Transcript Preoperative Cardiac Evaluation & Inspirations in Medicine

Preoperative Cardiac
Evaluation
Jonathan Hastie
January 31, 2006
Preoperative Cardiac Evaluation
I.
II.
III.
IV.
V.
Significance of the preoperative cardiac
evaluation
Risk assessment
Therapeutic interventions
Perioperative surveillance
Summary
Questions
Preoperative Cardiac Evaluation
I.
II.
III.
IV.
V.
Significance of the preoperative cardiac
evaluation
Risk assessment
Therapeutic interventions
Perioperative surveillance
Summary
Questions
Case vignette
• Mr Y is a 77 year old white male with a history
of hypertension, coronary artery disease, and
hypercholesterolemia.
• He presents to the emergency department with
a three week history of worsening dyspnea and
generalized weakness.
• In the E.D., he was found to have a large, rightsided pleural effusion
Case vignette, cont.
• Pus was aspirated on thoracentesis.
Cardiothoracic surgery was consulted, and the
patient was scheduled the following day for a
thoracotomy and decortication.
• Immediately post-op, the patient arrived in
the I.C.U. where he was noted to have STsegment elevations.
Case vignette, cont.
• He was taken emergently for coronary angiography
where two stents were placed.
Case vignette, cont.
• On returning from the cath lab, the patient had a v.
fibrillation arrest and was resuscitated.
• The remainder of his hospital stay was complicated
by cardiogenic shock which gradually improved. He
had a G.I. work-up since the empyema grew G.I. tract
flora.
• After his colonoscopy, the patient had a significant
lower G.I. bleed. He was still on aspirin and Plavix for
his coronary stents.
Surgery in the United States
• 25 million patients undergo noncardiac
surgery yearly
– 50,000 suffer perioperative myocardial
infarction
– >50% of 40,000 perioperative deaths are due
to cardiac events
Surgery in the United States
The Ether-dome
Massachusetts General Hospital
Boston, MA
Cardiovascular disease in the
United States
• 71,000,000 American adults with some
form of cardiovasular disease
– Hypertension: 65,000,000
– Coronary artery disease: 13,200,000
– Heart failure: 5,000,000
– Stroke: 5,500,000
Source: americanheart.org, website of the American Heart Association
Cardiovascular disease in the
United States
• Mortality
– CVD accounts for 37% of all deaths in the US
– Since 1900, CVD has been the number one
killer in the U.S. every year save one.
– 2,500 Americans die from CVD daily.
– Perioperative cardiac morbidity primarily
related to ischemia, heart failure, or
arrhythmias.
Cardiovascular disease in the
United States
• Overheard on my cardiology
elective:
“The heart is simple. In
fact, the A.S.C.A.S. II
trial recently showed that
there are really only
three kinds of problems:
ischemia, congestive
heart failure, and
arrythmias.”
Cardiac risks of
noncardiac surgery
1. Some types identify patients at higher risk for
concomitant cardiac disease.
-Vascular surgery
2. Cardiac stress inherent to surgery
-Fluctuations in heart rate, blood pressure,
intravascular volume, oxygenation
-Anesthetic technique
-Pain
-Emergent procedures
The role of the consultant
• Evaluate the patient’s current medical status
• Provide clinical risk profile
• Recommend management of cardiac risk over
•
the entire perioperative period
Treat modifiable risk factors
Guidelines for Perioperative Cardiovascular Evaluation for Noncardiac Surgery
ACC/AHA 2002
The role of the consultant
• Surgery and medicine
– “I think of surgery as a
pill that I might
prescribe.
Hypertension?
Prescribe a betablocker. Cholecystitis?
Prescribe surgery.”
– M.A., UTSW medicine
resident
The role of the consultant
• Surgery and medicine
– “I think general
surgeons are the best
doctors in the hospital.
I mean, they do
everything that
internists do, and they
operate.”
– R.L. UTSW surgery
resident
Guidelines for Perioperative
Cardiovascular Evaluation for
Noncardiac Surgery
• Developed by the American College of
•
•
•
Cardiology and the American Heart Association
Revised in 2002
Largely based on observational or retrospective
studies
Few randomized prospective studies
Preoperative Cardiac Evaluation
I.
II.
III.
IV.
V.
Significance of the preoperative cardiac
evaluation
Risk assessment
Therapeutic interventions
Perioperative surveillance
Summary
Questions
Risk Assessment
Preoperative Cardiac Evaluation
I.
Significance of the preoperative cardiac evaluation
II. Risk assessment
-Fundamental clinical evaluation
-Clinical predictors of increased risk
-Surgery-specific risks
-Preoperative evaluation algorithm
-Preoperative testing
III.
IV.
V.
Therapeutic interventions
Perioperative surveillance
Summary
Assessing the situation
• Determine the urgency for surgery
• Options to consider (as a team)
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Forgo surgery
Modify the surgical procedure
Delay case (for further testing or patient optimization)
Perioperative medical therapy
Perioperative monitoring
Modification of the location of care
Fundamental clinical evaluation
• History
– Angina
– History of myocardial infarction
– Heart failure symptoms
– Symptomatic arrhythmias
– Pacemaker or ICD
– Comorbid diseases
Fundamental clinical evaluation
• Functional status
1-4 METs
Activities of Daily Living
Walk on level ground
Light housework
4-10 METs
Climb stairs
Heavy housework
Recreational activities
Strenuous sports
Fundamental clinical evaluation
1-4 METs
Activities of Daily Living
Walk on level ground
Light housework
4-10 METs
Climb stairs
Heavy housework
Recreational activities
Strenuous sports
15 METs
Intern on single intern team
Fundamental clinical evaluation
• Physical examination
– Uncontrolled hypertension
– General appearance
– Signs of CHF and valvular disease
– Presence of ICD/pacemaker
Fundamental clinical evaluation
• Electrocardiogram
– Class I: recent chest pain in a moderate-risk
patient undergoing moderate-risk procedure
– Class IIa: Asymptomatic person with diabetes
– Class IIb
• Prior CABG or PTCA
• Asymptomatic male >45 or female >55 with at
least two risk factors
• Prior admit for cardiac causes
– Class III: Routine test for asymptomatic
patients with low-risk procedures
Consult etiquette
• Overheard on my ICU month:
“Did they really just
consult pulmonary
without getting a chest
x-ray?!?”
Assessing the patient
• Minor predictors
– Advanced age
– Abnormal ECG
– Rhythm other than sinus
– Low functional capacity
– Uncontrolled hypertension
Assessing the patient
• Intermediate predictors
– Mild angina pectoris (class 1 or 2)
– Prior MI
– Compensated or prior heart failure
– Diabetes mellitus
– Renal insufficiency
Assessing the patient
• Major predictors
– Acute or recent MI
– Unstable or severe angina
– Decompensated heart failure
– High-grade A-V block
– Severe valvular disease
– Arrhythmias
Surgery-specific risks
• Two factors
– Type of surgery
– Degree of hemodynamic stress
Surgery-specific risks
• Low risk surgeries (<1% cardiac risk)
– Endoscopic procedures
– Superficial biopsies
– Cataracts
– Breast surgery
Surgery-specific risks
• Intermediate risk (<5% cardiac risk)
– Intraperitoneal and intrathoracic
– Carotid endarterectomy
– Head and neck
– Orthopedic
– Prostate
Surgery-specific risks
• High risk (>5% cardiac risk)
– Emergency major operations
• Especially in the elderly
– Aortic or major vascular surgery
– Extensive operations with large volume shifts
or blood loss.
Preoperative evaluation algorithm
“The Road Not Taken” by Robert Frost
Preoperative evaluation algorithm
• Emergent surgery  to O.R.
• Coronary revascularization within five
years, no symptoms  to O.R.
• Recurrent symptoms after
revascularization*, or no cardiac work-up,
then evaluate
– Clinical predictors
– Functional status
– Surgical risks
Preoperative evaluation algorithm
• For patients with major clinical predictors
undergoing non-emergent noncardiac
surgery, consider delaying the surgery.
– Medical management
– Risk factor modification
– Consider coronary angiography
Preoperative evaluation algorithm
• Major predictors
– Acute or recent MI
– Unstable or severe
angina
– Decompensated heart
failure
– High-grade A-V block
– Severe valvular
disease
– Arrhythmias
Preoperative evaluation algorithm
• For patients with intermediate clinical
predictors, evaluate functional status.
• Low functional status (<4 METs) may
merit further testing.
• Moderate to good functional status (>4
mets) promps us to look at the procedure
itself.
Preoperative evaluation algorithm
• Intermediate
predictors
– Mild angina pectoris
(class 1 or 2)
– Prior MI
– Compensated or prior
heart failure
– Diabetes mellitus
– Renal insufficiency
Preoperative evaluation algorithm
• For patients with minor clinical predictors,
evaluate functional status.
• Moderate to good functional status
indicates lowest cardiac risk for all
procedures.
• Poor functional status should prompt us to
evaluate the surgical procedure.
– High risk procedures may merit further
testing.
Preoperative evaluation algorithm
• Minor predictors
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Advanced age
Abnormal ECG
Rhythm other than sinus
Low functional capacity
Uncontrolled hypertension
Preoperative evaluation algorithm
• Consider noninvasive testing if two or
more are present:
– Intermediate clinical predictors
– Poor functional capacity
– High surgical risk procedure
Preoperative testing
• Resting echocardiogram
• Stress testing
– Exercise stress test
– Chemical stress test
• Coronary angiography
Resting echocardiogram
• Has not been found to be a predictor of
perioperative ischemic events
• Recommended in patients with current or
poorly controlled heart failure
• Not recommended as a routine test of left
ventricular function in patients without
prior heart failure.
Stress testing
• Most useful in patients who have
intermediate clinical predictors and poor
functional capacity.
• Useful in patients at risk for CAD
• Prove myocardial ischemia before
revascularization
Preoperative Cardiac Evaluation
I.
II.
III.
IV.
V.
Significance of the preoperative cardiac
evaluation
Risk assessment
Therapeutic interventions
Perioperative surveillance
Summary
Questions
Coronary angiography
• Pre-op indications are similar to “regular”
indications
– High risk of adverse outcome based on
noninvasive tests
Bypass Grafting
• Indications for CABG before noncardiac
surgery are identical to standard
indications for CABG
– Left main disease
– Three vessel disease
Perioperative Medical Therapy
• Paucity of data
• Two randomized, placebo-controlled trials
of perioperative beta blockers
– Reduced perioperative cardiac events
– Improved 6-month survival
• Beta-bocker indications
– High cardiac risk patients undergoing vascular
surgery
– Prior usage for controling angina,
symptomatic arrhythmias, or hypertension
Preoperative Cardiac Evaluation
I.
II.
III.
IV.
V.
Significance of the preoperative cardiac
evaluation
Risk assessment
Therapeutic interventions
Perioperative surveillance
Summary
Questions
Perioperative surveillance
• Poorly studied
• Consider…
– Pulmonary Artery Catheters
– Intraoperative and post-op STmonitoring
– Surveillance for Perioperative MI
• Repeat EKG’s
• Cardiac enzymes
Preoperative Cardiac Evaluation
I.
II.
III.
IV.
V.
Significance of the preoperative cardiac
evaluation
Risk assessment
Therapeutic interventions
Perioperative surveillance
Summary
Questions
Summary
1. Urgency for surgery?
2. Recent coronary revascularization
3.
4.
5.
6.
without symptoms?
Recent coronary evaluation?
Major clinical predictors?
Intermediate clinical predictors?
Poor functional capacity & high-risk
surgery?
Critique
• Should severe valvular stenosis be a major clinical
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•
•
•
predictor?
Do the ACC/AHA guidelines send too many people to
testing?
Does a single intermediate predictor carry as much
weight as multiple intermediate predictors?
Gender effect
If patients undergo pre-op revascularization…
– Is the combined risk less than surgery alone?
– Does revascularization significantly lower the cardiac risk?
– Does recovery time unduly delay surgery?
References
• ACC/AHA Guideline Update on Perioperative Cardiovascular Evaluation for
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Noncardiac Surgery.
“ACC/AHA Guideline Update for Perioperative CV evaluation for Noncardiac
surgery.” Anesthesia & Analgesia, Volume 94(5), May 2002.
“Beta-blockers and Reduction of Cardiac Events in Noncardiac
Surgery:Clinical Applications” JAMA Volume 287(11) 20 March 2002.
“Critical Review of the ACC/AHA Algorithm for Stratifying Cardiac Patients
for Noncardiac Surgery.” International Anesthesiology Clinics Volume 39(4),
Fall 2001.
“Perioperative Evaluation and Managements of Patients with known or
suspected CV disease…” Hurst’s The Heart McGraw-Hill, 11th edition, New
York, 2004.
“Preoperative Assessment of the Patient with Cardiac Disease” Refresher
Courses in Anesthesiology Volume 33(1) 2005.
www.americanheart.org
www.acc.org
Questions