High-Risk Surgeries According to the Revised Cardiac Risk Index (RCRI)
According to the Revised Cardiac Risk Index (RCRI), high-risk surgeries include intraperitoneal, intrathoracic, and suprainguinal vascular procedures. 1
Definition of High-Risk Surgeries in RCRI
The RCRI specifically classifies the following procedures as high-risk:
- Intraperitoneal procedures - surgeries within the abdominal cavity
- Intrathoracic procedures - surgeries within the chest cavity
- Suprainguinal vascular procedures - vascular surgeries above the inguinal ligament
These high-risk procedures represent one of the six independent risk factors in the RCRI for predicting major cardiac complications during noncardiac surgery 1.
Risk Stratification by Surgical Procedure
Different surgical procedures carry varying levels of cardiovascular risk:
High-Risk Procedures
- Open aortic and infrainguinal vascular procedures (highest risk)
- Major vascular surgeries
- Prolonged procedures with large fluid shifts/blood loss
Intermediate-Risk Procedures
- Carotid endarterectomy
- Head and neck surgery
- Intraperitoneal and intrathoracic procedures (when not classified as high-risk)
- Orthopedic surgery
- Prostate surgery
- Endovascular abdominal aortic aneurysm repair (lower risk than open repair)
Low-Risk Procedures
- Endoscopic procedures
- Superficial procedures
- Cataract surgery
- Breast surgery
- Plastic surgery 1
Clinical Implications
The risk of major adverse cardiac events (MACE) increases with the number of RCRI risk factors:
- 0 risk factors: 0.4-0.5% risk
- 1 risk factor: 0.9-1.3% risk
- 2 risk factors: 4-7% risk
- ≥3 risk factors: 9-11% risk 2
It's important to note that the RCRI has moderate discrimination ability (AUC 0.75) for cardiac events after mixed noncardiac surgery but is less accurate for vascular surgery patients (AUC 0.64) 3. The RCRI tends to underestimate cardiac complications in vascular surgery patients by 1.7 to 7.4-fold 4.
Important Considerations
- Emergency surgery significantly increases perioperative risk beyond what the RCRI predicts 2, 5
- Age is an independent predictor of perioperative risk, although not included in the RCRI 2
- The surgical approach can modify risk - for example, endovascular aortic aneurysm repair carries lower perioperative risk than open repair 1
- The latest guidelines suggest that an RCRI >1 or a calculated risk of MACE >1% should be used as a threshold to identify high-risk patients 2
Risk Reduction Strategies
For patients undergoing high-risk procedures with multiple RCRI risk factors:
- Consider preoperative cardiac evaluation
- Implement appropriate perioperative beta-blockade in selected patients
- Continue statins in patients already on them
- Consider initiating statins for vascular surgery patients at least 2 days before surgery
- Implement continuous cardiac monitoring during and after surgery
Remember that the RCRI is just one component of comprehensive preoperative risk assessment, and its limitations should be considered when evaluating patients for high-risk procedures.