Recommended Preoperative Assessment Scoring Systems
The American Society of Anesthesiologists (ASA) Physical Status Classification is the most widely recommended scoring system for preoperative assessment, with additional specialized systems used based on specific clinical contexts. 1
Primary Recommended Scoring Systems
ASA Physical Status Classification
- Strongly recommended as the primary preoperative assessment tool due to its close correlation with perioperative mortality 1, 2
- Classifies patients from ASA I (healthy patient) to ASA VI (brain-dead patient) based on comorbidities and clinical characteristics 3
- Demonstrates moderate inter-rater reliability (κ 0.61) in clinical practice, with 98.6% of paired assessments being within one class of each other 4
- Correlates significantly with patient age, Charlson comorbidity index, and revised cardiac risk index 4
- Has moderate ability to predict in-hospital mortality and cardiac complications 5, 4
Revised Cardiac Risk Index (RCRI)
- Recommended for cardiac risk assessment in patients undergoing non-cardiac surgery 6
- Predicts risk of major cardiac complications including myocardial infarction, pulmonary edema, ventricular fibrillation, and complete heart block 6
- Stratifies patients into low risk (RCRI 0-1, <1% risk of major adverse cardiac events) and elevated risk (RCRI ≥2, ≥1% risk) 6
- Should be used as an initial screening tool before proceeding to more specialized cardiac testing 6
Specialized Assessment Tools
Nutritional Risk Screening
- For patients at risk of malnutrition, the Nutritional Risk Screening (NRS-2002) is recommended by the European Society for Clinical Nutrition and Metabolism 1
- Alternative validated tools include Subjective Global Assessment (SGA), Nutrition Risk Index, and Perioperative Nutrition Score 1
- These tools can predict risk of postoperative complications and prolonged hospital length of stay 1
Laboratory Testing Based on Risk Assessment
- Complete blood count (CBC) recommendations should be based on patient risk factors rather than routine testing for all patients 1
- CBC is recommended for patients with liver disease, extremes of age, history of anemia/bleeding, or hematologic disorders 1
- Electrolyte testing should be guided by history and physical examination findings rather than performed routinely 1
- Consider electrolyte measurement for patients taking digoxin, diuretics, ACE inhibitors, or ARBs 1
Implementation Considerations
Patient-Centered Triage Approach
- Patient-Centered Anesthesia Triage System (PCATS) can be used by non-clinical personnel to predict ASA status and appropriately triage patients for preoperative assessment 7
- PCATS criteria include number of prescription medications (≥5), BMI (>35), age (>80 years), and surgical complexity 7
- This system has high sensitivity (0.88) and specificity (0.74) for predicting ASA PS classification III or IV 7
Common Pitfalls to Avoid
- Relying solely on ASA classification as a predictor of operative risk without considering other factors such as procedural complexity, surgeon experience, and physiological support services 5
- Failing to have patients with ASA grade 3 or 4 consult with a senior anesthesiologist well before surgery, which can lead to day-of-surgery cancellations 5
- Using routine preoperative tests without clinical indications, which increases costs without improving outcomes 1
Special Considerations
Elderly Patients
- Consider more comprehensive assessment for patients >80 years of age, as this is an independent risk factor 1, 7
- ECG is recommended for patients older than 65 years 1
Cardiac Surgery Patients
- For cardiac surgery patients, the EuroSCORE (European System for Cardiac Operative Risk Evaluation) is recommended for risk stratification 1
- Preoperative B-type natriuretic peptide (BNP) levels >385 pg/ml are independent predictors of postoperative complications and mortality 1