PRE-OP Evaluation IN PATIENTS WITH CVS DS for non- cardiac surgery.

1. MODERATOR- DR. DARA SINGH PRESENTED BY- DR. ANUPAM PRE-OP Evaluation IN PATIENTS WITH CVS DS for non- cardiac surgery.

2. PURPOSE OF PRE-OP EVALUATION • To identify the patients at risk for peri-op cardiac complications. • To evaluate the severity of underlying ds and if necessary implement measures to prepare high risk patients for non-cardiac surgery. • To stratify the extent of risk and determine the need for pre-op interventions to minimize the risk of periop cardiac complications . • To take informed consent. • Rapport establishment.

3. HISTORY:- • Presence ,severity & reversibility of CAD 1) risk factors 2) active cardiac condition 3) previous MI, prior cardiac evaluation 4) past interventions – CABG,PTCA,PM 5) functional capacity ( NYHA) 6) co-morbid conditions 7) dysrhythmias • In Valvular heart diseases – dyspnoea on minimal exertion, orthopnea, PND, embolic events, arrhythmias.

6. Medications – history, current medication, effectiveness. • History of any ppt factor. • Asthma, epilepsy, drug allergy, egg allergy, past surgery- type of anesthesia, any event, post op complication. • Loose tooth,denture.

7. EXAMINATION:- • VITALS • GPE – pallor, cyanosis, JVP, PE • CVS examination- displaced apical impulse, parasternal heave, thrill, palpable P2, S3 gallop ( LVEDP) , S4 ( decrd compliance/ LVH ) • Resp examination – b/l air entry, added sounds, pulmonary edema, pleural effusion. • Abd examination – signs of HF • Airway assessment – affected in diabetic pts.

8. Peripheral venous access • Spine examination • Neck movement.

9. LAB EVALUATION- • CHG – Hb, TLC,DLC, Hct, platelet count • FBS • LFT,RFT with electrolytes. • URINE-routine and microscopy. • CULTURES in I/E • CXR , ECG • ASO titers • CRP • Coagulation profile

10. CXR :- • Cardiomegaly • Signs of LV dysfxn- incrsd pul vascular markings, pul edema, pleural effusion • Pacemaker, ICD can be seen • PAH

11. ECG- • CAD- in old MI ,inverted t-wave, prominent and deep Q-wave, location • dysrythmias • Conduction defects • Digitalis toxicity-inverted T-waves , downward sloping of ST segment, narrow QRS complexes, atrial fibrillation, PAT wid 2 degree AV block is pathagnomic of • Chamber enlargement like LVH in hypertensive patients. • Electrolyte imbalance • AMBULATORY ECG monitoring-Confirms whether patients' symptoms are coincident with cardiac arrhythmia, e.g. ventricular ectopic beats or atrial fibrillation ( palpitation)

12. DETERMINATION OF RISK LEVEL in cardiac patients for non -cardiac surgeries : • Physical status classification(ASA) • Cardiac risk index ( Goldman) • Revised cardiac risk index ( Lee’s ) • Eagle criteria • ACC/AHA guidelines 2007

13. ASA CLASSIFICATION- toassess pts over all physical status • 1)normal healthy patient. • 2)mild systemic disease not limiting functional activity • 3)severe systemic disease that limits the activity bt not incapacitating. • 4)incapacitating disease that is a constant threat to life • 5)moribund patient who is not going to survive for >24 hrs with or without operation. • 6)brain dead patients. • E = emergency procedure.

14. Cardiac Risk Index • History - Age over 70 MI within 5 months • Physical - JVP or S3 Significant aortic stenosis • EKG - Rhythm other than sinus or PACs More than 5 PVC/min • General - pO2 < 50, pCO2 > 50 K+< 3, bicarb < 20 BUN > 50, Cr > 3 • Elevated ALT or chronic liver disease • Bedridden from non-cardiac causes • Procedure - Emergency Aortic, Intrathoracic or intraperitoneal

15. REVISED CARDIAC RISK INDEX 6 independent predictors • High risk surgery • Ischemic heart disease • Heart failure • Cerebro-vascular disease • Pre-op treatment with insulin • Pre-op Cr over 2 mg/dl Rate of major cardiac complications- 0 – 0.5 % 1- 1.3% 2 – 4% >3 – 9 %

16. ACC/AHA GUIDELINES 2007 • Evaluate urgency of surgery • Cardiac history and previous evaluation • Clinical predictors • Functional capacity • Surgical risk • Tests to determine cardiac risk

19. PATIENT RELATED CLINICAL PREDICTORS FOR RISK OF PERI-OP CARDIAC COMPLICATIONS- • MAJOR- acute or recent MI, UA, decompensated CCF, significant arrythmias ,severe valvular heart disease. • INTERMEDIATE- mild Angina ,old MI(more thn 1 mnth), insulin dependent diabetes, compensated CCF, pre-op creatinine >2mg% • MINOR- abnormal ECG, cardiac rhythm abnormality, history of stroke, uncontrolled HTN, low functional capacity.

20. Functional Capacity • 1 MET • Take care of self • Eat, dress, use toilet • Walk indoors • Walk 1-2 level blocks • (2-3 mph) • Light housework • 4 METs • 4 METs • Climb flight of stairs • or walkup a hill • Walk level at 4 mph • Run short distance • Heavy work • Moderate recreation Strenuous sports • >10 METs

21. Surgical Risk and Mortality High (>5%) • - Emergent major operations, particularly in elderly • - Aortic and major vascular procedures • - Peripheral vascular procedures • - Prolonged procedures with large fluid shifts +/- blood loss Intermediate (<5%) • - Intraperitoneal / Intrathoracic surgery • - Carotid endarterectomy - Head and neck surgery • - Orthopedic surgery - Prostate surgery Low (<1%) • - Endoscopic procedures - Superficial procedures • - Cataract surgery - Breast surgery

22. Preoperative Non-Invasive Testing If any 2 factors present: • > = 3 Intermediate clinical predictors • Poor functional capacity (< 4 METS) • High surgical risk

23. Assessment of Cardiac Risk • Resting & ambulatory ECG • Exercise stress testing • Echocardiography • Pharmacologic stress testing Dipyridamole/adenosine thallium scintigraphy Dobutamine echocardiography • Coronary angiography

24. ECG- • CAD- in old MI ,inverted t-wave, prominent and deep Q-wave, location • dysrythmias • Conduction defects • Digitalis toxicity-inverted T-waves , downward sloping of ST segment, narrow QRS complexes, atrial fibrillation. • Chamber enlargement like LVH in hypertensive patients. • Electrolyte imbalance • AMBULATORY ECG monitoring-Confirms whether patients' symptoms are coincident with cardiac arrhythmia, e.g.ventricular ectopic beats or atrial fibrillation ( palpitation)

25. RESTING ECHOCARDIOGRAPHY • USES - to detect presence & significance of valvularhrtds , • to detect CHD • LVEF, • chamber enlargement & hypertrophy • RWMA – types & location the assessment of resting LV fxn not routinely recommended for preop screening.

26. Resting LV Function • Echocardiogram Predictive value • LVEF <35% leads to postop CHF • No consistent correlation with postop ischemia Indications • Poorly controlled CHF • Unknown systolic or diastolic function in valvular heart ds, long standing uncontrolled HTN

27. STRESS TESTING OPTIONS:- • Exercise stress alone (usually Bruce protocol) • Exercise / pharmacological stress with nuclear myocardial perfusion imaging (MPI) • Exercise stress echo • Pharmacologic stress echo

28. Stress echocardiography:- • To assess the myocardial function. • Exercise stress echo- • INDICATIONS- prior non diagnostic or if likelihood of false positive ECG stress test, ECG abnormalities making interpretation of ECG stress testing difficult, for prognostic information post MI, to determine success of intervention . • In exercise stress echo-Images are obtained once pt hs achieved 85% of target HR to see wall motion abn during max workload and lastly recovery images with in 90 sec of peak HR.

29. INDICATION FOR PHARM STRESS ECHO:- Unable to exercise because of: • Intermittent claudication • Neurologic deficits • Rheumatologic or orthopedic conditions • Chronic lung disease • Debilitation, old age Simultaneous evaluation of ischemia and myocardial viability   Inability to achieve target heart rate duringexercise because of therapy with High dose beta-blocker or calcium channel blocker • Dobutamine/dipyridamole/adenosine. • Abn at rest signify scar ts. & abn with incr isotropy and chronotropy indicates decrs blood flow.

31. INDICATIONS FOR EXERCISE STRESS TESTING (TMT) :- • Objective confirmation of ischemia • Assessing extent of ischemia • Documenting exercise capacity • Functional assessment of known CAD • Determining risk and prognosis • Determining need for angiography - High risk cut points • Assessing response to treatment

32. C/I for stress testing:- • Acute myocardial infarction (within two days) • Unstable angina pectoris • Uncontrolled arrhythmias causing symptoms of hemodynamic compromise • Symptomatic severe aortic stenosis • Uncontrolled symptomatic heart failure • Active endocarditis or acute myocarditis or pericarditis • Acute aortic dissection • Acute pulmonary or systemic embolism • Acute noncardiac disorders that may affect exercise performance or may be aggravated by exercise

33. EXERCISE STRESS TESTING:- • Treadmill testing / TMT • Bruce protocol -most popular • 8 stages • Incline and speed increment every 3 minutes interval • Target – to achieve 85-100% of maximum age predicted HR • Achieve at least 6 METS for diagnostic accuracy. • Continuous monitoring for symptoms, ECG and blood pressure and heart rate. • Decrease in coronary blood flow to blocked arteries result in ECG changes and response in HR,BP as well. • The accuracy in predicting CAD depends in part on pretest likelihood of CAD in pts with risk factors.(BAYES THEORM) • Prognostic gradient of ischemic response during TMT.

34. ECG pattern indicative of ischemia:-

35. HIGH RISK INDICATORS DURING TMT • Early positive-stage I: Mortality >5%/year • Strongly positive > 2.5 mm ST depression • ST elevation > 1 mm in leads without Q waves • Fall in SBP >10 mm Hg • Early onset ventricular arrhythmia's • Chronotropic incompetence Ex HR <120/min not due to drugs • Prolonged Ischaemic changes in recovery > 2mm lasting > 6 minutes in multiple leads

36. INDICATIONS FOR MYOCARDIAL PERFUSION IMAGING • Suspected false +ve or-ve TMT • Resting ST changes • LBBB,RBBB,LVH, digitalis, pre-excitation or pacemaker • Inability to exercise • Prognosis of known CAD • Detecting post PTCA or CABG ischemia • Assessing myocardial viability • Risk evaluation in non-cardiac surgery patients • Assessment functional significance of documented coronary stenosis

37. NUCLEAR CARDIAC IMAGING useful for assessing coronary perfusion, has greater sensitivity than exercise stress testing, it can assess LV size & fxn.Images taken in 2 phases: 1st imediately aftr cessation of exc , 2nd 4 hours later to detect reversible ischemia. Size of perfusion abn is the most important indicator of significant CAD • Hot spot- tech.99 pyrrophosphate • Taken up by infarcted segment. • Image detected after 12-14 hours. • Cold spot-thallium 201 • Taken up by normal myocardium. • Image detected in 30-60 min. • Repeat imaging can be done after 3-4 hours.

38. Pharmacological stress testing:- • Adenosine – direct vasodilator • Stenosed arteries already max. dilated, so it cnt dilate thm bt increase BF to healthy myocardium. • Causes bronchospasm and dec preload. Dipyridamole is a indirect vasodilator • With coronary stenosis differential dilatation results in differential flow hence differential uptake of isotope • Side effects- same

39. Dobutamine –induces exercise like state incrs HR and contractility increases regional BF to myocardium. Perfusion abn seen in stenosed part.

40. CORONARY ANGIOGRAPHY • INDICATIONS - Done in Pts having positive stress tests suggesting significant myocardium at risk. -To detect or exclude serious CAD i.e. left main or 3 vsds. -chronic stable angina pts who are severely symptomatic despite medical therapy -Pts with ventricular dysfxn -In young patients with VHD to rule out assoc. CAD before cardiac surgery. -who r being considered 4 revascularization -Helps to decide how many bypass grafts should be performed - 4 definitive diagnosis of CAD individuals whose occupations cud place others life in danger( pilots)

41. THANKS