is not the appropriate choice for your example. “When a procedure is not continued due to circumstances affecting the patient, it is also advisable to add ICD-10-CM code Z53.09-[Procedure and treatment not carried out because of other contraindication],” says McNamara.