CCDS Principal Procedure Selection and MS-DRG 5 — Questions and Answers
Question 1: A patient undergoes percutaneous transluminal coronary angioplasty (PTCA) with stent placement and also receives a pacemaker insertion during the same admission. How does this affect MS-DRG assignment?
- Only the pacemaker insertion is used because it has the higher relative weight
- Both procedures are coded; the grouper selects the DRG that optimally captures the resource use (Correct answer)
- PTCA takes precedence because it was performed first
- The two procedures cancel each other out and a medical DRG is assigned
Correct answer: Both procedures are coded; the grouper selects the DRG that optimally captures the resource use
The MS-DRG grouper evaluates all coded OR procedures and assigns the DRG combination that best reflects the resource intensity of the admission.
Question 2: Under ICD-10-PCS, what distinguishes 'Fusion' from 'Arthrodesis' in spinal procedure coding?
- Fusion is an obsolete root operation replaced by Arthrodesis in ICD-10-PCS
- ICD-10-PCS uses 'Fusion' as the root operation; 'Arthrodesis' is the clinical term for the same concept (Correct answer)
- Fusion applies to cervical spine only; Arthrodesis applies to lumbar spine
- Fusion involves implantable devices while Arthrodesis does not
Correct answer: ICD-10-PCS uses 'Fusion' as the root operation; 'Arthrodesis' is the clinical term for the same concept
In ICD-10-PCS the official root operation is Fusion; 'arthrodesis' is the clinical/surgical synonym that maps to the Fusion root operation.
Question 3: A patient is admitted for sepsis and undergoes incision and drainage (I&D) of an abscess on the right thigh. The sepsis is identified as originating from the abscess. What is the principal procedure?
- Blood cultures, as they identify the causative organism
- Incision and drainage, as it treats the source of the principal diagnosis (Correct answer)
- Intravenous antibiotic administration, as it treats sepsis directly
- No procedure qualifies as principal when the admission is for sepsis
Correct answer: Incision and drainage, as it treats the source of the principal diagnosis
The I&D treats the underlying source of the sepsis (the principal diagnosis), making it the principal procedure.
Question 4: Which ICD-10-PCS device character is used when a synthetic substitute mesh is placed during a ventral hernia repair?
- Autologous tissue substitute (7)
- Synthetic substitute (J) (Correct answer)
- Nonautologous tissue substitute (K)
- No device (Z)
Correct answer: Synthetic substitute (J)
Synthetic substitute (character J) is used in ICD-10-PCS when a synthetic mesh or other man-made material is placed during repair.
Question 5: The MS-DRG system groups cases into Major Diagnostic Categories (MDCs) primarily based on which factor?
- The patient's age and sex
- The principal diagnosis (Correct answer)
- The principal procedure
- The discharge disposition
Correct answer: The principal diagnosis
MDC assignment is driven by the principal diagnosis, which determines the body system or disease category for the case.
Question 6: A CDS notices that a physician documented 'lysis of adhesions' performed incidentally during an abdominal hysterectomy. Should lysis of adhesions be coded as a separate procedure?
- Yes, always code all procedures performed
- No, integral steps of a principal procedure are not coded separately per ICD-10-PCS guidelines (Correct answer)
- Yes, but only if it adds more than 30 minutes to operative time
- Only if the adhesions are listed in the final diagnosis
Correct answer: No, integral steps of a principal procedure are not coded separately per ICD-10-PCS guidelines
ICD-10-PCS instructs coders not to separately code procedures that are integral to completing the principal procedure.
Question 7: How does the presence of a Major Complication or Comorbidity (MCC) most directly affect MS-DRG assignment compared to the presence of a CC?
- MCCs shift the case to a higher-severity DRG with a greater relative weight than a CC would (Correct answer)
- MCCs and CCs affect the same DRG subgroup and differ only in reimbursement rate
- MCCs eliminate the need to code a principal procedure
- MCCs apply only to medical DRGs, not surgical DRGs
Correct answer: MCCs shift the case to a higher-severity DRG with a greater relative weight than a CC would
MS-DRGs are subdivided into three severity levels—with MCC, with CC, and without CC/MCC—and the MCC subgroup carries the highest relative weight.
CCDS Principal Procedure Selection and MS-DRG 5
A patient undergoes percutaneous transluminal coronary angioplasty (PTCA) with stent placement and also receives a pacemaker insertion during the same admission.
How does this affect MS-DRG assignment?