Preoperative Risk Evaluation: An Old School ApproachWith a Few New Tools • David Chamberlain MD
What Causes Perioperative Mortality? 0.7 – 0.8% All cause (4,038 out of 485,850 pts) 1:2680 Anesthesia 1:420 Surgical error 1:95 Underlying medical condition(s) 67% Progression/complication of presenting disease 44% Progression/complication of underlying disease 30% Surgery contributed to mortality < 1/3 Cardiac > 1/3 Pulmonary 1/3 Other medical conditions Fleischer, L, J Am Soc Anesthesiology, May 2002,Vol 96, Issue 5, p.1039-1041
Are Internists Really Worth It? More likely to identify and intervene on medical conditions related to surgical outcomes. Devereaux, PJ, et al, Clin Invest Med 2000: 23:116 Decreased length of stay post thoracic and hip surgery. Phy, MP, et al, Arch Intern Med 2005; 165:796 No improvement of glucose control, perioperative Beta Blockers, DVT prophylaxis. Auerbach, AD, et al, Arch Intern Med 2007; 167:2338 Higher 30 day and 1 year mortality rate, but in multi-variable analysis consulted patients had a significantly higher disease burden. Rates similar when adjusted. Wijeysundera, DN, et al, Arch Intern Med 2010: 170:1365 No study has shown a decrease in perioperative mortality.
Preoperative Risk Evaluationan Old School Approach • Risk Assessment • Global Assessment of Risk • Cardiac Perioperative Risk • Goldman Risk Index, Functional capacity, Surgical risk • Pulmonary Perioperative Risk • Risk Factor Evaluation • DVT Risk • Risk Factor Evaluation • Endocarditis Risk • Sanford Guidelines • Risk from Medical Conditions • Risk from Medications
Global Assessment of Riskor“Looks good from door” • American Society of Anesthesiologists Preoperative Patient Classification • Created in 1941 • Purpose was to assess the degree of a patient’s “sickness” • NPV far exceeds PPV – better at defining healthy than incapacitated • Not originally intended to predict operative risk, but …… (millions of patients later)
ASA Patient Classification Class 48hr Mortality 1 Healthy 0.07% 2 Mild Systemic Disease 0.24% 3 Severe Systemic Disease, limits 1.4% activity, but not incapacitating 4 Incapacitating systemic disease, 7.5% which is a constant threat to life 5 Moribund, not expected to survive 34% 24 hours with or without surgery Emergent Surgery Risk Doubles
Who is Too Sick or the “Are You Nuts?” Assessment Predictors of Risk for MI, Heart Failure, Death • Unstable Coronary Syndrome angina, acute or recent MI • Decompensated Heart Failure new onset, worsening HF, NYHA Class IV • Significant Arrhythmias high grade AV block, symptomatic or new ventricular arrhythmia, tachycardia with rate > 100, symptomatic bradycardia • Severe Valvular Disease severe aortic stenosis, symptomatic mitral stenosis
Predictors of Risk • Any one has high positive predictive value for MI, Heart failure, Death • Risk and severity of complications likely greater than benefit of surgery • Recommend delay or cancel surgery unless emergent • Those patients removed from subsequent cardiac risk assessments ACC/AHA 2007 Guidelines on perioperative cardiovascular evaluation and care for non-cardiac surgery. J Am Coll Cardiol. 2007; OCT 23;50(17):e159-241
Cardiac Perioperative RiskUpdated Old School Tools • Revised Goldman Cardiac Risk Index • Functional Capacity • Risk Specific to Type of Surgery
Beyond the Goldman Cardiac Risk Index • 2893 patients • Elective non-cardiac surgery • Monitored for cardiac complications • MI • Pulmonary Edema • Ventricular Fibrillation • Cardiac Arrest • Complete Heart Block NOT all cause mortality Lee, TH, et al, Circulation 1999; 100:1043.
Six Independent Predictors of Major Cardiac Complications • High Risk Surgery • History of Ischemic Heart Disease History MI, History positive stress test, angina, using NTG, Pathologic Q Not History CABG or PTCA or Stent • History of Heart Failure • History of Cerebrovascular Disease • DM treated with insulin • Serum Creatinine > 2.0 • Lee, TH, Marcantonio, ER, Mangione, CM, et al, Circulation 1999; 100;1043
Revised Goldman Cardiac Risk Indexvs.Rate of Cardiac Death, MI, Cardiac Arrest Risk Factors Rate 95% CI No Risk Factors 0.4% 0.1 – 0.8% One Risk Factor 1.0% 0.5 – 1.4% Two Risk Factors 2.4% 1.3 – 3.5% Three Risk Factors 5.4% 2.8 – 7.9% Devereaux, PJ, Goldman, L, Cook, DJ, et al. CMAJ 2005; 173:627
Revised Goldman Cardiac Risk Indexvs. Cardiac Death, MI, Cardiac Arrest, Vfib, Pulmonary Edema, Complete Heart Block Risk Factors Rate Rate with Beta Blockers None 0.4 – 1.0% < 1% One to Two 2.2 – 6.6% 0.8 – 1.6% Three or More > 9% > 3% Auerbach, A, Goldman, L. Circulation 2006; 113:1361
Revised Cardiac Risk IndexMost Studied and Validated • Validated in Cohort of 1422 patients • Predictive value for cardiac complications and mortality significant in All types of non-cardiac surgery except AAA • Does Not Capture all-cause Mortality Ford, MK et al, Ann Intern Med 2010; 152:26 • Better Predictive Value than original Goldman Criteria or Detsky Modified Risk Index Lee, TH, et al, Circulation 1999: 100:1043 • Retrospective study; 663,665 pts; major non-cardiac Sx; 329 hospitals, 2000 – 2001 RCRI likely underestimates risk of cardiac complications Increased mortality without Beta Blockers Devereaux, PJ, Goldman,L, et al, CMAJ 2005; 173:627
Functional Capacityor “What’s the METs thing?” • 1 MET = 3.5 mL O2 uptake/KG per min • O2 uptake of a 40 y/o, 70 kg male sitting upright • Peak exercise capacity an independent predictor of all mortality in normals and subjects with cardiovascular dz < 5 METs : Poor Survival Prognosis (<50%) 10 METs : Medical therapy = CABG (>75%) >= 13 METs : Good Survival Prognosis (>90%) (either category, data points at 10 year, linear separation as early as 1 year) For each 1 MET there is a 12% improvement in survival Myers, J, et al, N Engl J Med 2002; 346;793
METs 1 2 3 4 5 6 7 8 9 10 12+ Can Complete Activity Without Stopping Sit upright Eat, dress, use toilet, make bed Walk around house, shower 1 flight stairs, walk up hill, 2 block @ 2mph Light house work, dust, wash dishes, golf, bowl 2 flights of stairs, walk on flat @ 4mph, Sex Scrubbing floors, weight lifting, moving furniture Broke the bed/neighbors called the cops sex Shovel snow Doubles tennis, swing dancing Recreational Sports: Singles tennis, soccer, basketball, skiing, jogging Competitive sports Specific Activity Scale
How does this relate to Surgery? • < 4 METs Significantly Increases Risk MI, HF, Arrhythmia regardless of Surgical Risk • Functional Capacity Complication Rate < 4 METs > 5% 4 – 10 METs 1 – 5% > 10 Mets < 1% Eagle, KA, et al, J Am Coll Cardiol, 2002; 39, 542-553
What about Surgery Specific Risk? Risk Cardiac death or nonfatal MI High > 5 % Intermediate 1 – 5 % Low Risk < 1 % Emergency 2 – 5 times the surgical risk Fleischer, LA, Beckman, JA, Brown, KA, et al, ACC/AHA 2007 Guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery. J Am Coll Cardiology 2007; 50:e159.
Surgery Specific Risk for Cardiac Death or Nonfatal MI High Risk ( > 5% ) Aortic, Major vascular, Cardiothoracic, Emergent, long with large blood loss/fluid shifts Intermediate Risk ( 1 – 5% ) CEA, Head, Neck, Intraperitoneal, Intrathoracic, Orthopedic, Prostate Low Risk ( < 1% ) Ambulatory surgery, Endoscopy, Superficial Procedure, Cataract surgery, Breast surgery
The New School Uses:2007 ACC/AHA Cardiac Evaluation and Care Algorithm • Step 1 Emergency Surgery • Step 2 Global Assessment of Risk Too Sick for Surgery • Step 3 Global Assessment of Risk Low Risk and Low risk Surgery • Step 4 Assess Functional Capacity • Step 5 Calculate RCRI and Surgical Risk Looks like the old school and the new school are the same school
Step 1 Need Emergent Sx? Step 2 Active Cardiac Condition? Yes Proceed to OR Post Op risk stratification Risk Factor Management Yes Evaluate and Treat Consider OR when stable Evaluating Cardiac Risk2007 ACC/AHA Algorithm
Step 3 Low Risk Surgery? Step 4 Good Functional Capacity? Step 5 Poor or Unknown Yes Proceed to OR Yes Proceed to OR Yes Compute RCRI Evaluating Cardiac Risk 2007 ACC/AHA Algorithm
Step 5 continued Zero Risk Factors 1 – 2 Risk Factors or 3 or more Risk Factors and Intermediate Risk Surgery Yes Proceed to Surgery Yes Proceed to OR Rate Control with Beta Blocker Consider Non-Invasive Cardiac Testing if will change management Evaluating Cardiac Risk2007 ACC/AHA Algorithm
Step 5 continued 3 or more Risk Factors And High Risk Surgery Yes Consider Non-Invasive or Invasive testing if will change management Rate control with Beta Blockers Evaluating Cardiac Risk2007 ACC/AHA Algorithm
Evaluating Pulmonary RiskIt’s No Longer Just a Guess Pulmonary Complications MORE COMMON than Cardiac Complications Cause Significantly LONGER Hospital Stays Lawrence, VA, Hilsenbeck, SG, et al. J Gen Intern Med 1995; 10:671 MOST COSTLY Complications Dimick, JB, Chen, SL, et al. J Am Coll Surg 2004; 199:531 Pulmonary Complications 6.8% across all types Sx Atelectasis, Pulmonary Infection, Prolonged Mechanical Ventilation, Respiratory Failure, Chronic Lung Disease Exacerbation, Bronchospasm Smetana, GW, Lawrence, GA, et al, Ann Intern Med 2006; 144:581
Patient Related Age > 50, 60, 70, 80 Chronic Lung Disease Asthma Smoking Heart Failure Albumin BUN Functional Dependence ASA Class >= 2 Qasam, A, et al, Ann Intern Med, 2006; 144:575 Odds Ratio of Complications 1.5, 2.28, 3.9, 5.63 2.36 Uncontrolled 3, Controlled 1 Current 5.5, 2 mo Cessation 1.26 2.93 2.53 2.29 Total 2.51 Partial 1.65 4.87 Predictors of Pulmonary Complications
Procedure Related Surgical Site Duration > 3 – 4 hr Type of Anesthesia Emergency Qasam, A, et al, Ann Intern Med, 2006, 144:575 Odds Ratio Upper Abdominal 2.8 2.14 General 1.83 vs. Spinal 2.21 Predictors of Pulmonary Complications
Other Conditions That May Require Special Attention • Obesity Inconsistent data • OSA Probable • Pulmonary HTN Probable, Limited data • URI Data limited, usually defer Sx Smetana, G, Ann Intern Med, 2006; 144:581
Recommendations for Assessment of Pulmonary Risk • History and Physical Exam • Identify Pulmonary Risk Factors • American Society of Anesthesiologists - Global Assessment of Pulmonary Risk • Arozulla Multifactorial Risk Index for Postoperative Respiratory Failure Smetana, G, et al, Ann Intern Med, 2006; 144:581
ASA Postoperative Pulmonary Complications Class Pulmonary Complications 1 Healthy 1.2% 2 Mild Systemic Disease 5.4% 3 Severe Systemic Disease, limits 11.4% activity, but not incapacitating 4 Incapacitating systemic disease, 10.9% which is a constant threat to life 5 Moribund, not expected to survive NA 24 hrs with or without surgery Qasim, A, et al. Ann Intern Med, 2006; 144:575-580
Type of Surgery AAA Thoracic Neurosurgery, Upper Abdominal PeripheralVascular, Neck Emergency Surgery Albumin < 3.0 g/dL BUN > 30 mg/dL Partial/Full Dependence History of COPD Age > 70 Age 60 - 69 Point Value 27 21 14 11 9 8 7 6 6 5 Arozullah Respiratory Failure Risk Index
Arozullah Respiratory Failure Index Scoring Class Point Total % Respiratory Failure One <= 10 0.5 Two 11 – 19 1.8 Three 20 – 27 4.2 Four 28 – 40 10.1 Five > 40 26.6 Arozullah, AM, Daley, J, et al, Ann Surg 2000; 232:242
Put It All Together Step 1 ASA 1 and To OR Low Risk Arozulla 1 Step 2 ASA 2 or Consider Further Testing Arozulla 2 - 3 CXR, PFT if will change management. Step 3 ASA >= 3 or Reconsider Surgery High Risk Arozulla >= 4 Shorter Procedure Spinal or Epidural For all: Deep Breathing Exercises/Incentive Inspirometry Treat Identified Risk Factors & “Special” Conditions Smetana, G, et al, Ann Intern Med, 2006; 144:581
What Works Pre-op Asthma Evaluation Aggressive Tx. For COPD Inspiratory Muscle Training Pre-op Patient Education Selective Post-op NG decompression Median Length of Stay 1 day shorter Complication rate vs controls 18% vs.35% Hulzebos, EH, et al, JAMA, 2006; 296:1851 What Doesn’t Smoking Cessation Pre-op Antibiotics Tube Feed or TPN Strategies to Reduce Postoperative Pulmonary Complications
DVT Risk • Low Risk ( < 2% ) Age < 40 and Duration < 60 min and No Risk Factors Calf DVT 2% Proximal DVT 0.4% Significant PE 0.2% Fatal PE < 0.01% Tx: Ted Hose, early ambulation • Moderate Risk ( 10 – 40% ) Age 40 – 60 or Duration > 60 min or Risk Factor Calf DVT 10 – 20% Proximal DVT 2 – 4% Significant PE 1 – 2% Fatal PE 0.1 – 0.4% Tx: LMWH, SCD Additional Risk Factors: Advanced Age, Cancer, Prior Venous Thromboembolism, Obesity, HF, Paralysis, Hypercoagulable State
DVT Risk • High Risk ( 40 % ) Age > 60 Age 40 – 60 With Additional Risk Factor Calf DVT 20 – 40% Proximal DVT 4 – 8% Significant PE 1 – 2% Fatal PE 0.4 – 1.0% Tx: LMWH, SCD, Consider Prolonged Anticoagulation • Highest Risk ( 40 – 80% ) Age > 40 with Multiple Additional Risk Factors or THR, TKR, Hip Fracture, Major Trauma, Spinal Cord Calf DVT 40 – 80% Proximal DVT 10 – 20% Significant PE 4 – 10% Fatal PE 0.2 – 5% Tx: Long Term LMWH/Anticoagulation, Vena Caval Interruption Geerts, WH, et al, Chest 2004; 126:3385
Column A: Procedure Dental Skin and Soft Tissue Infection Respiratory AHA, April 2007 Column B: Abnormality Prosthetic Cardiac Valve History of Endocarditis Congenital Heart Disease Unrepaired Cyanotic Repaired <= 6 months Cardiac Transplant Valvulopathy Endocarditis ProphylaxisOne from Column A and Column B
Endocarditis Prophylaxis • None for GI • None for GU • None for MVP • None for ASD AHA, April 2007 • None for bad hair day
Medication ConsiderationsAspirin and Clopidogrel • When possible delay non-cardiac surgery in patients with recent coronary stenting • 4 to 6 weeks for bare metal stent • At least 12 months for drug-eluting stent • Optimize antiplatelet therapy with aspirin and clopidogrel by continuing it or reinstating it ASAP after procedure Fleischer, L, et al, Circulation, 2007, 118:418 MKSAP Item 95, ACP IM Board Review Course October, 2010 I’m not saying this was on the IM Boards, but it sure does come up a lot lately. You didn’t hear nothing from me.
Medication Considerations andSpecific Medical Conditions Expertise comes from residency and years of clinical experience. We are the experts in these areas. Consider assuming care. This is where an Internist is really worth it.