What is the principal procedure?
The procedure that is performed for definitive treatment or is taking care of a complication is the principal procedure. Procedures for diagnostic or exploratory purposes that are performed in addition to a procedure being performed for definitive treatment, would be reported in addition to the principal procedure.
An example of definitive and diagnostic procedures being performed on the same admission would be: Patient is admitted with chest pain and this is worked up with cardiac catheterization/angiography. The patient is found to have significant coronary artery disease and is then scheduled for bypass surgery on the same date. In this case, the coronary artery bypass is the principal procedure as it is being performed for definitive treatment of the heart disease. The heart catheterization and angiography would be reported as additional procedures since they were diagnostic tests. Sometimes, there are only diagnostic/exploratory procedures performed. If this is the case, then one of these would be reported first.
In the example above the MS-DRG would be the same regardless of the sequencing, HOWEVER for consistency and accuracy in reporting data the coding guidelines should be followed.
ICD-10-PCS Official Guidelines for Coding and Reporting 2023 Page 20:
Selection of Principal Procedure
The following instructions should be applied in the selection of principal procedure and clarification on the importance of the relation to the principal diagnosis when more than one procedure is performed:
- Procedure performed for definitive treatment of both principal diagnosis and secondary diagnosis
a. Sequence procedure performed for definitive treatment most related to principal diagnosis as principal procedure.
- Procedure performed for definitive treatment and diagnostic procedures performed for both principal diagnosis and secondary diagnosis.
a. Sequence procedure performed for definitive treatment most related to principal diagnosis as principal procedure
- A diagnostic procedure was performed for the principal diagnosis and a procedure is performed for definitive treatment of a secondary diagnosis.
a. Sequence diagnostic procedure as principal procedure since the procedure most related to the principal diagnosis takes precedence.
- No procedures performed that are related to principal diagnosis; procedures performed for definitive treatment and diagnostic procedures were performed for secondary diagnosis
a. Sequence procedure performed for definitive treatment of secondary diagnosis as principal procedure since there are no procedures (definitive or nondefinitive treatment) related to principal diagnosis.
- Patient is admitted with respiratory failure and acute MI placed on mechanical ventilation. He also had PTCA with stent of the coronary artery. The principal procedure would be the PTCA/stent and not the mechanical ventilation. The PTCA/stent is considered definitive treatment and directed towards the PDX.
- Patient is admitted with GI bleeding and underwent colonoscopy to look for the etiology of the bleeding. The patient is found to have a bleeding sigmoid polyp that is biopsied and found to be positive for adenocarcinoma. The patient (during this same admission) is taken to surgery and resection of the sigmoid colon was performed. The principal procedure would be the sigmoid resection as this is the procedure that was completed for definitive treatment. The colonoscopy and biopsy would be reported as an additional procedure.
- Patient is admitted with acute CVA and this is found to be due to carotid artery occlusion. The patient is taken to surgery for endarterectomy of the carotid artery. The day following the procedure the patient is found to have suffered an acute MI after the surgery. The patient is worked up for this and coronary bypass was recommended. On this same admission, the patient does have coronary bypass. The principal procedure would be the carotid endarterectomy as this is the definitive procedure that is related to the principal diagnosis.
ICD-10-PCS Official Guidelines for Coding and Reporting 2022 Page: 19
AHA Coding Clinic®, Fourth Quarter 1990 Page: 5 to 6
AHA Coding Clinic®, Second Quarter 2011 Page: 3
HIA’s comprehensive auditing approach includes acute coding audits and Clinical Documentation Integrity (CDI) audits.
The information contained in this coding advice is valid at the time of posting. Viewers are encouraged to research subsequent official guidance in the areas associated with the topic as they can change rapidly.
Subscribe to our Newsletter
to our Newsletter
Weekly medical coding tips and coding education delivered directly to your inbox.