|
Appendix D MS-DRG Surgical Hierarchy by MDC and MS-DRG |
Since patients can have multiple procedures related to their principal diagnosis during
a particular hospital stay, and a patient can be assigned to only one surgical class, the
surgical classes in each MDC are defined in a hierarchical order. Patients with multiple
procedures are assigned to the highest surgical class in the hierarchy to which one of
the procedures is assigned. Thus, if a patient receives both a D&C and a
hysterectomy, the patient is assigned to the hysterectomy surgical class because a
hysterectomy is higher in the hierarchy than a D&C. Because of the surgical hierarchy,
ordering of the surgical procedures on the patient abstract or claim has no influence
on the assignment of the surgical class and the MS-DRG.
The surgical hierarchy for each MDC reflects the relative resource requirements of
various surgical procedures. In some cases a surgical class in the hierarchy is actually
an MS-DRG. For example, Arthroscopy is both a surgical class in the hierarchy and
MS-DRG 509 in MDC 8, Diseases and Disorders of the Musculoskeletal System and
Connective Tissue. In other cases the surgical class in the hierarchy is further
partitioned based on other variables such as complications and comorbidities, or
principal diagnosis to form multiple MS-DRGs. As an example, in MDC 5, Diseases
and Disorders of the Circulatory System, the surgical class for permanent pacemaker
implantation is divided into three MS-DRGs (242-244) based on whether or not the
patient had no CCs, a CC or an MCC.
Appendix D presents the surgical hierarchy for each MDC. Appendix D is organized
by MDC with a list of the surgical classes associated with that MDC listed in
hierarchical order as well as the MS-DRGs that are included in each surgical class. The
names given to the surgical classes in the hierarchy correspond to the names used in
the MS-DRG logic tables and in the body of the Definitions Manual.