Powerpoint Slides on this Topic

2,732 views

Published on

  • Be the first to comment

Powerpoint Slides on this Topic

  1. 1. Dartmouth-Hitchcock Preoperative Assessment of the Cardiac Patient for Non-cardiac Surgery John R. Butterly, M.D.
  2. 2. Dartmouth-Hitchcock Issues Overview of ischemic heart disease General considerations – Anesthetic – Operative Clinical assessment Predictors of risk – Clinical – Procedural Disease specific states – CAD, hypertension, CHF, valvular Preoperative therapy
  3. 3. Dartmouth-Hitchcock Bottom Line Indications for evaluation/intervention are the same as in the general population Pre-operative evaluation should be seen as an opportunity to provide recommendations for care over the long-term as well as the immediate, peri-operative period Intervention is rarely necessary to lower the risk of non-cardiac surgery
  4. 4. Dartmouth-Hitchcock Overview of Ischemic Heart Disease Anatomy Physiology – coronary – left ventricular – patient
  5. 5. Dartmouth-Hitchcock Etiology of Ischemia Supply – blood O2 carrying capacity – cardiac output – systemic vascular resistance – coronary resistance (Poiseuille) Demand – Major determinants of MVO2 » systolic work heart rate blood pressure (afterload) duration of systole » ventricular wall tension (LaPlace) » contractility » myocardial mass coronary resistance ~ 1/R4 T = PR
  6. 6. Dartmouth-Hitchcock Ischemia vs Infarction Implications of demand related problem vs supply related problem – stability – biology » endothelial function » plaque rupture/thrombosis
  7. 7. Dartmouth-Hitchcock General Considerations A substantial proportion of all deaths in most series of non-cardiac operations arise from cardiovascular complications. Stresses to cardiovascular system – decrease in myocardial contractility & respiration – fluctuations in temperature, afterload, preload, blood volume, & autonomic nervous system output
  8. 8. Dartmouth-Hitchcock General Considerations Possible complications of anesthesia & surgery may impose additional burdens – hemorrhage – infection – pulmonary embolism – myocardial infarction
  9. 9. Dartmouth-Hitchcock Anesthetic Considerations Factors influencing cardiovascular function – direct effect of anesthetic agent on heart – indirect effects mediated through the autonomic nervous system – level of ventilation » hypoxia » hypercarbia » acidosis
  10. 10. Dartmouth-Hitchcock Anesthetic Agents General – inhalation – intravenous – muscle relaxants Spinal/Epidural – hemodynamic consideration The skill & experience of the anesthesiologist, including the ability to monitor hemodynamics & respond quickly, are far more important than the specific agent used.
  11. 11. Dartmouth-Hitchcock Case Study Fragilina Moribundi is a 93 yo, pleasantly demented woman who presents to your office speaking fluent diabinase. She is referred for pre-operative cardiac evaluation prior to her planned cataract surgery. She has a history of a systolic murmur, and is s/p IMI in the distant past. Her history is contributory only in the absence of sx’s suggestive of active ischemia or LV dysfunction Her exam is remarkable for findings c/w severe aortic stenosis Her EKG shows findings c/w OIMI
  12. 12. Dartmouth-Hitchcock Case Study Appropriate actions/evaluation would include – stress testing with imaging to risk stratify and rule out active ischemia
  13. 13. Dartmouth-Hitchcock Case Study Appropriate actions/evaluation would include – stress testing with imaging to risk stratify and rule out active ischemia – echocardiography to evaluate the severity of the aortic stenosis and baseline LV function
  14. 14. Dartmouth-Hitchcock Case Study Appropriate actions/evaluation would include – stress testing with imaging to risk stratify and rule out active ischemia – echocardiography to evaluate the severity of the aortic stenosis and baseline LV function – cardiac catheterization with an eye towards balloon valvuloplasty, if severe aortic stenosis is confirmed, as a bridge to get her through the proposed surgery
  15. 15. Dartmouth-Hitchcock Case Study Appropriate actions/evaluation would include – stress testing with imaging to risk stratify and rule out active ischemia – echocardiography to evaluate the severity of the aortic stenosis and baseline LV function – cardiac catheterization with an eye towards balloon valvuloplasty, if severe aortic stenosis is confirmed, as a bridge to get her through the proposed surgery – a discussion with the PCP re: the indications for the proposed surgery, and clearance for same with appropriate precautions
  16. 16. Dartmouth-Hitchcock Case Study Mrs. Moribundi does well with her cataract extraction, but 2 months later presents to the ER with evidence for total bowel obstruction and free air under the diaphragm. You are emergently consulted by the general surgeons who want to take her to the OR. Appropriate actions include: – emergency echocardiogram to evaluate status of valve and ventricle
  17. 17. Dartmouth-Hitchcock Case Study Mrs. Moribundi does well with her cataract extraction, but 2 months later presents to the ER with evidence for total bowel obstruction and free air under the diaphragm. You are emergently consulted by the general surgeons who want to take her to the OR. Appropriate actions include: – emergency echocardiogram to evaluate status of valve and ventricle – trip to the cath lab for emergency balloon valvuloplasty
  18. 18. Dartmouth-Hitchcock Case Study Mrs. Moribundi does well with her cataract extraction, but 2 months later presents to the ER with evidence for total bowel obstruction and free air under the diaphragm. You are emergently consulted by the general surgeons who want to take her to the OR. Appropriate actions include: – emergency echocardiogram to evaluate status of valve and ventricle – trip to the cath lab for emergency balloon valvuloplasty – trip to the cath lab for IABP placement prior to surgery
  19. 19. Dartmouth-Hitchcock Case Study Mrs. Moribundi does well with her cataract extraction, but 2 months later presents to the ER with evidence for total bowel obstruction and free air under the diaphragm. You are emergently consulted by the general surgeons who want to take her to the OR. Appropriate actions include: – emergency echocardiogram to evaluate status of valve and ventricle – trip to the cath lab for emergency balloon valvuloplasty – trip to the cath lab for IABP placement prior to surgery – discussion with anesthesia re: optimal peri-operative management/hemodynamic monitoring
  20. 20. Dartmouth-Hitchcock The Operation Type – in general, surgical mortality is 25-50% higher in patients with underlying cardiovascular conditions compared to patients with normal cardiac function. – ophthalmologic surgery & TURP almost always safe – highest cardiovascular complication rates seen in vascular surgery » AAA aortic cross-clamping, major fluid & electrolyte shifts » carotid / peripheral surgery co-existing CAD, clinical underestimation of severity
  21. 21. Dartmouth-Hitchcock The Operation Duration – correlation is general and mostly related to type of operation – exceptions » operative time prolonged due to complication » operation > 5 hours
  22. 22. Dartmouth-Hitchcock Cardiac Risk for Noncardiac Surgical Procedures High (reported cardiac risk > 5%) – emergent major operations, esp. in elderly – aortic and other major vascular procedures – peripheral vascular procedures – anticipated prolonged procedure with large fluid shift/blood loss
  23. 23. Dartmouth-Hitchcock Cardiac Risk for Noncardiac Surgical Procedures Intermediate (reported cardiac risk < 5%) – carotid endarterectomy – head and neck – intraperitoneal & intrathoracic – orthopedic – prostate
  24. 24. Dartmouth-Hitchcock Cardiac Risk for Noncardiac Surgical Procedures Low (reported cardiac risk < 1%) – endoscopic procedures – superficial procedure – cataract – breast
  25. 25. Dartmouth-Hitchcock Case Study Mr. A. Jean Jacques is a 58 year old gentleman referred for pre-operative evaluation because of one isolated PVC seen on a pre-op EKG. He is scheduled for nephrectomy for a renal mass the following morning He has no cardiac history of which he is aware. His only risk factor is that of a history of 3 years of smoking in college.
  26. 26. Dartmouth-Hitchcock Case Study He considers himself fit, and is proud of being in good physical condition. He plays full court basketball on Saturdays, and wins. He climbed Mount Washington in October and was pleased that a few of his sons friends could not keep up with him. He denies dyspnea or chest discomfort, and his exam is remarkable in that he looks fit and has a resting pulse of 52 on no medications.
  27. 27. Dartmouth-Hitchcock Case Study Appropriate next steps include – routine stress testing to risk stratify and rule out occult ischemia
  28. 28. Dartmouth-Hitchcock Case Study Appropriate next steps include – routine stress testing to risk stratify and rule out occult ischemia – 24 hour Holter monitor to evaluate burden of ventricular ectopy
  29. 29. Dartmouth-Hitchcock Case Study Appropriate next steps include – routine stress testing to risk stratify and rule out occult ischemia – 24 hour Holter monitor to evaluate burden of ventricular ectopy – echocardiogram to rule out unsuspected LV dysfunction
  30. 30. Dartmouth-Hitchcock Case Study Appropriate next steps include – routine stress testing to risk stratify and rule out occult ischemia – 24 hour Holter monitor to evaluate burden of ventricular ectopy – echocardiogram to rule out unsuspected LV dysfunction – clear for surgery with no recommendations for further cardiac evaluation
  31. 31. Dartmouth-Hitchcock Clinical Assessment History – Single most important part of evaluation to determine level of cardiovascular risk » Identify presence of cardiac condition » Evaluate severity, stability » Identify risk factors, co-morbid conditions » Determination of individual functional capacity Taking a history for angina
  32. 32. Dartmouth-Hitchcock The asymptomatic patient Silent ischemia – “active” silent ischemia » Type I - absence of any sx despite the presence of CAD & provocable ischemia (defective anginal warning system) » Type II - sx’s generally present, but patient also has silent episodes – “passive” silent ischemia » sedentary patient » patient limited for other reasons
  33. 33. Dartmouth-Hitchcock Functional Capacity 1 MET – Can you take care of self? – Eat, dress, use toilet? – Walk indoors in house? – Walk a block or two on level at 2-3 mph? – Do light housework like dusting or dishes? 4 METs 4 METs – Climb a flight of stairs, walk up hill? – Walk on level at 4 mph? – Run a short distance? – Heavy housework – Golf, bowling, dancing, doubles tennis – Swimming, singles tennis football, basketball, skiing >10 METs
  34. 34. Dartmouth-Hitchcock Clinical Assessment Physical examination – general appearance – evidence for CHF – evidence for PVD – heart sounds, murmur
  35. 35. Dartmouth-Hitchcock Clinical Assessment Co-morbid conditions – pulmonary – diabetes mellitus * – renal impairment – hematologic disorders
  36. 36. Dartmouth-Hitchcock Clinical Assessment Ancillary studies – CBC, PT/PTT, blood chemistry (electrolytes, BUN, creatinine) – ECG – CXR ??
  37. 37. Dartmouth-Hitchcock Case Study Alvin Falfa is a 63 yo dairy farmer from the Northeast Kingdom. He was discharged from North Country Hospital 3 weeks ago having sustained an uncomplicated, non-Q MI. He has been slowly increasing his activity and is asx. He was incidently found to have an iron deficiency anemia during his hospitalization, and this was felt to be the cause of his MI. Further w/u revealed a large, fungating mass in his cecum, biopsy positive for adenoCa. He is referred for pre-op evaluation prior to his right hemicolectomy which is scheduled for tomorrow morning.
  38. 38. Dartmouth-Hitchcock Case Study Initial appropriate actions include: – postponement of the scheduled surgery
  39. 39. Dartmouth-Hitchcock Case Study Initial appropriate actions include: – postponement of the scheduled surgery – stress testing for risk stratification and to determine whether or not there is inducible ischemia
  40. 40. Dartmouth-Hitchcock Case Study Initial appropriate actions include: – postponement of the scheduled surgery – stress testing for risk stratification and to determine whether or not there is inducible ischemia – echocardiography to evaluate LV function
  41. 41. Dartmouth-Hitchcock Case Study Initial appropriate actions include: – postponement of the scheduled surgery – stress testing for risk stratification and to determine whether or not there is inducible ischemia – echocardiography to evaluate LV function – cardiac catheterization with an eye towards intervention prior to abdominal surgery
  42. 42. Dartmouth-Hitchcock Case Study Initial appropriate actions include: – postponement of the scheduled surgery – stress testing for risk stratification and to determine whether or not there is inducible ischemia – echocardiography to evaluate LV function – cardiac catheterization with an eye towards intervention prior to abdominal surgery – clearance for surgery after a discussion with anesthesia about appropriate peri-operative management/hemodynamic monitoring
  43. 43. Dartmouth-Hitchcock Clinical Predictors of Risk Major – Unstable coronary syndromes » recent MI with evidence for ischemia » unstable or severe angina (Canadian class III or IV) – Decompensated CHF – Significant arrhythmia » high grade AV block » symptomatic ventricular arrhythmia (with organic disease) » supraventricular arrhythmia with uncontrolled rate – Severe valvular disease
  44. 44. Dartmouth-Hitchcock Clinical Predictors of Risk Intermediate – Mild angina pectoris (Canadian class I or II) – Prior MI by history or pathological Q waves – Compensated or prior CHF – Diabetes mellitus – Renal insufficiency (creatinine > 2)
  45. 45. Dartmouth-Hitchcock Clinical Predictors of Risk Minor – Advanced age – abnormal ECG (LVH, LBBB, ST-T change) – Rhythm other than sinus – Low functional capacity – History of stroke – Uncontrolled systemic hypertension
  46. 46. Dartmouth-Hitchcock Determination of need for further cardiac testing Urgency of surgery Recent revascularization Recent coronary evaluation Major predictor of risk Intermediate predictor of risk – functional capacity – risk level of surgery Minor or no predictor of risk – functional capacity – risk level of surgery
  47. 47. Dartmouth-Hitchcock Disease-Specific Approaches Coronary Artery Disease Hypertension Congestive Heart Failure/Cardiomyopathy Valvular Heart Disease Arrhythmias & Conduction Defects Pulmonary Vascular Disease
  48. 48. Dartmouth-Hitchcock Case Study Hiram Wrisck is a 72 yo gentleman referred for evaluation prior to AAA. He describes himself as active, but his wife rolls her eyes behind his back when he says this. He has a positive history of hypertension and adult onset diabetes that recently became insulin dependent, but no history to suggest angina. A stress test done prior to his visit with you demonstrated 1.5mm ST depression in leads II, V4-6 at 4 METS (100 bpm)
  49. 49. Dartmouth-Hitchcock Case Study Physical exam shows him to be an obese 72 year old man looking older than his stated age. He weighs 285#, pulse is 96 with frequent extra-systoles, BP 140/90 in right arm, 190/105 in left arm. The rest of the exam is remarkable for a II/VI SEM at the LSB, bilateral carotid and femoral bruits, and absent pedal pulses.
  50. 50. Dartmouth-Hitchcock Case Study Appropriate next steps include – Repeat stress as a DSE to try to get a heart rate response closer to 85% PMHR
  51. 51. Dartmouth-Hitchcock Case Study Appropriate next steps include – Repeat stress as a DSE to try to get a heart rate response closer to 85% PMHR – Cardiac catheterization with a low threshold for percutaneous or surgical revascularization if anatomically appropriate
  52. 52. Dartmouth-Hitchcock Case Study Appropriate next steps include – Repeat stress as a DSE to try to get a heart rate response closer to 85% PMHR – Cardiac catheterization with a low threshold for percutaneous or surgical revascularization if anatomically appropriate – Recommend intra-operative SG line and i.v. TNG
  53. 53. Dartmouth-Hitchcock Case Study Appropriate next steps include – Repeat stress as a DSE to try to get a heart rate response closer to 85% PMHR – Cardiac catheterization with a low threshold for percutaneous or surgical revascularization if anatomically appropriate – Recommend intra-operative SG line and i.v. TNG – Fully review the medical record in hopes that Andy Torkelson has previously seen him at some point in time
  54. 54. Dartmouth-Hitchcock Coronary Artery Disease Clinically apparent vs occult disease – past history – active symptoms – “active” vs “passive” silent ischemia Issues to be addressed – ischemic threshold – amount of myocardium in jeopardy – left ventricular function
  55. 55. Dartmouth-Hitchcock Coronary Artery Disease Risk assessment based on stress testing High risk – ischemia induced at low level (< 4 METs, heart rate < 100 or < 70% age predicted) with: » ST depression > 0.1 mV » ST elevation > 0.1 mV in noninfarct lead » five or more abnormal leads » persistent ischemic response > 3 minutes post exercise » typical angina – thallium
  56. 56. Dartmouth-Hitchcock Coronary Artery Disease Risk assessment based on stress testing Intermediate risk – ischemia induced at moderate level (4-6 METs, heart rate 100-130 or 70-85% age predicted with: » ST depression > 0.1 mV » typical angina » persistent ischemic response >1-3 minutes post exercise » three to four abnormal leads
  57. 57. Dartmouth-Hitchcock Coronary Artery Disease Risk assessment based on stress testing Low risk – no ischemia or ischemia at high level (> 7 METs, heart rate > 130 or >85% age predicted with: » ST depression > 0.1 mV » typical angina » one to two abnormal leads
  58. 58. Dartmouth-Hitchcock Coronary Artery Disease Indications for Coronary Angiography Class I: patients with suspected or proven CAD » high risk results from noninvasive testing » angina pectoris refractory to medical therapy » unstable angina » nondiagnostic/equivocal test results in high risk pt. Class II: » intermediate risk results from noninvasive testing » nondiagnostic/equivocal test results in intermediate risk pt. » urgent non-cardiac surgery in convalescent period post-MI » perioperative MI
  59. 59. Dartmouth-Hitchcock Coronary Artery Disease Indications for Coronary Angiography Class III: » low risk surgery in pt. with known CAD & low risk testing » screening for CAD » asx pt. after revascularization with exercise capacity > 7 METs » mild, stable angina with good LV function, low risk testing » patient not candidate for revascularization
  60. 60. Dartmouth-Hitchcock Other disease states Hypertension – not independent risk factor – implications for intraoperative lability – rational for preoperative control Congestive heart failure/Cardiomyopathy – confers risk independently – etiology key to risk assessment/treatment
  61. 61. Dartmouth-Hitchcock Other disease states Congestive Heart Failure/Cardiomyopathy » systolic vs diastolic dysfunction » hypertrophic cardiomyopathy Valvular heart disease » aortic stenosis » mitral stenosis » regurgitant (volume overload) lesions » antibiotic prophylaxis / anticoagulation
  62. 62. Dartmouth-Hitchcock Other disease states Arrhythmias & conduction defects » important as markers for underlying disease » therapy aimed to correct or avoid ischemia or hemodynamic embarrassment » high grade AV block - to pace or not to pace Pulmonary vascular disease » little objective data available » sensitivity to hypoxia » implication in presence of pre-existing shunts
  63. 63. Dartmouth-Hitchcock Supplemental Preoperative Evaluation Resting left ventricular function » methodology » when is it good to be over 40? » indications for testing Stress testing » exercise » nonexercise persantine thallium dobutamine stress echocardiography
  64. 64. Dartmouth-Hitchcock Preoperative Therapy Surgical revascularization CASS registry Foster et al Ann Thorac Surg 1986;41:42-50 » 1600 pts. underwent noncardiac operations, 113 (7%) vascular » mortality rates 0.5% without angiographic evidence advanced CAD 0.9% with prior CABG 2.4% with significant CAD (70% stenosis) but no prior revascularization European Coronary Surgery Study Group Lancet 1982;2:1173-80 » survival rates, 58 pts. with PVD randomized to CABG or medical Rx 85% with CABG 57% with medical Rx p=.009 p=.02 p=ns
  65. 65. Dartmouth-Hitchcock Preoperative Therapy Surgical revascularization Cleveland Clinic series Ann Surg. 1984;199:223-233 » 1001 pts. scheduled for elective vascular surgery » mortality rates 5.3% + 1.5% for CABG group (6.8%) 1.4% in group with normal coronaries 1.8% in group with mild to moderate CAD 3.6% in group with advanced, compensated CAD 14% in group with severe, uncorrected CAD » 5 year survival 72% in pts. who underwent CABG 43% in pts. in whom CABG indicated but not performed p=.001
  66. 66. Dartmouth-Hitchcock Preoperative Therapy Surgical revascularization Indications for preoperative CABG – left main stenosis with acceptable risk – 3VD with LV dysfunction – 2VD with severe, proximal LAD disease – coronary ischemia refractory to medical management ACC/AHA Task Force JACC 1991;17:543-589
  67. 67. Dartmouth-Hitchcock Preoperative Therapy Catheter based revascularization Mayo Clinic series Mayo Clin Proc. 1992;67:15-21 » 50 pt. series, high risk group 10% required urgent CABG perioperative MI rate 5.6% mortality rate 1.9% Timing » restenosis » recoil/thrombosis New technologies
  68. 68. Dartmouth-Hitchcock Preoperative Therapy Medical therapy Author Procedure n Control Drug Ischemia control/drug MI control/drug Coriat Anesth 1984 carotid 45 TNG 0.5 mcg/kg/m TNG 1.0 mcg/kg/m 64%/17% 0/0 Dodds Anesth Analg 1993 noncardiac 45 placebo TNG 0.9 mcg/kg/m 32%/30% 4%/0% Godet Anesth 1987 vascular 30 placebo diltiazem 3mcg/kg/m 73%/4% 0/0 Pasternak Circ 1987 AAA 83 case- control metoprolol 50 mg p.o. _____ 18%/3% Pasternak Am J Surg 1989 vascular 200 unblinded metoprolol 50 mg p.o. 2.4/5 episodes _____ Stone Anesth 1988 noncardiac 128 placebo p.o. beta blocker 28%/2% 0/0
  69. 69. Dartmouth-Hitchcock Preoperative Therapy Valve surgery » general considerations » balloon valvuloplasty » stenotic vs regurgitant lesions Arrhythmia/Conduction Devices » ICD’s » pacemakers
  70. 70. Dartmouth-Hitchcock Tools Vs Toys Pulmonary artery catheters Transesophageal echocardiography Intra-aortic balloon counterpulsation
  71. 71. Dartmouth-Hitchcock Summary Overview of ischemic heart disease General considerations – Anesthetic – Operative Clinical assessment Predictors of risk – Clinical – Procedural Disease specific states – CAD, hypertension, CHF, valvular Preoperative therapy
  72. 72. Dartmouth-Hitchcock Conclusions Judgement/Experience/Skill Medical care: a point in time vs continuum Teamwork
  73. 73. Dartmouth-Hitchcock

×