pre-operative cardiovascular evaluation: guidelines and more

Pre-operative Cardiovascular Evaluation:

Guidelines and MoreEric A. Brody MD, FACC

Medical Director, NA Cardiology and Medical ServicesAssociate Professor of Clinical Medicine

University of Arizona Medical Center

Objectives

• Review Algorithm for Pre-op risk assessment for current guidelines

• Define the roles of the cardiac/medical consultant for the non-cardiac surgery patient

• Discuss “clearance”

• Review the 10 commandments of the cardiac/medical consultant

Mechanisms of Perioperative MI

• Unique postoperative conditions lend themselves to AMI– Volume loss/Fluid Shifts– Anemia– Anxiety/Pain – Tachycardia– Temperature fluctuations– Coagulation cascade

MVO2

Shear Stresses

Excess Catechols

Platelet Activation

What Causes Perioperative MI?

Surgery Patient

Volume Shifts

Anemia

Medication withdrawal

Temperature fluctuation

Acidosis

Underlying CAD

Hypertension

Tachycardia

Anxiety/Pain

Hemostasis

Myocardial Infarction

Treatment of Peri-operative MI

Medical Therapy

Beta Blockers

Ca+ Channel. Blockers

ACE inhibitors/ARB

Antithrombotic Therapy

UFH/LMWH

Anti-thrombins

Thrombolysis

Interventional Therapy

PCI/Stent

Antiplatelet Therapy

ASA

GP2b3a

Thienopyridines

Role of the Medical Consultant

• Identify co-morbidities which may complicate surgery

• Airway/anaesthesia issues

• Functional status of the patient

• Clarify pre-op medications

• Peri-procedural cardiac risk

What is “Cleared”?Questions to answer.

• Patients condition is optimized prior to surgery??

• Benefits outweigh risk of surgery??

• OK to proceed??

• Medical Legal considerations removed???

What is “Cleared”?

• My preference- one of 2 options– “Patient is considered ______________

(low, moderate or high) risk for peri-op cardiovascular complications based on current ACC/AHA guidelines”

-” My recommendations for perioperative care include…..”

-”Patient requires additional testing to better clarify perioperative cardiac risk.”

http://www.americanheart.org/

ACC/AHA Perioperative Guidelines Updates: October 2007

• Last revision: 2002

• Significant changes to previous guidelines

• Dramatic change in perioperative evaluation algorithm.

JACC 2007: vol. 50 (17)

2007 Update

Perioperative Guidelines Algorithm

Need for Emergency non-cardiac Surgery?

Step 1

Operating Room

Perioperative Surveillance and

postop. Risk stratification. Risk Factor management

Yes

No

Step 2


Active Cardiac Conditions

Step 2

Evaluate and Treat per

ACC/AHA guidelines

Consider Operating

RoomYes

Active Cardiac Conditions:Patients require evaluation and treatment before non-

cardiac surgery

• Unstable Coronary Syndromes

• Decompensated CHF• Significant Arrhythmias• Severe Valvular Heart

disease

Unstable or Severe Angina (class III or IV) or recent MI >7

days but < one month


cardiac surgery

Significant Arrhythmias

• High grade AV block

• Mobitz II AVB

• Third degree AVB

• Symptomatic Vent. Arrhythmias/Bradycardia

• SVT/Afib with uncontrolled rate (>100/min)



disease


cardiac surgery

Severe Valvular Heart disease

• Severe Aortic Stenosis

• Critical Mitral Stenosis



disease


Active Cardiac Conditions

Step 2

Evaluate and Treat per

ACC/AHA guidelines

Consider Operating

RoomYes

No

Step 3


Low Risk non-cardiac Surgery?

Step 3

Proceed with planned surgery

Yes

• Endoscopic

• Superficial

• Breast

• Most ambulatory surgeries

• Cataracts/ocular

Low Risk Surgeries


Low Risk non-cardiac Surgery?

Step 3


No

Step 4


Good Functional Capacity without symptoms

(>4 mets)

Step 4


Yes

Assessing Functional Capacity

1 Met 4 mets

ADL’s

Eat, Dress or Toilet

Walk Indoors

Walk 1-2 blocks,

level ground

Light House Work


4 mets >10 mets

Climb 1 flight stairs or walk uphill Walk 4

mph

Run a short distance

Heavy Housework

Strenuous Sports

Moderate sports

Another Way to look at This!!

• No Clinical Risk Factors and Low or intermediate risk surgeries with

good functional capacity may proceed directly to the OR.


Good Functional Capacity without symptoms

(>4 mets)

Step 4


Yes

No or Unknown

Step 5

Clinical Risk Factors

• Ischemic Heart Disease

• Compensated or Prior CHF

• DM (insulin requiring)

• Renal Insufficiency (creat. >2.0)

• Cerebrovascular Disease

Step 5

Lee et al. Circulation. 1999;100:1043-1049.)

Revised Cardiac Risk Index

Procedure Type

Perc

ent

AAA Other Vascular Thoracic Abdominal Orthopedic Other


No Clinical Risk Factors

Step 5



1 or 2 Clinical Risk

Factors

Step 5

Intermediate Risk Surgery

Vascular Surgery

Proceed to OR with

HR control or

Consider Non

invasive testing

Class IIa, LOE B

Class IIb, LOE B

Cardiac Risk Stratification: High Risk Procedures

• Reported Cardiac Risk often >5%

– Emergent major operations, particularly in elderly patients

– Aortic and other major vascular

– Peripheral vascular

– Anticipated prolonged procedures with large fluid shifts or blood loss

Cardiac Risk Stratification: Intermediate Risk Procedures

• Reported cardiac risk generally <5%

– Carotid endarterectomy

– Major head and neck, especially for CA

– Intraperitoneal and intrathoracic

– Orthopedic, especially in elderly

– Radical prostatectomy


3 or more Clinical Risk

Factors

Step 5

Intermediate Risk Surgery

Vascular Surgery

Proceed to OR with

HR control or consider

Non invasive testing

Consider Non-

invasive testing

Class IIa, LOE B

TYPE of Surgery

http://www.surgicalriskcalculator.com/miorcardiacarrest

On line tool to calculate patient and procedure specific risk for planned

surgery

ACC/AHA Perioperative Guidelines Updates: October

2007Miscellaneous


• Who Needs an ECG??• Undergoing Vascular surgery (one or more clinical

risk factors) Class I

• Undergoing Vascular Surgery (no risk factors) IIa

• Intermediate risk surgery with established CVD (CAD, PVD, Cerebrovascular disease) Class I

• Intermediate Risk surgery with one or more clinical risk factors


• Who Needs an ECG??– CLASS III- ECG not needed in asymptomatic

patients undergoing low risk surgical procedures.

Recommendations for Statin Therapy


• Class I- (LOE B)

– Patients taking statins should be continued on this therapy at time of non-cardiac surgery

Best Treatment of Perioperative MI

Conclusions: Ways to Avoid Cardiac Complications

• Know the Patient’s History

– Prior MI or known CAD

– Prior CHF and LVEF

– Renal Failure/ baseline Creatinine

– History of significant Valvular heart disease

• Stenosis > regurgitation


• Know what your surgeons and anesthesiologists did– Speak with them directly to coordinate

perioperative care.– Blood loss/serial hematocrits– Fluid resuscitation– Check the post op orders yourself

Challenges for Primary ProvidersACC/AHA Perioperative Guidelines Updates: October 2007

• Our own insecurities– Long history of “clearance” performed

by cardiologists

• Changing the Culture– Surgeons

– Anesthesiologists


• Getting the surgeons to listen to peri-operative recommendations– “You lost me at ‘Cleared’…..”

– Importance of continuing statin therapy and beta blocker therapy in those already taking these medications


• Know the patients’ medications

– Continue Beta Blockers if on these preoperatively

– Prophylactic beta blockade is not indicated in all patients


• The “Business” of stress testing and preoperative evalutation

• Who’s going to pay?

Preoperative Evaluation

Keep it simple!!

pre-operative cardiovascular evaluation: guidelines and more

Documents

perioperative cardiac

emergency noncardiac

risk of surgery

monthactive cardiac

perioperative care

high risk

risk stratification

preop risk assessment