Pre-operative Assessment Pre-operative Assessment of the Surgical Patientof the Surgical Patient

Augusto Torres, MDAugusto Torres, MDDepartment of AnesthesiologyDepartment of AnesthesiologyMetroHealth Medical CenterMetroHealth Medical Center

July 2007

OutlineOutline

Discuss anesthesia Discuss anesthesia specific riskspecific riskDiscuss patient Discuss patient specific riskspecific riskSurgery specific riskSurgery specific riskPre-operative Pre-operative laboratory and studieslaboratory and studiesExample caseExample case

Reason for evaluationReason for evaluationAnesthesia and surgery are physiologically Anesthesia and surgery are physiologically stressful, invasive interventions which may stressful, invasive interventions which may exacerbate or uncover underlying disease exacerbate or uncover underlying disease processesprocessesSome of the most feared complications include Some of the most feared complications include catastophic events such as myocardial catastophic events such as myocardial infarction,difficulty oxygenating or ventilating, infarction,difficulty oxygenating or ventilating, and cerebral vascular accident, among othersand cerebral vascular accident, among othersA proper pre-operative assessment allows the A proper pre-operative assessment allows the perioperative providers (anesthesiologist and perioperative providers (anesthesiologist and surgeon) the ability to stratify and reduce risk for surgeon) the ability to stratify and reduce risk for the patientthe patient

Why is anesthesia risky?Why is anesthesia risky?There can be difficulty obtaining an airway to adequately There can be difficulty obtaining an airway to adequately oxygenate and ventilateoxygenate and ventilateInduction (i.e. “going to sleep”): time of hemodynamic Induction (i.e. “going to sleep”): time of hemodynamic stress – patient may become hypotensive from the stress – patient may become hypotensive from the induction agents or hypertensive with laryngoscopy and induction agents or hypertensive with laryngoscopy and intubationintubationMaintanence (bulk of case): differing degrees of Maintanence (bulk of case): differing degrees of stimulation, fluid shifts, blood lossstimulation, fluid shifts, blood lossEmergence (i.e. “waking up”): physiologically stressful, Emergence (i.e. “waking up”): physiologically stressful, secure airway may be lost, hypothermiasecure airway may be lost, hypothermiaAnaphylactic reactions to medications, injury during Anaphylactic reactions to medications, injury during laryngoscopy, neuropathy from positioninglaryngoscopy, neuropathy from positioningEven spinal/epidural carries risk: inadequate, need to Even spinal/epidural carries risk: inadequate, need to convert to general, sympathectomy with vasodilation, etcconvert to general, sympathectomy with vasodilation, etc

ACC/AHA Guideline Update for ACC/AHA Guideline Update for Perioperative Cardiovascular Evaluation for Perioperative Cardiovascular Evaluation for Noncardiac Surgery – Executive Summary Noncardiac Surgery – Executive Summary

Published in 2002 in Published in 2002 in Circulation 105:1257-Circulation 105:1257-1267.1267.Eagle KA et alEagle KA et alGuidelines for evaluation of cardiac riskGuidelines for evaluation of cardiac risk

Clinical Predictors of Increased Clinical Predictors of Increased Perioperative Cardiovascular RiskPerioperative Cardiovascular RiskMAJORMAJOR– Unstable coronary syndromesUnstable coronary syndromes

Acute (<7d) or recent MI (<1mo) with evidence of ischemic Acute (<7d) or recent MI (<1mo) with evidence of ischemic riskriskUnstable or severe anginaUnstable or severe angina

– Decompensated heart failureDecompensated heart failure– Significant arrhythmiasSignificant arrhythmias

High-grade AV blockHigh-grade AV blockSymptomatic ventricular arrhythmiaSymptomatic ventricular arrhythmiaSVT uncontrolled rateSVT uncontrolled rate

– Severe valvular diseaseSevere valvular disease

Clinical Predictors of Increased Clinical Predictors of Increased Perioperative Cardiovascular RiskPerioperative Cardiovascular RiskINTERMEDIATEINTERMEDIATE– Mild angina pectorisMild angina pectoris– Previous myocardial infarction (>1mo) by Previous myocardial infarction (>1mo) by

history of pathological Q waveshistory of pathological Q waves– Compensated or prior heart failureCompensated or prior heart failure– Diabetes mellitus (particularly insulin Diabetes mellitus (particularly insulin

dependent)dependent)– Renal insufficiency (creatinine >2.0)Renal insufficiency (creatinine >2.0)

Clinical Predictors of Increased Clinical Predictors of Increased Perioperative Cardiovascular RiskPerioperative Cardiovascular RiskMINORMINOR– Advanced ageAdvanced age– Abnormal ECG (LVH, LBBB, ST-T Abnormal ECG (LVH, LBBB, ST-T

abnormalities)abnormalities)– Rhythm other than sinus (e.g. a fib)Rhythm other than sinus (e.g. a fib)– Low functional capacity (e.g. inability to climb Low functional capacity (e.g. inability to climb

one flight of stairs with a bag of groceries)one flight of stairs with a bag of groceries)– History of strokeHistory of stroke– Uncontrolled systemic hypertension Uncontrolled systemic hypertension

Clinical Predictors of Increased Clinical Predictors of Increased Perioperative Cardiovascular RiskPerioperative Cardiovascular RiskFunctional CapacityFunctional Capacity– Metabolic equivalentsMetabolic equivalents– 1 MET – Can you take care of yourself? Eat, 1 MET – Can you take care of yourself? Eat,

dress, use the toilet? Walk a block or two on dress, use the toilet? Walk a block or two on level ground 2-3 MPHlevel ground 2-3 MPH

– 4 METs – Do light work around the house like 4 METs – Do light work around the house like dusting or washing the dishes? Climb a flight dusting or washing the dishes? Climb a flight of stairs?of stairs?

– >10 METs – Participate in strenuous sports >10 METs – Participate in strenuous sports like swimming, singles tennis, football?like swimming, singles tennis, football?

Clinical Predictors of Increased Clinical Predictors of Increased Perioperative Cardiovascular RiskPerioperative Cardiovascular RiskFunctional CapacityFunctional Capacity– Perioperative cardiac and long-term risks are Perioperative cardiac and long-term risks are

elevated in patients unable to obtain 4-MET elevated in patients unable to obtain 4-MET demanddemand

– www.1000takes.comwww.1000takes.com

Surgery-specific riskSurgery-specific risk

Two important factorsTwo important factors– The type of surgery and degree of The type of surgery and degree of

hemodynamic stresshemodynamic stress

Surgery Specific RiskSurgery Specific RiskHigh (Reported risk High (Reported risk >5%)>5%)– Emergent major Emergent major

operations, particularly operations, particularly in elderlyin elderly

– Aortic and other major Aortic and other major vascular surgeryvascular surgery

– Surgical procedures Surgical procedures associated with large associated with large fluid shifts and/or blood fluid shifts and/or blood lossloss

– www.services.epnet.comwww.services.epnet.com

Surgery Specific RiskSurgery Specific Risk

Intermediate Intermediate (Reported risk <5%)(Reported risk <5%)– Carotid Carotid

endarterectomyendarterectomy– Head and neck surgeryHead and neck surgery– Intraperitoneal and Intraperitoneal and

intrathoracic intrathoracic proceduresprocedures

– Orthopedic surgeryOrthopedic surgery– Prostate surgeryProstate surgery

Surgery Specific RiskSurgery Specific Risk

Low (Reported risk Low (Reported risk <1%)<1%)– Endoscopic Endoscopic

proceduresprocedures– Superficial proceduresSuperficial procedures– Cataract surgeryCataract surgery– Breast surgeryBreast surgery– www.steenhall.comwww.steenhall.com

The AlgorithmThe Algorithm

Step 1: What is the urgency of surgery?Step 1: What is the urgency of surgery?– Emergency: No time for further evaluationEmergency: No time for further evaluationStep 2: Coronary revascularization in the Step 2: Coronary revascularization in the past five years?past five years?– Free ticket for five years if no new symptoms Free ticket for five years if no new symptoms

have arisen (chest pain or SOB)have arisen (chest pain or SOB)Step 3: Coronary evaluation in the past 2 Step 3: Coronary evaluation in the past 2 years?years?– Free ticket for two years if no new symptomsFree ticket for two years if no new symptoms

The AlgorithmThe AlgorithmStep 4: Unstable coronary syndrome or major Step 4: Unstable coronary syndrome or major predictor of risk?predictor of risk?– Will lead to cancellation or delay of surgeryWill lead to cancellation or delay of surgeryStep 5: Intermediate clinical predictors of risk?Step 5: Intermediate clinical predictors of risk?Step 6: Step 6: – Intermediate clinical predictors and moderate to Intermediate clinical predictors and moderate to

excellent functional capacity are good candidates for excellent functional capacity are good candidates for intermediate risk surgeryintermediate risk surgery

– Intermediate clinical predictors and poor functional Intermediate clinical predictors and poor functional capacity or moderate to excellent functional capacity capacity or moderate to excellent functional capacity with high risk surgery often need further testingwith high risk surgery often need further testing

The AlgorithmThe Algorithm

Step 7: Step 7: – Minor or no clinical predictors with moderate Minor or no clinical predictors with moderate

or excellent functional capacity usually need or excellent functional capacity usually need no further testingno further testing

– Minor or no clinical predictors with poor Minor or no clinical predictors with poor functional capacity and high risk surgery may functional capacity and high risk surgery may need further testingneed further testing

Step 8: Results of non-invasive testing Step 8: Results of non-invasive testing determines need for invasive testing or determines need for invasive testing or interventionintervention

Pre-operative TestsPre-operative Tests

12-Lead ECG12-Lead ECG– Class I: Recent episode of chest pain or Class I: Recent episode of chest pain or

ischemic equivalent etcischemic equivalent etc– Class IIB: Class IIB:

Prior coronary revascularizationPrior coronary revascularizationAsymptomatic male >45yrs old or female >55 yrs Asymptomatic male >45yrs old or female >55 yrs old with 2 or more risk factorsold with 2 or more risk factorsPrior hospital admission for cardiac causesPrior hospital admission for cardiac causes

– Class III: Routine in asymptomatic individualsClass III: Routine in asymptomatic individuals

Pre-operative TestsPre-operative Tests

EchoEcho– Class I: Patients with current or poorly Class I: Patients with current or poorly

controlled heart failurecontrolled heart failure– Class IIa: Prior heart failure and dyspnea of Class IIa: Prior heart failure and dyspnea of

unknown originunknown origin– Class III: As a routine testClass III: As a routine test

Pre-operative TestsPre-operative Tests

Exercise or Pharmacological Stress Exercise or Pharmacological Stress TestingTesting– Class I: Class I:

Patients with intermediate pretest probabilityPatients with intermediate pretest probabilityChange in clinical status of patient with suspected Change in clinical status of patient with suspected or proven CADor proven CADProof of ischemia prior to revascularizationProof of ischemia prior to revascularizationEvaluation of adequacy of medical therapyEvaluation of adequacy of medical therapy

– Class IIa: Evaluation of exercise capacity Class IIa: Evaluation of exercise capacity when subjective assessment unreliablewhen subjective assessment unreliable

Pre-operative TestsPre-operative Tests

Class IIbClass IIb– Diagnosis of CAD in patients with high or low Diagnosis of CAD in patients with high or low

pretest probability: resting ST depression pretest probability: resting ST depression <1mm, taking digitalis, or LVH<1mm, taking digitalis, or LVH

– Detection of restenosis in high-risk Detection of restenosis in high-risk asymptomatic patientsasymptomatic patients

Class IIIClass III– Routine screening of asymptomatic patientsRoutine screening of asymptomatic patients

Pre-operative TestsPre-operative Tests

Coronary AngiographyCoronary Angiography– Class IClass I

Evidence of adverse outcome from non-invasive Evidence of adverse outcome from non-invasive testtestAngina unresponsive to therapyAngina unresponsive to therapyUnstable angina, especially with intermediate or Unstable angina, especially with intermediate or high risk surgeryhigh risk surgeryEquivocal noninvasive test in high clinical risk Equivocal noninvasive test in high clinical risk patient undergoing high risk surgerypatient undergoing high risk surgery

Pre-operative TestsPre-operative Tests

Class IIaClass IIa– Multiple markers of intermediate clinical risk Multiple markers of intermediate clinical risk

and planned vascular surgeryand planned vascular surgery– Moderate to large ischemia on non-invasive Moderate to large ischemia on non-invasive

testing but without high-risk features and testing but without high-risk features and lower left ventricular functionlower left ventricular function

– Nondiagnostic noninvasive test results in Nondiagnostic noninvasive test results in patients at intermediate clinical riskpatients at intermediate clinical risk

– Urgent noncardiac surgery while recovering Urgent noncardiac surgery while recovering from acute MIfrom acute MI

Pre-operative TestsPre-operative Tests

Class IIbClass IIb– Perioperative MIPerioperative MI– Medically stabilized angina and low-risk surgeryMedically stabilized angina and low-risk surgery

Class IIIClass III– Low risk surgery with known CADLow risk surgery with known CAD– Asymptomatic after coronary revascularization with Asymptomatic after coronary revascularization with

excellent exercise capacityexcellent exercise capacity– Noncandidate for coronary revascularization owing to Noncandidate for coronary revascularization owing to

concomitant medical illness, severe left ventricular concomitant medical illness, severe left ventricular dysfunction (EF <20%)dysfunction (EF <20%)

Perioperative TherapyPerioperative Therapy

CABGCABG– Indications for CABG same as for those not Indications for CABG same as for those not

undergoing surgeryundergoing surgery– Consider in those who long-term outcome Consider in those who long-term outcome

improved by CABGimproved by CABG

Percutaneous Coronary InterventionPercutaneous Coronary Intervention– Delay of 4-6 weeks for antiplatelet therapy for Delay of 4-6 weeks for antiplatelet therapy for

re-endothelializationre-endothelialization

Day of SurgeryDay of Surgery

History of present illnessHistory of present illnessNPO statusNPO statusPMHPMHPSH PSH – Problems with anethesiaProblems with anethesia

Malignant hyperthermiaMalignant hyperthermiaPost-operative nausea and vomitingPost-operative nausea and vomitingDifficulty with intubation – letter from Difficulty with intubation – letter from anesthesiologistanesthesiologist

Day of SurgeryDay of Surgery

AllergiesAllergies– Antibiotics, latexAntibiotics, latex

Vital signs (are vital)Vital signs (are vital)– Baseline blood pressure for cerebral autoregulationBaseline blood pressure for cerebral autoregulation

Physical examination (directed)Physical examination (directed)– Airway examinationAirway examination– CorCor– LungsLungs– Neurologic (especially if regional technique planned)Neurologic (especially if regional technique planned)

Day of SurgeryDay of Surgery

LaboratoryLaboratory– Eg. Renal function, starting HCT, PlateletsEg. Renal function, starting HCT, Platelets– Beta HCG women of childbearing ageBeta HCG women of childbearing age

ImagingImaging– CXR: Trauma, CHF, COPDCXR: Trauma, CHF, COPD– CT scan in thyroidectomyCT scan in thyroidectomy

Day of SurgeryDay of Surgery

Assessment of patientAssessment of patient– Risk of anesthesia and surgeryRisk of anesthesia and surgery– MonitoringMonitoring– Technique of anesthesia and agents to be Technique of anesthesia and agents to be

usedused– Post-operative carePost-operative care

Example of PatientExample of Patient59 year old female presents for an Aorto-bifemoral bypass59 year old female presents for an Aorto-bifemoral bypassPMH:PMH:– HTNHTN– DM IIDM II– HypercholesterolemiaHypercholesterolemia

PSH:PSH:– Hysterectomy at age 49Hysterectomy at age 49

Social HX: Tob 35 pack yrSocial HX: Tob 35 pack yrNKDANKDAMeds: atenolol, glucophage, lipitorMeds: atenolol, glucophage, lipitorVS 145/73, P: 71, R:18, Sat 96%VS 145/73, P: 71, R:18, Sat 96%NAD, A&O x3NAD, A&O x3MP 2, Neck FROMMP 2, Neck FROMCor: RRRCor: RRRLungs: BS distant, no wheezingLungs: BS distant, no wheezingAbd: soft, no palpable massAbd: soft, no palpable massExt: lower ext cool, difficult to palpate pulsesExt: lower ext cool, difficult to palpate pulses

Example of PatientExample of Patient59 year old female presents for an 59 year old female presents for an Aorto-bifemoral bypassAorto-bifemoral bypassPMH:PMH:– HTNHTN– DM IIDM II– HypercholesterolemiaHypercholesterolemia

PSH:PSH:– Hysterectomy at age 49Hysterectomy at age 49

Social HX: Tob 35 pack yrSocial HX: Tob 35 pack yrNKDANKDAMeds: atenolol, glucophage, lipitorMeds: atenolol, glucophage, lipitorVS 145/73, P: 71, R:18, Sat 96%VS 145/73, P: 71, R:18, Sat 96%NAD, A&O x3NAD, A&O x3MP 2, Neck FROMMP 2, Neck FROMCor: RRRCor: RRRLungs: BS distant, no wheezingLungs: BS distant, no wheezingAbd: soft, no palpable massAbd: soft, no palpable massExt: lower ext cool, difficult to Ext: lower ext cool, difficult to palpate pulsespalpate pulses

What if any further preoprative What if any further preoprative laboratory or investigative studies laboratory or investigative studies are necessary?are necessary?

LaboratoryLaboratory

Basic metabolic profile?Basic metabolic profile?

CBC? CBC?

Coagulation profile?Coagulation profile?

LaboratoryLaboratory

Basic metabolic profileBasic metabolic profile– Assessment of baseline renal functionAssessment of baseline renal function

CBCCBC– HCT and PlateletsHCT and Platelets

Coagulation profileCoagulation profile– History of bleeding and/or bruisingHistory of bleeding and/or bruising

ECG?ECG?

ECG?ECG?

12-Lead ECG12-Lead ECG– Class IIB: Class IIB:

Asymptomatic male >45yrs old or female >55 yrs Asymptomatic male >45yrs old or female >55 yrs old with 2 or more risk factorsold with 2 or more risk factors

ECGECG

NSR with non-specific ST and T wave NSR with non-specific ST and T wave changeschangeswww.library.med.utah.eduwww.library.med.utah.edu

Chest X-ray?Chest X-ray?

Chest X-rayChest X-ray

Clinical Clinical characteristics to characteristics to consider:consider:– Smoking, COPD, Smoking, COPD,

recent respiratory recent respiratory infection, cardiac infection, cardiac diseasedisease

– If the above are stable, If the above are stable, no unequivocal no unequivocal indicationindication

Further cardiac evaluation?Further cardiac evaluation?

Further cardiac evaluationFurther cardiac evaluation

Clinical predictors?Clinical predictors?– Intermediate i.e. Intermediate i.e. diabetes mellitusdiabetes mellitus

Functional capacity?Functional capacity?

Functional CapacityFunctional Capacity““I can’t walk one flight of I can’t walk one flight of steps because my legs steps because my legs hurt!”hurt!”<4 mets<4 metsNon-invasive testingNon-invasive testingExercise or Exercise or Pharmacological Stress Pharmacological Stress TestingTesting– Class IIa: Evaluation of Class IIa: Evaluation of

exercise capacity when exercise capacity when subjective assessment subjective assessment unreliableunreliable

– www.users.interport.netwww.users.interport.net

Non-invasive testingNon-invasive testingDobutamine stress echoDobutamine stress echo– EF 50%, mildly reduced EF 50%, mildly reduced

ventricular functionventricular function– Area of scar inferior Area of scar inferior

segmentsegment– With injection of With injection of

dobutamine, area of dobutamine, area of hypokinesis lateral hypokinesis lateral segment of the left ventriclesegment of the left ventricle

– www.folk.ntnu.nowww.folk.ntnu.no

Coronary angiography?Coronary angiography?

Coronary angiography?Coronary angiography?Class IClass I

Evidence of adverse Evidence of adverse outcome from non-outcome from non-invasive testinvasive test

Coronary angiogramCoronary angiogram– Left main: normal vesselLeft main: normal vessel– LAD: area of 40% proximalLAD: area of 40% proximal– Circumflex: 80% proximal Circumflex: 80% proximal

lesionlesion– RCA: severe diffuse RCA: severe diffuse

disease with collateral disease with collateral filling from PCAfilling from PCA

– Procedure: one stent Procedure: one stent successfully placed in successfully placed in proximal cirumflex arteryproximal cirumflex artery

Coronary AngiographyCoronary Angiography

Patient placed on plavix and surgery Patient placed on plavix and surgery postponed for six weekspostponed for six weeksPatient, surgeon, and anesthesiologist Patient, surgeon, and anesthesiologist aware of tenuous blood supply to RCA aware of tenuous blood supply to RCA territory but no stress-induced ischemiaterritory but no stress-induced ischemiawww.health.yahoo.comwww.health.yahoo.com

ConclusionConclusion

Preoperative evaluation is necessary to Preoperative evaluation is necessary to stratify risk to the patientstratify risk to the patientThe evaluation delineates patient clinical The evaluation delineates patient clinical factors as well as extent of surgeryfactors as well as extent of surgeryThe patient, surgeon, anesthesiologist are The patient, surgeon, anesthesiologist are aware of the perioperative risk and may aware of the perioperative risk and may plan therapy accordinglyplan therapy accordingly