Internal Medicine Board review conference at SIU Medicine for preoperative consultation. Primary resource for this presentation was the most current version of the MKSAP. Risk assessment methods and risk reduction methods discussed.

1. Preoperative
Consultation
Internal Medicine Board Review Conference
Robert Robinson, MD, FACP
Assistant Professor of Clinical Medicine

2. Educational Objectives
Understand reasons for consultation
Understand role of IM consultant
Understand cardiovascular risk assessment
Understand pulmonary risk assessment

3. Educational Objectives
Understand reasons for consultation
Understand role of IM consultant
Understand cardiovascular risk assessment
Understand pulmonary risk assessment

4. “Preop Clearance?”

5. Reasons for Preoperative Consultation
Risk assessment
Risk reduction
Liability reduction?

6. Educational Objectives
Understand reasons for consultation
Understand role of IM consultant
Understand cardiovascular risk assessment
Understand pulmonary risk assessment

7. Role of the IM Consultant
Assess and manage risk
Manage chronic medical problems
Monitor for postoperative complications

8. Other factors to consider…
Customer service
Patient
Surgeon
Local standard of care
Preop testing?
Preop for cataract surgery?
Practice revenue

9. Educational Objectives
Understand reasons for consultation
Understand role of IM consultant
Understand cardiovascular risk assessment
Understand pulmonary risk assessment

10. Cardiovascular Risk Assessment

11. Importance of assessing Cardiovascular Risk
Cardiac Death and Nonfatal MI
Occur in 0.2% all general anesthesia cases and surgery
~500,000 deaths annually
Cardiac death
40% perioperative mortality
Myocardial Infarction (MI)
Most often occurs within 4 days of surgery
15-25% mortality rate
Nonfatal perioperative MI increases 6 month risk
Cardiovascular events
Death
Robert Robinson, MD 11Current Diagnosis & Treatment Cardiology 3rd Edition

12. Cardiac Complications
General anesthesia risks
Myocardial depression
Transient hypotension
Tachycardia
Few deaths occur intraoperatively
Risk of cardiac complications peaks 2-5 days
postoperatively
Pneumonitis and atelectasis produce V/Q mismatch
Sedation or analgesia can produce respiratory depression
Thrombosis is favored due to tissue damage
Sympathetic activation increases myocardial oxygen consumption
Robert Robinson, MD 12

13. Surgery Specific Risks
Low Risk
(<1%)
• Endoscopy
• Superficial Biopsy
• Cataract
• Hysterectomy
• Vasectomy
Moderate Risk
(1-5%)
• Endarterectomy
• Abdominal
• Orthopedic
• Head/Neck
• Nephrectomy
• Prostate
High Risk
(>5%)
• Major vascular
• Prolonged
• Emergency
Robert Robinson, MD 13
ACC/AHA Guidelines, 2007

14. Revised Cardiac Risk Index
Risk Factors
High risk surgery
Ischemic heart disease
History of heart failure
History of cerebrovascular
disease
Diabetes requiring insulin
Preoperative creatinine >2.0
mg/dL
Risk Class
Class I zero risk factors 0.4%
Class II one risk factor 0.9%
Class III two risk factors 6.6%
Class IV three or more risk
factors 11%
Class III or IV risk
Require additional cardiac testing
for risk stratification AND more
aggressive perioperative medical
management
Robert Robinson, MD 14
ACC/AHA Guidelines, 2007

15. Figure 1. Cardiac evaluation and care algorithm for noncardiac surgery
Fleisher L A et al. Circulation 2007;116:e418-e500
Copyright © American Heart Association

16. When to Order Preop Testing
Robert Robinson, MD 16
Risk
Intermediate
or
High
Non Invasive Cardiac
Testing
No Testing if
<5 Years from
Revascularization
or
<2 years from
Non Invasive Testing
Low No Further Testing

17. New directions in cardiovascular risk
assessment

18. Development and Validation of a Risk Calculator for
Prediction of Cardiac Risk After SurgeryClinical
Perspective
by Prateek K. Gupta, Himani Gupta, Abhishek Sundaram, Manu Kaushik, Xiang Fang,
Weldon J. Miller, Dennis J. Esterbrooks, Claire B. Hunter, Iraklis I. Pipinos, Jason M.
Johanning, Thomas G. Lynch, R. Armour Forse, Syed M. Mohiuddin, and Aryan N.
Mooss
Circulation
Volume 124(4):381-387
July 26, 2011
Copyright © American Heart Association

19. Gupta Perioperative Cardiac Risk Calculator
• Free medical calculator
• Smartphones
• Tablets

20. Cardiovascular Risk Reduction
Robert Robinson, MD 20

21. Indications for Revascularization
• Left Main Stenosis
• Triple Vessel Disease
• Severe Ventricular
Dysfunction
Revascularize
• Use of bare metal
stents decreases risk
of coronary
thrombosis
Delay Surgery
At least 6 weeks post
stent
Robert Robinson, MD 21

22. Date of download:
11/16/2012
Copyright © The American College of Cardiology.
All rights reserved.
From: A Clinical Randomized Trial to Evaluate the Safety of a Noninvasive Approach in High-Risk Patients
Undergoing Major Vascular Surgery: The DECREASE-V Pilot Study
J Am Coll Cardiol. 2007;49(17):1763-1769. doi:10.1016/j.jacc.2006.11.052
Incidence of All-Cause Death or Myocardial Infarction During 1-Year Follow-Up According to the Allocated Strategy in Patients With
3 or More Cardiac Risk Factors With Extensive Stress-Induced Ischemia
Light line = best medical treatment only; dark line = best medical treatment and prophylactic revascularization.
Figure Legend:

23. Date of download:
11/16/2012
Copyright © The American College of Cardiology.
All rights reserved.
From: Pre-Operative Risk Assessment and Risk Reduction Before Surgery
J Am Coll Cardiol. 2008;51(20):1913-1924. doi:10.1016/j.jacc.2008.03.005
Prophylactic Coronary Revascularization
Results of the CARP (Coronary Artery Revascularization Prophylaxis) study: long-term survival among patients assigned to
undergo coronary artery revascularization or no revascularization. Reprinted with permission from McFalls et al. (31).
Figure Legend:

24. Anti-platelet Drug
Management

25. Figure 3. Proposed treatment for patients requiring percutaneous coronary intervention (PCI)
who need subsequent surgery.
Fleisher L A et al. Circulation 2007;116:e418-e500
Copyright © American Heart Association

26. Figure 2. Proposed approach to the management of patients with previous percutaneous
coronary intervention (PCI) who require noncardiac surgery, based on expert opinion.
Fleisher L A et al. Circulation 2007;116:e418-e500
Copyright © American Heart Association

27. ….New Data…

28. Date of download: 12/11/2013
Copyright © 2012 American Medical
Association. All rights reserved.
From: Risk of Major Adverse Cardiac Events Following Noncardiac Surgery in Patients With Coronary Stents
JAMA. 2013;310(14):1462-1472. doi:10.1001/jama.2013.278787
Association With Perioperative Antiplatelet Management and 30-Day Postoperative Major Adverse Cardiac Event in Matched Case-
Control Cohort
Figure Legend:

29. ….may change management

30. Reducing Risk with Medications
Beta blockers
Meta analysis of 33 trials showed no clear benefit
Lancet 2008;372(9654):1962-1976
Reduced morbidity and mortality in some trials
Higher risk patient = higher benefit
Metoprolol in patients not on beta blocker therapy
5-10 mg IV every 4-6 hours
Titrate to pulse of 60 bpm
Statins
Intermediate and high risk patients
Clonidine?
Robert Robinson, MD 30

31. Date of download:
11/16/2012
Copyright © The American College of Cardiology.
All rights reserved.
From: Pre-Operative Risk Assessment and Risk Reduction Before Surgery
J Am Coll Cardiol. 2008;51(20):1913-1924. doi:10.1016/j.jacc.2008.03.005
Perioperative Beta-Blocker Therapy
Comparison of patients treated with perioperative beta-blocker therapy versus no drug or placebo.
CI = confidence interval; MI = myocardial infarction; OR = odds ratio; Rx = treatment. Reprinted, with permission, from Schouten et
al. (44).
Figure Legend:

32. Date of download:
11/16/2012
Copyright © The American College of Cardiology.
All rights reserved.
From: Pre-Operative Risk Assessment and Risk Reduction Before Surgery
J Am Coll Cardiol. 2008;51(20):1913-1924. doi:10.1016/j.jacc.2008.03.005
Perioperative Statin Therapy
Results of the effect of perioperative statin therapy in different studies. CI = confidence interval; OR = odds ratio.
Figure Legend:

33. Educational Objectives
Understand reasons for consultation
Understand role of IM consultant
Understand cardiovascular risk assessment
Understand pulmonary risk assessment

34. Pulmonary Risk Assessment
Robert Robinson, MD 34

35. Perioperative Pulmonary Complications
Pneumonia
Mucous plugs
Atelectasis
Respiratory failure
Respiratory depression
V/Q Mismatch
As common as
cardiovascular
complications
Similar impact on
morbidity and
mortality
Robert Robinson, MD 35

36. Surgical Impact on Pulmonary Function
Vital Capacity reduced 1 week post operatively
Functional Residual Capacity reduced by up to 30%
Worsening of OSA (due to medications)
Robert Robinson, MD 36

37. Date of download:
11/16/2012
Copyright © The American College of Physicians.
All rights reserved.
From: Risk Assessment for and Strategies To Reduce Perioperative Pulmonary Complications for Patients
Undergoing Noncardiothoracic Surgery: A Guideline from the American College of Physicians
Ann Intern Med. 2006;144(8):575-580. doi:10.7326/0003-4819-144-8-200604180-00008
American Society of Anesthesiologists Classification
Figure Legend:

38. Risk Factors for Pulmonary Complications
Robert Robinson, MD 38
Cleveland Clinic Journal of Medicine November 2009 vol. 76 Suppl 4 S60-S65

39. Procedure Related Risk Factors
Risk Factor # Studies Pooled Estimate OR
Surgical Site
Aortic 2 6.9
Thoracic 3 4.24
Any abdominal 6 3.09
Neurosurgery 2 2.53
Head and Neck 2 2.21
Emergency 6 2.52
Prolonged surgery 5 2.26
General anesthesia 6 2.35
Transfusion (>4 units) 2 1.47
Robert Robinson, MD 39
Annals Int Med 2006;144:581-595

40. Assessing the Risk of Pulmonary Complications
Careful and Thorough
History and Physical
Exam
COPD or
Asthma
Unsure if at
Baseline
Smoking Hx
High Risk
Surgery
Unexplained
Dyspnea or
Exercise
Intolerance
ASA > 1
Negative
Low Risk
Proceed to
Surgery
CXR or PFT
Consider
surgical
alternatives
Optimize
perioperative
therapy
Robert Robinson, MD 40

41. Screening for Obstructive Sleep Apnea
Robert Robinson, MD 41

42. Date of download: 12/11/2013
Copyright © American College of Chest Physicians. All rights reserved.
From: Development and Validation of a Risk Calculator Predicting Postoperative Respiratory FailureRisk
Calculator Predicting Respiratory Failure
Chest. 2011;140(5):1207-1215. doi:10.1378/chest.11-0466
Calibration of predictions of PRF in the training set (final model). ♦Denotes deciles of patients. See Figure 1 legend for expansion of
abbreviation.
Figure Legend:

43. Gupta Perioperative Pulmonary Risk Calculator
• Free medical calculator
• Smartphones
• Tablets

44. Spirometry
Helps identify patients with COPD
Not superior to clinical evaluation at predicting risk
Obtain for PFTs for
COPD or Asthma if unable to assess if patient is at
baseline
Unexplained dyspnea or exercise intolerance
Robert Robinson, MD 44

45. Pulmonary Risk Reduction
Robert Robinson, MD 45

46. Robert Robinson, MD 46
Cleveland Clinic Journal of Medicine November 2009 vol. 76 Suppl 4 S60-S65

47. Postoperative Delirium
Robert Robinson, MD 47

48. Rates of Postoperative Delirium
35% after major vascular surgery
60% after hip fracture repair
Robert Robinson, MD 48

49. Risk factors for Postop Delirium
Preop Factors
Age
Cognitive impairment
Cerebrovascular disease
Neurodegenerative
disease
History of delirium
ETOH abuse
BZD or Narcotic use
Postop factors
Low HgB
Low O2 Saturation
Abnormal sodium
Abnormal potassium
Abnormal glucose
Poor pain control
Robert Robinson, MD 49

50. Treatment of Delirium
Identify and treat underlying cause
Limit drugs that can cause delirium
Reorient patient
Evaluate for withdrawal
Alcohol
Benzodiazepines
Antipsychotic agents if needed
Robert Robinson, MD 50