Update on Perioperative Medicine Hugo Quinny Cheng, MD Division of Hospital Medicine University of California, San Francisco.

Update on Perioperative Medicine

Hugo Quinny Cheng, MDDivision of Hospital Medicine

University of California, San Francisco

Update on Perioperative Medicine

1. Who needs a preoperative cardiac stress test?

2. What are the benefits and risks of -blockers?

3. Can statins prevent postoperative MI?

4. When can patients with stents go to the OR?

5. How should chronic anticoagulation be managed?

6. Should arthroscopy patients get DVT prophylaxis?

7. Is preoperative smoking cessation beneficial?

Preoperative Stress Testing

A 65 y.o. man with a history of coronary artery disease and long-standing diabetes will undergo radical prostatectomy. He had a myocardial infarction in 2003, but now has no cardiac symptoms.

Meds: lovastatin, atenolol, glyburide, benazepril, ASA

Exam: BP=115 / 70 HR=60; normal heart & lung exam

ECG: NSR, LVH, otherwise normal

65 y.o. man s/f radical prostatectomy. History of remote MI and long-standing diabetes. He is currently asymptomatic.

1. Stress test prior to surgery

2. No stress test is needed

3. Make him carry a copy of Harrison’s up a flight of stairs

“New Standard” Cardiac Risk Index

Predictors:– Higher risk operation*– Ischemic heart disease– Congestive heart failure– Diabetes requiring insulin– Creatinine > 2 mg/dL– Stroke or TIA

Predictors Complications**

0 0.5%

1 1.3%

2 4%

3 or more 9%

* Defined as intraperitoneal, intrathoracic, or suprainguinal vascular surgery

** Defined as MI, pulmonary edema, cardiac arrest, complete heart block

Lee, et al. Circulation, 1999

2007 ACC/AHA Guideline

Good Functional Capacity? Go to OR yes

≥ 3 predictors1 or 2 predictorsno predictors*

no or ?

Control HR & go to OR (IIa)

Vascular surgery?

Consider stress test if results will change management (IIa)

no

yes

or(IIb)

Go to OR

* CAD, CHF, DM, CKD, CVA/TIA

770 vascular patients with 1 or 2 of following:

Age > 70, MI, angina, CHF, DM, stroke / TIA, Cr > 1.8

Stress test (n = 386)No stress test (n = 384)

34 with extensive ischemia (9%); 12 had PCI or CABG

352 with no or limited ischemia

1.8% 30-day CV Death or MI

2.3%

1.1% 15%

Poldermans et al. JACC, 2006

0%

10%

20%

30%

40%

Revascularization +Medical Mgt

MedicalManagement

Dea

th o

r M

I

Poldermans, et al. JACC, 2007

Extensive Ischemia Predicts High Risk

101 patients undergoing vascular surgery, all with ≥ 3 risk predictors and stress test showing extensive ischemia

Reducing Risk with Medical Management

A 75 y.o. woman will undergo hemicolectomy next week. She has a history of diabetes and a remote stroke, but no current cardiovascular symptoms.

1. Start a -blocker

2. Start a statin

3. Start both -blocker & statin

4. No new medications needed

- 111 patients undergoing vascular surgery - All had ischemic potential on dobutamine echo- Randomized to beta-blocker or standard care

Poldermans, et al. NEJM, 1999

40

Cardiac

Mortality &

Nonfatal MI

(%)

7 14 21 28

10

20

30

Days after Surgery

Bisoprolol

Standard Care

POISE: PeriOperative Ischemia Evaluation

8351 patients with s/f major noncardiac surgery• CAD, CHF, CVA/TIA, CKD, DM, or high-risk surgery• Not already taking -blocker

Metoprolol XL (immediately preop until 30 days postop)

Placebo

Patients followed for 30 days after surgery:

1° Endpoint: cardiac mortality & nonfatal arrest or MI

Poise Study Group. Lancet, 2008

POISE: Results

6.9%

2.3%

5.8%

3.1%

0%

1%

2%

3%

4%

5%

6%

7%

8%

CV Death, CardiacArrest, Nonfatal MI

Total Mortality

Placebo

Metoprolol XL

Metoprolol XL:Reduced cardiac events (mostly nonfatal MI)

but

Increased risk of stroke & total mortality

Poise Study Group. Lancet, 2008

POISE: Treatment Protocol

2-4 h

1st dose Metoprolol 100 mg XL*

2nd dose

Metoprolol 100 mg XL*

3rd & daily dose Metoprolol 200 mg XL*^

OR 0-6 h 12 h

* Study drug held for SBP < 100 or HR < 50^ Daily dose reduced to 100 mg if persistent bradycardia or hypotension

DECREASE III

497 statin naive patients s/f vascular surgery

Fluvastatin XL 80 mg/day• Started > 1 month preop• Continued > 1 mo postop

Placebo

Patients followed for 30 days after surgery:

Clinical Endpoint: cardiac death or nonfatal MI

Poldermans et al. Presented at ESC, 2008

DECREASE III: Results

10.1%

4.8%

0%

5%

10%

15%

20%

Cardiac Death or MI

Placebo

Fluvastatin XL

Fluvastatin XL:Reduced the composite outcome of cardiac death & nonfatal MI

No difference in rates of LFT or CPK elevation

Poldermans et al. Presented at ESC, 2008

DECREASE-IV

• 1066 patients with estimated 1-6% risk of postoperatived cardiac complications

• Randomized to: Bisoprolol

Fluvastatin XL

Bisoprolol + Fluvastatin

Double placebo• Drugs started average 34 days prior to surgery

• Primary endpoint: 30-day CV death or nonfatal MI

DECREASE-IV Results

Bisoprolol-treated patients had fewer complications

Trend towards benefit with statins

No safety issues

* *

* P < .002

Dunkelgrun et al. Ann Surg, 2009

Perioperative -blockers in 2009

Strong indications:• Already using -blocker to treat angina, HTN, arrhythmia• Patients with ischemic potential having vascular surgery

Possible indications:• Patients with ischemic potential having high-risk nonvascular

surgery (e.g., > 5 hours or > 500 cc blood loss)• Multiple risk predictors* in vascular or other high-risk surgery

(*Coronary disease, renal insufficiency, diabetes)

Titrate dose up gradually (rarely start immediately preop)

Statins: 2007 ACC/AHA Guideline

Definite indications (class I):• Continue statin if already taking prior to surgery

Probable indications (class IIa):• All vascular surgery patients

Possible indications (class IIb):• At least one risk predictor* in any intermediate risk surgery

*Coronary disease, renal insufficiency, diabetes, CVA/TIA

Delaying Surgery After Coronary Stent

A woman falls and suffers a cervical spine fracture. One month ago, she received a sirulimus-eluting stent for stable angina. The neurosurgeon won’t operate unless aspirin and clopidogrel are held for her surgery. Non-operative management in a halo for next 2 months is offered as an alternative.

What do you recommend to the patient & surgeon?

Patient with recently placed drug-eluting stent has a c-spine fracture. Surgeon won’t operate unless aspirin & clopidogrel are held perioperatively.

1. Hold ASA & clopidogrel

2. Hold ASA & clopidogrel but bridge with heparin

3. Keep her in a halo for next 2 months

Does Heparin Bridge Prevent Stent-related

Complications?

Prospective study of 103 patients with coronary stent placed within 12 months having noncardiac surgery• Antiplatelet drugs continued or held < 3 days• All patients received heparin drip or enoxaparin

14% of patient stented within 35 days of surgery suffered cardiac death or MI, or needed re-do PCI

Conclusion: High rate of cardiac complications even when bridging anticoagulants used

Vicenzi et al. Br J Anaesth, 2006

ACC/AHA Guidelines for PCI

• Avoid PCI unless patient has independent indications• Avoid PCI if patient may have upcoming surgery that

requires stopping dual antiplatelet therapy• Delay elective surgery in patients with recent PCI

– Balloon angioplasty: 2 - 4 weeks– Bare metal stent: 4 weeks– Drug eluting stent: 12 months

• If clopidogrel must be stopped, try to continue ASA• No evidence for bridging with other agents

Managing Perioperative Anticoagulation

Two patients who take coumadin underwent THA. One has atrial fibrillation due to HTN. The other has a mechanical AVR. Neither has a history of stroke or any other comorbidity.

1. Heparin bridge for AVR only

2. Heparin bridge for AF only

3. Heparin bridge for both

4. Heparin bridge for neither

Two patients who take coumadin underwent THA. One has AF due to HTN. The other has a mechanical AVR. Neither has a history of stroke any other comorbidity.

1. Heparin bridge for AVR only

2. Heparin bridge for AF only

3. Heparin bridge for both

4. Heparin bridge for neither

Thromboembolic Risks with Non-rheumatic Atrial Fibrillation

0%

1%

2%

3%

4%

5%

6%

7%

Without Coumadin With Coumadin

Ann

ual S

trok

e R

isk

Albers et al. Chest, 2001

CHADS-2 Score:

1 point for CHF, HTN, Age > 75, DM

2 points for Stroke/TIA

Score 0 - 2: < 5% annual stroke risk Score 3 - 4: 5-10%

Score 5 - 6: > 10%

Thromboembolic Risks with Mechanical Valves

0%

1%

2%

3%

4%

5%

6%

7%

Without Coumadin With Coumadin

Valve Thrombosis

Embolism

Ann

ual I

ncid

ence

Cannegieter, et al. Circulation, 1994

Effect of Mechanical Valve Location & Design on Thromboembolic Risk

Valve Location:

Aortic RR = 1.0

Mitral RR = 1.8

Valve Design:

Caged Ball RR = 1.0

Tilting Disk RR = 0.7

Bi-leaflet RR = 0.6

Cannegieter, et al. Circulation, 1994

Perioperative Anticoagulation: 2008 ACCP Guidelines

Atrial Fibrillation Mechanical Valve Recommend

CHADS2 = 5-6, recent CVA, or rheumatic AF

Any MVR; older (caged-ball or tilting disc) AVR; recent CVA

Full dose heparin bridge

CHADS2 = 3-4 Bileaflet AVR plus one additional stroke risk factor

Full or low dose heparin

CHADS2 = 0-2 Bileaflet AVR without AF or other stroke risk factor

Low dose or no heparin

Full dose = therapeutic dose of heparin IV or LMWH SC

Low dose = DVT prophylaxis dose of heparin SC or LMWH SC

DVT Prophylaxis

Which DVTs matter?• Symptomatic versus asymptomatic • Proximal versus distal

2008 American College of Chest Physicians:• Weights DVT risk greater than bleeding risk• Treats asymptomatic DVT as important

RCT of LMWH in Knee Arthroscopy

Background: 2008 ACCP guidelines recommend LMWH if additional risk factors for DVT are present.

Study Design: ~1300 patients randomized to compression hose or LMWH x 7 days after knee arthroscopy. All patients underwent screening ultrasound.

Results: Combined incidence of death or any clot reduced in patients receiving LMWH (0.9% vs 3.2%). Almost all clots were either asymptomatic or distal. Non-significant trend for increased bleeding.

Conclusions: LMWH superior to compression hose after knee arthroscopy (NNT = 43). Impact on symptomatic DVT small.

Camporese et al. Ann Intern Med, 2008.

Preoperative Smoking Cessation

A middle-aged man will undergo repair of a ventral hernia in 1 month. He currently smokes one pack of cigarettes per day. How do you counsel him?

1. Quit smoking now to prevent postoperative complications.

2. It’s always good to quit, but it’s too late to affect your risk of complications.

3. Don’t stop smoking! You will actually increase your surgical risk by quitting!

Effect of Smoking Cessation

0 10 20 30 40 50 60 70

Nonsmokers

8 or more weeks

4 - 8 weeks

2 - 4 weeks

Less than 2 weeks

Never quit

Complication Rate (%)

Time since quitting

p < .001

Warner, Anesthesiology 1984

Preoperative Smoking Cessation Counseling

RCTs of Preoperative Smoking Cessation Counseling:1. 120 patients undergoing arthroplasty in 6-8 weeks

2. 117 patients undergoing various operations in 4 weeks

3. 60 patients undergoing colorectal resection in 2-3 weeks

Intervention: Smoking cessation counseling at weekly meetings (or by telephone) & offer free nicotine replacement products

Outcomes: Postop complications, especically wound related (e.g., dehiscence, infection, hematoma)

7%

31%

52%

83%

5%

18%

0%

20%

40%

60%

80%

100%

Quit or ReducedSmoking

WoundComplication

Any Complication

Control

Intervention

Smoking Cessation 6-8 Weeks Before TKA or THA

Moller et al. Lancet, 2002

26%

41%

13%

21%

0%

10%

20%

30%

40%

50%

Wound Complication Any Complication

Control

Intervention

Lindstrom et al. Ann Surg, 2008.

Smoking Cessation 4 Weeks Before Surgery

13%

27%

43%

89%

33%41%

0%

20%

40%

60%

80%

100%

Quit or ReducedSmoking

WoundComplication

Any Complication

Control

Intervention

Sorensen, et al. Colorectal Dis, 2003

Smoking Cessation 2-3 Weeks Before Colorectal Surgery

Take Home Points

• Reserve stress testing for higher risk patients

-- Limited ischemia ok, but extensive ischemia = high risk

• Start -blocker cautiously & only in high risk patients

• Delay surgery in patients with recent stent placement

• Individualize thrombotic risk assessment when managing perioperative anticoagulation

• Consider LMWH for knee arthroplasty patients

• Smoking cessation for ≥ 4 weeks may be beneficial