Jason E. Davis, MD

PERI-OPERATIVE CARDIAC RISK

REDUCTION, A-FIB/MI MANAGEMENT

~27 million non-cardiac surgeries per year1 – 1.5 million for pt’s w/ known cardiac disease3 – 4 million for pt’s with 3 or more risk factors for coronary

artery disease (DM, smoking, etc)Past 50 years in surgery

Dramatic changes in procedures Improvements to survival

SURGERY AS A CONTROLLED INJURY

Predictable responses Body doesn’t differentiate surgery from injury

Fight or flight, mobilization of energy stores

“Physiological Narrowing” 20 years old and healthy generally tolerates stressors better than

pt 80 years oldGraded neuro-endocrine response

Bigger surgery, bigger response

SURGERY AS A CONTROLLED INJURY

• Anterior Pituitary– ACTH– Growth hormone– Prolactin– Endorphin

• Posterior Pituitary– Arginine vasopressin

• Adrenals– Cortisol– Epinephrine (rises until 3 hrs)– Norepinephrine (until 3 days)

PREDICTABLE RESPONSES

AnalgesiaHypercoagulability (control of blood loss)Mobilization of metabolic substrates (glucose)Conservation of fluid, electrolytes

POST-INJURY/SURGERY DEFENSES

• Altered hemodynamics– Hypertension– Fluid and metabolite shifts– Tachycardia– Hypercoagulability– DVT, pulmonary embolus–Myocardial Ischemia– Congestive heart failure– Tachyarrhythmia• Hypokalemia• Hypomagnesemia• Immune suppression• Infectious complications• Hyperglycemia

CONSEQUENCES & COMPLICATIONS

Defining overall riskPMH = Opportunity to Prevent, Plan, AdaptHighest risk for complications

First 3 days post-operatively Corresponds to injury + response

SEQUENCE OF EVENTS

American Society of Anesthesiologists risk stratification and classification scheme Class 1: Normal healthy patient Class 2: Patient with mild systemic disease Class 3: Severe systemic disease, limits function Class 4: Incapacitating, constant threat to life Class 5: Moribund, unlikely to survive +/- surgery Class 6: Brain-dead organ donor

PATIENT SELECTION

American Society of Anesthesiologists risk stratification and classification scheme Class 1: Mortality 0 – 2% Class 2: Mortality 0.5 – 3% Class 3: Mortality 5 – 10% Class 4: Mortality 75%

Elective vs. Emergent: 2 – 3x riskAlso: Magnitude, Duration…

PATIENT SELECTION

High Risk factors Acute/recent MI Unstable coronary dx De-compensated CHF Significant arrhythmias Severe valvular disease

EAGLE’S CARDIAC RISK ASSESSMENT HTTP://WWW.FPNOTEBOOK.COM/CV/SURGERY/EGLSCRDCRSKASMNT.HTM

Intermediate Risk factors Mild angina History of MI, compensated CHF Renal insufficiency, DM

Minor Risk Factors Advanced age Abnormal EKG Low functional capacity

EAGLE’S CARDIAC RISK ASSESSMENT HTTP://WWW.FPNOTEBOOK.COM/CV/SURGERY/EGLSCRDCRSKASMNT.HTM

• Eagle’s cardiac risk assessment–>70 years age– History of angina– History of ventricular dysfunction– Diabetes on therapy– Abnormal Q-waves on EKG

• ACC-AHA Criteria– Functional Capacity (I – IV)– Graded by “Metabolic Equivalents” (>4 METS = lower risk)

• Detsky’s Modified risk index• Goldman criteria

FURTHER PRE-OP PLANNINGHTTP://WWW.FPNOTEBOOK.COM/CV/SURGERY/ACAHPRPRTVCRDCRSKASMNT.HT

M

• Beta-Blockers– Chronic users (AM w/ sip of water)– High risk non-users prescribed pre-op• Remember neuro-endocrine response

• Anticoagulants – soon as outweighs bleeding– Coumadin• Interim heparin

– Aspirin, Plavix

• Statins – mixed literature

CONTINUATION OF MEDICATIONS

• Pre-operative– Pre-emptive anesthesia (local, systemic)– Appreciate pt’s entire risk -- not just surgical!

• Intra-operative– Product of underlying problems x surgical stress

• Post-operative– Pain control– Fluid balance, early mobilization– Tx co-morbid conditions

ATTENUATION OF STRESS RESPONSE

• Anesthetic selection– Local +/- sedation– Regional (epidural, spinal, etc)– General

• Temperature control– National initiatives to 37C• Improved bloodflow• Decreased neuro-endocrine

ANESTHETIC FACTORS(COLLABORATIVELY ADDRESSED WITH ANESTHESIA

COLLEAGUES)

• Recognition– Irreg rhythm, tachycardia +/- CP, SOB, hypotension

• Diagnosis– EKG, new onset often secondary to ischemia

• Treatments– Attempt to normalize• B-blocker > Diltiazem > Digoxin

– Rate control (often same meds)– Anticoagulation soon as poss• Prevent propagation thrombus

ATRIAL FIBRILLATION

Recognition Tachycardia, hypotension, chest pain, new onset a-fib, shortness

of breath, mental status changeDiagnosis

EKG, Troponin/CKMb, CXR (assess alt causes)Treatment

B-blocker, nitrates, heparin, morphine, asa, statins Cardiology consult PRN

MYOCARDIAL ISCHEMIA

Lehigh Valley Heart Specialists Nurse available on-call Contact:

Lehigh Valley Heart Care Group Fellow available on-call Contact:

LVHN CARDIOLOGY CONSULTS

Consider whole pt Surgery (controlled injury) + co-morbidities

Risk reduction Pt stratification Clearance, medications Coordination of care

MI: dx, decrease work, decrease pain, +O2A-fib: ‘break’, rate, anticoag.

SUMMARY

THANK YOU.