Preoperative Risk Assessment

On this page

Preoperative Risk Assessment - Risk Riddle Kickoff

  • Goal: Identify patient & procedural risks; optimize patient condition; plan perioperative care.
  • Key Components: History (comorbidities, medications, allergies, anaesthetic history), physical exam, targeted investigations.

ASA Physical Status Classification System

ASA ClassDescriptionMortality Risk (Approx.)
ASA INormal healthy patient0.05%
ASA IIMild systemic disease0.4%
ASA IIISevere systemic disease4.5%
ASA IVSevere systemic disease, constant threat to life23%
ASA VMoribund, not expected to survive without operation51%
ASA VIDeclared brain-dead, organ donor-
EEmergency surgery (added to class)Doubles risk
  • Focus: Cardiovascular, respiratory, renal, endocrine, & hematologic systems.
  • Consider: Functional capacity (METs - Metabolic Equivalents of Task). <4 METs indicates poor functional capacity. 📌 METs Mnemonic: 1 MET = At rest; 4 METs = Climb 1-2 flights of stairs; >10 METs = Strenuous sports.

Preoperative Risk Assessment - Heart Smart Checkup

  • Goal: Identify & quantify cardiac risk before non-cardiac surgery.
  • Key Components:
    • Clinical Evaluation: Focused history (chest pain, dyspnea, syncope) & physical exam.
    • Functional Capacity (METS):
      • Crucial predictor. METS < 4 (e.g., can't climb 1 flight of stairs) = Poor capacity, ↑ risk.
      • METS ≥ 10 (e.g., strenuous sports) = Excellent. METS Score Examples for Preoperative Risk Assessment levels activities chart)
    • Revised Cardiac Risk Index (RCRI): 📌 "I-CHEST-C" (factors: Insulin Rx, CHF, High-risk surgery, Elevated Creatinine >2mg/dL, Stroke/TIA, Ischemic hearT disease/CAD).
      • 1 point per factor.
      • MACE Risk: 0 pts (0.4%), 1 pt (0.9%), 2 pts (6.6%), ≥3 pts (11%).
  • Baseline ECG: For age >40 with risk factors, or known cardiac disease.

⭐ An RCRI score of 0 indicates low risk (0.4% MACE), while a score of ≥3 indicates high risk (11% MACE) for major adverse cardiac events.

Preoperative Risk Assessment - Breath & Beyond Prep

  • Pulmonary Risk:
    • ARISCAT Score (PPCs): Age, SpO2 (<96%), Resp. infection (last month), Anemia (Hb <10 g/dL), Incision (thoracic/upper abd), Surgery duration (>2h), Emergency.
    • Smoking: Stop 4-8 weeks pre-op.
    • FEV1 <1L or <30% predicted = high risk.
  • Renal Risk:
    • Assess baseline eGFR/Cr. Serum Cr >2 mg/dL ↑ risk.
    • ESRD: Dialysis within 1 week pre-op.
  • Hepatic Risk:
    • Child-Pugh Score: A (mortality 10%), B (30%), C (~75-80%).
    • MELD Score >15: High risk.
    • Acute liver failure: Contraindication.
  • Endocrine Risk:
    • Diabetes: HbA1c <8%. Target BG 140-180 mg/dL. Hold oral agents, adjust insulin.
    • Thyroid: Ensure euthyroid state.
    • Adrenal insufficiency: Stress dose steroids (e.g., Hydrocortisone 100 mg IV for major surgery).

⭐ Patients on chronic steroids (>5mg prednisone/day for >3wks) need stress dose steroids perioperatively to prevent adrenal crisis.

Preoperative Risk Assessment - Pill Plan & Shield Up

  • Pill Plan (Medication Management):
    • Anticoagulants:
      • Warfarin: Stop 5 days (INR <1.5). Bridge if high risk.
      • DOACs: Stop 24-72h (renal/drug dep.).
      • Aspirin: Continue (stents); stop 7d if high bleed risk.
      • Clopidogrel: Stop 5-7 days.
    • Diabetes: Metformin hold AM; adjust insulin (½ basal).
    • Antihypertensives: Continue β-blockers. Hold ACEi/ARBs AM.
    • Steroids: Stress dose (Hydrocortisone 100mg IV) if >5mg pred >3wks.
  • Shield Up (Prophylaxis):
    • SSI: Antibiotics (Cefazolin) 30-60m pre-incision.
    • VTE: Risk-stratify (Caprini); LMWH/SCDs.
    • Aspiration: PPI/H2RA if high risk (GERD, emergency).

⭐ Continue β-blockers in chronic users to prevent MACE (Major Adverse Cardiac Events).

High‑Yield Points - ⚡ Biggest Takeaways

  • ASA classification is paramount for overall perioperative risk stratification.
  • RCRI predicts cardiac risk; key factors include IHD, CHF, CVA, DM (insulin), Cr >2, high-risk surgery.
  • Functional capacity <4 METS signifies poor prognosis and ↑ surgical risk.
  • Advise smoking cessation at least 4-8 weeks before surgery to reduce pulmonary issues.
  • Optimize glycemic control (HbA1c ideally <7%) in diabetic patients preoperatively.
  • Careful management of anticoagulants/antiplatelets, often requiring bridging, is essential.
  • Child-Pugh score is used to assess risk in patients with liver cirrhosis.
Rezzy AI Tutor

Have doubts about this lesson?

Ask Rezzy, our AI tutor, to explain anything you didn't understand

Practice Questions: Preoperative Risk Assessment

Test your understanding with these related questions

Which pre-operative investigation is recommended before surgical procedures in a patient on warfarin therapy?

1 of 5

Flashcards: Preoperative Risk Assessment

1/10

In a _____ position, the patient's head is elevated 15 - 30 degrees higher than the feet.

TAP TO REVEAL ANSWER

In a _____ position, the patient's head is elevated 15 - 30 degrees higher than the feet.

reverse trendelenberg

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

Start For Free
Preoperative Risk Assessment - Free Indian Medical PG