Perioperative Medical Management

1. Perioperative Medical Management Mark C. Wilson, M.D., M.P.H.

4. You Should Expect Questions About ... • Characteristics of Effective Consultations • Appropriate “Routine” Preoperative Testing • Cardiopulmonary Risk Assessment • Perioperative Care of the Elderly • Prevention of Venous Thromboembolism

5. Role of the Medical Consultant is ... “to identify the problems, correct the correctable, and then point out the uncorrectable to the unsuspecting.” G. E. McElwain

6. “Routine” Preoperative Testing Appropriate testing for an asymptomatic 43y/o woman who takes HCTZ and is scheduled for elective hysterectomy: a) Chest X-ray b) Hematocrit c) PT & PTT d) Electrolytes, BUN, Cr e) Electrocardiogram

7. Preoperatively, Don’t Do This ...

8. Or You Could End Up Like This ...

9. Preoperative Testing Driven By: A. The History & Physical Exam - Age - Sex - Medications - Chronic Diseases / Functional Impact - Exercise Tolerance - Nutritional Status B. The Type of Surgery

10. “Routine” Preoperative Testing 1) BEWARE!!! 2) Routine Testing of Unselected, Asymptomatic Adults Does NOT Improve Outcomes 3) Most Important Step is Thorough H&P 4) Evidence Supports that Prior Normal Testing Rarely Evolves into Significant Abnormality

11. Value of Previous Tests • 1,100 patients had 7,500 preoperative tests in VA • 47% were duplicated tests performed within 1 year • 70% of duplicates were performed in prior 4 months • 0.4% of previously normal tests evolved into an abnormality that could alter perioperative care • Most importantly, the rare abnormal values were predictable from clinical assessment of patient Macpherson, Ann Int Med 1990

12. Test Hgb/Hct Lytes, BUN, Cr Coags, Platelets Electrocardiogram Chest X-Ray Setting All Women; Men >60yrs Renal Disease; Diuretics; DM; HTN; Age >60yrs Liver Disease; Coumadin; Easy Bruising; Malignancy History CAD; Age >50yrs Acute Pulm Sx; Age >60yr Reasonable Situations to CONSIDER

13. “Routine” Preoperative Testing Appropriate testing for an asymptomatic 43y/o woman who takes HCTZ and is scheduled for elective hysterectomy: a) Chest X-ray b) Hematocrit c) PT & PTT d) Electrolytes, BUN, Cr e) Electrocardiogram

14. So, Be Discerning with Interventions

16. Cardiopulmonary Case • 67 y/o male referred to you for “pre-op clearance” before elective repair of a large inguinal hernia. • Active farmer with h/o HTN, BPH, and angina since his inferior MI 2yrs ago. Smokes 1 ppd. • Meds: Metoprolol, ASA, Terazosin, NTG What Further Do You Need to Ask???

17. Cardiopulmonary Risk Assessment • Goal is to Assess Whether EXCESS Risk Exists • History and Physical Examination are KEY • Any Recent Change in Chronic Disease Status? • Assess Exercise Tolerance • Does Patient Have a Low, Moderate, or High Cardiac Risk Profile? • What is the Risk Associated with the Surgery?

18. Cardiopulmonary Case • Works “sun-up to sun-down”. Reports good compliance with meds. Occasional SSCP when he “overdoes it” like when uses the rototiller longer than 30 minutes at a time. Prompt pain relief when stops to rest. Last used NTG 1 month ago. • Can walk 1/2 mile without DOE. No PND, orthopnea, or palpitations. • Small amount of tan sputum each morning.

19. Cardiopulmonary Case Physical Exam 148/95 HR - 70 R - 12 Gen: vigorous male with yellow fingernails Lungs: clear with coarse BS bilaterally Heart: regular without murmur or gallop Abd: benign without bruit Ext: no edema, pulses intact bilateral femoral bruits

20. Cardiopulmonary Risk Assessment The most appropriate preoperative testing strategy for this active farmer is: a) Electrocardiogram b) Exercise Treadmill Testing c) Dobutamine Echocardiogram d) Pulmonary Function Testing

21. Cardiac Risk Assessment Consistently Important Predictive Variables: • “Recent” MI • Unstable Angina • Congestive Heart Failure • Aortic Stenosis • Advanced Arrhythmias • Emergency Surgery • Aged

22. 1996 ACC/AHA Guidelines • “… intervention is rarely necessary to lower the risk of surgery.” • “In general, indications for further cardiac testing and treatments are the same as those in the nonoperative setting.”

23. Guideline Comparison

24. Hemodynamic Stress of Surgery • High Risk (cardiac risk > 5%) • Emergency operations • Aortic or other major vascular surgeries • Intermediate Risk (cardiac risk < 5%) • Abdominal surgery • Orthopedic surgery • Head & Neck surgery • Low Risk (cardiac risk < 1%) • Breast surgery • Cataract surgery • Herniorrhaphy ACC/AHA Guideline 1996

25. Pulmonary Risk Assessment • For Patients with Chronic Lung Diseases, Morbid Obesity, or Current Respiratory Infections • Assess Tobacco Use • Assess if Change in Dyspnea, Cough, Sputum • Operative Site is Most Important Determinant • Evidence Supports PFTs Only in Lung Resection • PFTs May be Helpful by Increasing Vigilance • pCO2 > 45 Associated with Adverse Outcomes

26. Cardiopulmonary Risk Assessment The most appropriate preoperative testing strategy for this active farmer is: a) Electrocardiogram b) Exercise Treadmill Testing c) Dobutamine Echocardiogram d) Pulmonary Function Testing

28. Perioperative Care of the Elderly • Status & Functional Impact of Chronic Diseases • Exercise Tolerance • Consider Preoperative MMSE • Polypharmacy and Drug Metabolism Be Wary of Pre-op Medication Changes

29. Postoperative Delerium It Is Common and Often Multifactorial. Consider: • “Sun-Downing” • Infection • Alcohol Withdrawal / New Medications • Abnormal Electrolytes • Hypoxemia • Cardiac Ischemia • Stroke

31. Prevention of DVT 57 y/o obese woman scheduled for resection of ovarian cancer. Prior DVT and h/o CHF. Most appropriate prophylaxis would be: a) Intermittent Pneumatic Compression Devices b) Warfarin and Low Molecular Weight Heparin c) Inferior Vena Cava Filter and Aspirin d) Low Molecular Weight Heparin and IPCDs

32. Once Again, Look for Risk Factors

33. Clinical Risk Factors for DVT • Prior History of DVT or PE • Congestive Heart Failure • Prolonged Immobilization • Malignancy

34. Risk Stratification by ACCP Consensus • Low Risk Patients • Typically <40yrs without risk factors; minor surgeries • Early ambulation • Moderate Risk Patients • Typically >40yrs without risk factors; major surgeries • Low dose heparin q12hrs or IPCD • High Risk Patients • Typically >40yrs with risk factors; major surgeries • Low dose heparin q8hrs or LMWH Chest 1995; 108:312S-334S

35. Hip Fracture or Replacement Total Knee Replacement Neurosurgery Patients Very High Risk Trauma / Recent DVT - LMWH or Warfarin - LMWH or IPCD - IPCD - Combination Strategies - IVC Filter Appropriate DVT Prophylaxis

36. Prevention of DVT 57 y/o obese woman scheduled for resection of ovarian cancer. Prior DVT and h/o CHF. Most appropriate prophylaxis would be: a) Intermittent Pneumatic Compression Devices b) Warfarin and Low Molecular Weight Heparin c) Inferior Vena Cava Filter and Aspirin d) Low Molecular Weight Heparin and IPCDs

38. Fun Consultative Pearls • CV risk equal for general and spinal anesthesia • Beware spinal anesthesia if fixed cardiac output • Many postoperative MIs silent ... and subtle • ASA irreversibly inhibits plts; NSAIDs transiently • Continue cardiac/anti-HTN meds on AM of surgery • Diastolic BP < 110 is not associated with increased perioperative M&M

39. So What Now???

40. Session Objectives 1) Determine Components of Effective Consultation 2) Identify Appropriate Perioperative Testing 3) Review Cardiopulmonary Risk Assessment 4) Identify Unique Aspects of Consultation in Elderly 5) Determine Appropriate DVT Prophylaxis