PREOP CARDIAC EVALUATION FOR NONCARDIAC SURGERY
PREOPERATIVE CARDIAC EVALUATION FOR NONCARDIAC SURGERY (PART-1)Moderator- Dr. Mamta SharmaPresented by - Dr. SudhanshuINTRODUCTIONPreoperative risk assessment is an important step in reducing perioperative morbidity and mortality in patients undergoing non cardiac surgery.
Successful perioperative evaluation is best achieved by combining an integrated multidisciplinary approach with good communication between the patient, primary care physician, anesthesiologist, consultant, and surgeon. GOALSIdentify patients at risk through History, Physical examination, & ECGTo Evaluate severity of underlying cardiac disease, Perform specialized test only on High risk PatientsStratify the Extent of Risk & determine The need for preop intervention to minimize the risk of perioperative cardiac complicationsThe goal of appropriate preoperative evaluation and therapy should be to not only improve immediate periprocedural outcomes but also to improve long term clinical outcome.
Cornerstone of Preoperative cardiac examination includes-Review of HistoryPhysical ExaminationDiagnostic Tests Knowledge of planned surgical procedureEight Steps to the Best Possible Outcome
Assess the Patients Clinical FeaturesEvaluate Functional StatusConsider the Patients Surgery-Specific RiskDecide if Further Noninvasive Evaluation Is NeededDecide When to Recommend Invasive EvaluationOptimize Medical TherapyPerform Appropriate Perioperative SurveillanceDesign Maximal Long-Term TherapyHistoryPresence, severity & reversibility of Heart diseaseRisk factors-AgeHypertensionDiabetes MellitusHyperlipidemiaCigarette SmokingAlcoholFamily History of heart disease- HOCM, Marfan syndrome, Long Q-T syndrome
6History Cont.Chest painShortness of breathAnkle swelling/ peripheral oedemaPalpitations- sensation of the heart beating in the chestSyncopeIntermittent claudication
Chest PainCharacter of painSeverityDurationRadiationAt rest or on exertionPrevious episodes
Relieving factorsWorse on taking a deep breath (pleuritic)Worse on movementAutonomic symptomsSweatingNausea
TypeCauseCharacteristicsAnginaCoronary stenosis (rarely aortic stenosis, hypertrophic cardiomyopathy)Precipitated by exertion, eased by rest and/or glyceryl trinitrate Characteristic distributionMyocardial infarctionCoronary occlusionSimilar sites to angina, more severe, persists at restPericarditic painPericarditisSharp, raw or stabbing Varies with movement or breathingAortic painDissection of the aortaSevere, sudden onset, radiates to the backChest Pain
Causes of Chest PainCardiovascularAnginaStableUnstableMyocardial infarctionAortic dissectionMyocarditisPleuropericardialPericarditisPleurisyPneumothoraxGastrointestinalGastro-oesophageal refluxOesophageal spasm
Chest wallCoughingIntercostal muscle strain/myositisHerpes zosterViral pleurodyniaThoracic radiculopathyRib fractureRib tumourCostochondritisDyspnoea Unexpected awareness of breathingAt rest or on exertionQuantify exercise tolerance (yards walked, stairs climbed)Orthopnoea - shortness of breath on lying supineParoxysmal nocturnal dyspnoeaCauses of DyspnoeaCardiacLeft ventricular failureMitral valve diseaseCardiomyopathyPericardial effusion
Airways diseaseCOPDChronic bronchitisEmphysemaAsthmaBronchiectasisCystic fibrosisPulmonary vasculaturePulmonary embolismPulmonary hypertension
Parenchymal disease PneumoniaPulmonary fibrosisTumourPneumothorax
Chest wallPleural effusionRib fractureKyphoscoliosisNeuromuscularOtherAnaemiaAcidosisPsychogenicNew York Heart Association classification of heart failure symptom severityClass INo limitations. Ordinary physical activity does not cause undue fatigue, dyspnoea or palpitation (asymptomatic left ventricular dysfunction)Class IISlight limitation of physical activity. Such patients are comfortable at rest. Ordinary physical activity results in fatigue, palpitation, dyspnoea or angina pectoris (symptomatically 'mild' heart failure)Class IIIMarked limitation of physical activity. Less than ordinary physical activity will lead to symptoms (symptomatically 'moderate' heart failure)Class IVSymptoms of congestive cardiac failure are present even at rest. With any physical activity increased discomfort is experienced (symptomatically 'severe' heart failure)PERIPHERAL OEDEMAUnilateral or bilateral legsPitting/non-pittingCardiac causes-Congestive cardiac failureRight ventricular failureCor pulmonaleConstrictive pericarditis
DrugsCalcium channel blockersOtherCirrhosis Nephrotic syndromeProtein-losing enteropathyDeep vein thrombosisHypothyroidismLymphoedemaPalpitations Unexpected awareness of heartbeatAsk about-The mode of onset and terminationSpecific triggers of exercise, alcohol, caffeineFrequencyDuration of attacksRhythm (ask patient to tap out).
CausesSinus tachycardiaVentricular extrasystolesAtrial fibrillationAtrial flutterSupraventricular tachycardiaVentricular tachycardia15Syncope Transient loss of consciousness due to cerebral hypo-perfusion -Left ventricular outflow obstruction, postural hypotension, arrhythmiasWhat was the patient doing at the time?Standing up suddenly (postural hypotension)CoughingProdromal symptomsAbnormal movements (epilepsy)Sensation of room spinning (vertigo)Intermittent ClaudicationPain in one or both calves, thighs or buttocksBrought on by walking a certain distance (claudication distance)Worse on walking uphillRelieved by restSuggests peripheral vascular diseasePast Medical HistoryRheumatic feverCong Heart disease- episode of cyanotic/ tet spellsValvular Heart diseasePrevious cardiac investigationsPrevious myocardial infarctionCoronary angioplasty + stent insertionCoronary artery bypass graftingPacemaker insertion
Non cardiac symptomsSystemSymptomCauseCentral nervous systemStrokeCerebral embolismEndocarditisHypertensionGastrointestinalJaundiceLiver congestion secondary to heart failureAbdominal painMesenteric embolismRenalOliguriaHeart failureMedicationsAnti-anginal agentsUse of sublingual nitrate sprayAntihypertensive agentsAnti-arrhythmicsStatinsPlatelet inhibitors, e.g., AspirinAnticoagulants, e.g., Warfarin
Allergies Social HistoryOccupatione.g., train driver, long distance truck driverSmokingNumber of pack yearsAlcohol intakeStairs at homeFamily HistoryIschaemic heart diseaseAnginaMICABGHypertrophic obstructive cardiomyopathyDilated cardiomyopathyAssessment of Functional Capacity The metabolic equivalent, or MET, is defined as the ratio of a person's working metabolic rate relative to the resting metabolic rate. One MET represents the oxygen consumption of a resting adult (3.5 ml/kg/min).In the Revised cardiac risk index by Lee et al functional status was not independently associated with risk. If patients reduce exertion because of cardiac symptoms but still meet a 4-MET threshold, clinicians will underestimate risk. Conversely, non cardiac functional limitations (e.g., knee or back pain) may falsely overestimate cardiac risk.
23Dukes Activity Status Index 1 METCan you take care of yourself?4 METsClimb a flight of stairs or walk up a hill?Eat, dress, or use the toilet?Walk on level ground at 4 mph or 6.4 km/hr?Walk indoors around the house?Run a short distance?Walk a block or two on level ground at 2-3 mph or 3.2-4.8 km/hr?Do heavy work around the house, such as scrubbing floors or lifting or moving heavy furniture?4 METsDo light work around the house, such as dusting or washing dishes?Participate in moderate recreational activities such as playing golf, bowling, dancing, playing doubles tennis, or throwing a baseball or football?10 METs
Participate in strenuous sports such as swimming, singles tennis, football, basketball or skiing?24Physical ExaminationGeneral-pallor, cyanosisHandsPulseBlood pressureFaceNeckJugular venous pressurePre-cardiumInspectionPalpationPercussionAuscultationBackAbdomenLower limbs
Examination - GeneralPosition patient at 45 degreesRespiratory rateCachexiaMarfans syndromeDowns syndrome
Examination - HandsClubbing Splinter haemorrhages (infective endocarditis)Oslers nodes (tender)Janeway lesions (non-tender)Xanthomata (Hyperlipidaemia)
ClubbingSplinter HaemorrhagesExamination - PulseRadial arteryRate (normal = 60-100)Bradycardia (100)RhythmRegularIrregularRadiofemoral delay (coarctation of the aorta)
Character and volume, assessed from carotid arteryCollapsing pulse (aortic regurgitation)Pulsus alternans (left ventricular failure)Pulse deficit (atrial fibrillation)
Dorsalis pedis pulsePosterior tibial pulsePeripheral PulsesExamination - Blood PressureSystolic/diastolic pressureNormal 20 mmHg) fall in systolic blood pressure on standing, diuretic vasdilator31
Examination Face and NeckJaundiceXanthelasmataCorneal arcusMalar flush (mitral stenosis)High arched palate (Marfans syndrome)Dental caries (infective endocarditis)
Central cyanosis Carotid pulse characterSlow rising (AS)Bisferiens (AS + AR)Collapsing (AR)Alternans (LVF)Jerky (HOCM)Carotid bruitEye signs in Hyperlipidaemia
CORNEAL ARCUSXANTHELASMATAJVP
Jugular Venous PressurePatient at 45 degreesGood lightingInternal jugular veinReflects right atrial pressureZero point = sternal angleVisible but not palpableComplex wave form (a, c, v waves) Decreases on inspiration
Hepatojugular refluxAbnormal if >3 cm above zero point:RV failureRV infarctTricuspid stenosisTricuspid regurgitationPericardial effusionSVC obstructionFluid overload
Jugular venous pressure in a healthy subject.(A) Supine: jugular vein distended, pulsation not visible. (B) Reclining at 45: point of transition between distended and collapsed vein can usually be seen to pulsate just above the clavicle. (C) Upright: upper part of vein collapsed and transition point obscuredjugular venous pressure. Form of the venous pulse wave tracing from the internal jugular vein: a = atrial systole; c = transmitted pulsation of carotid artery at onset of ventricular systole; v = peak pressure in right atrium immediately prior to opening of tricuspid valve; a - x = descent, due to atrial relaxation; v - y = descent at commencement of ventricular filling.
Heart failureElevation, sustained abdominojugular refluxPulmonary embolismElevationPericardial effusionElevation, prominent 'y' descentPericardial constrictionElevation. Kssmaul's signSuperior vena caval obstructionElevation, loss of pulsationAtrial fibrillationAbsent 'a' wavesTricuspid stenosisGiant 'a' wavesTricuspid regurgitationGiant 'v' wavesComplete heart block'Cannon' wavesAbnormalities of the jugular venous pulsePrecordium - InspectionScarsMedian sternotomyCABGValve replacementLateral thoracotomyInfraclavicular (pacemaker)Pectus excavatumPacemaker boxApical impulse
Sternotomy scarPectus excavatumPrecordium - PalpationApex beat-Lt 5th ICS medial to the midclavicular lineLocationCharacterHeavingThrustingDoubleTappingParadoxicalLeft parasternal heaveThrills (palpable murmurs)SystolicDiastolicPalpable P2 (pulmonary hypertension)Pacemaker box
Precordium AuscultationHeart SoundsBell low pitched soundsDiaphragm high pitched soundsMitral Tricuspid Pulmonary Aortic areasS1 (first heart sound)S2 Splitting (A2, P2)
Normal Heart Sounds
Precordium AuscultationMurmursTiming of murmurSystolicDiastolicContinuousSite of maximal intensityLoudnessGrades I-VIThrill
PitchRadiationDynamic manoeuvresRespirationLeft-sided on exp.Right-sided on insp.ValsalvaSquatting
Grading of MurmurHeard by an expert in optimum conditionsHeard by a non-expert in optimum conditionsEasily heard; no thrillA loud murmur, with a thrillVery loud, often heard over wide area, with thrillExtremely loud, heard without stethoscope
Heart MurmursSystolicPansystolicMitral regurgitationTricuspid regurgitationVentricular septal defectEjection systolicAortic stenosisPulmonary stenosisHOCMAtrial septal defectLate systolicMitral valve prolapseDiastolicEarly diastolicAortic regurgitationPulmonary regurgitationMid-diastolicMitral stenosisTricuspid stenosisAtrial myxomaContinuousPatent ductus arteriosusArteriovenous fistulaPericardial friction rub
Examination BackPercuss and auscultate lung basesLeft ventricular failurePleural effusionSacral pitting oedemaRight heart failureExamination - AbdomenTender hepatomegalyPulsatile liver (tricuspid regurgitation)AscitesSpleenomegalyAbdominal aortic aneurysmExamination Lower LimbsPeripheral oedemaPitting/non-pittingUpper levelAchilles tendon xanthomataCapillary returnTrophic skin changesPalpate arteriesFemoralPoplitealPosterior tibialDorsalis pedisBuergers test (peripheral vascular disease)
Examination - OtherUrinalysis Haematuria (infective endocarditis)FundiHypertensive retinopathyRoth spots (infective endocarditis)Temperature chartInfective endocarditis
InvestigationRoutine-CXRECG
Specialized tests-Non invasive testsInvasive Tests
Chest X-RAYNon invasive method of estimating cardiac functionPreoperative screening toolProvides useful information in both coronary artery disease and valvular heart diseasePA and Lateral viewRt border-SVC and RALt Border-Aorta, Main Pulmonary artery, Lt Atrial appendages, Anterolateral Border of LV CHEST X RAY.A- AIRWAYB-BONESC-CARDIAC SILHOUTTED-DIAPHRAGME-EDGE OF HEART AND EXTERNAL SOFT TISSUEF- FIELDSG- GASTRIC BUBBLEH-HILA
NORMAL ANATOMY
Normal CXR
Normal posteroanterior chest X-ray.Note vertebral outlines just seen through the heart shadow. A/B - the cardiothoracic ratio should be < 50%.Changes in different cardiac diseasesRA enlargement can be detected by broadening of right heart contourLA enlargement leads to displacement of LA appendage laterally and lt. Bronchus upwards
In massive LA enlargements rt border of LA may overlap rt heart border DOUBLE HEART SHADOWRegurgitant lesion- Long axis is elongated with downward and leftward displacement of apexCAD- both long axis short axis enlargment- globular shaped heartRV enlargement Lat view- Obliteration of retrosternal spaceCHFDIFFUSE B/L ALVEOLAR OPACITIESHAZZINESS OF VASCULAR MARKINGSCARDIOMEGALY-maximum diameter is more than half the internal trans-thoracic diameter (cardiothoracic ratio) in inspiration PA view
Kerley B Lines
Short (1 -2 cm) white lines at the lung bases, perpendicular to the pleural surface representing distended interlobular septaWhat do the arrows indicate?Pulmonary Oedema
Normal Chest RadiographPulmonary OedemaPericardial effusionCardiomegalyNarrow pedicleOlegemic lungsBroad based heartMargins clear
PLEURAL EFFUSION75ml of fluid is needed to obliterate the posterior cp angleMeniscus signLamellar effusions may spare the cp angleUltrasound is more valuable
Mitral stenosisBulging on rt side- double cardiac shadowProminence of LA appendage, straightening of left heart borderElevation of lt main bronchus
TOF
ECGIn standard 12 lead ECG Look for- rate, rhythm, axis, abnormality of p waves, QRS complex, t wave, ST segment, PR, QT & R-R intervals Detect -MIST-T changesQ WavesChamber enlargement-Voltage, strain criteriaArrhythmias- conduction abnormality
67ECG
Anteroseptal- V1-V4Anterolateral- V4-V6Inferior leads: II,III,aVfPost. Wall: Reciprocal Changes in V1-V4Left axis Deviation
LVH
voltage criteria for LVH :The sumof the S wave in v1 or v2, PLUS the R wave in v5 or 635mm, OR, Thesum of the deepest S wave + the tallest R wave > 40mAnysingle, R or S, wavein leads v1-v645mm LVH+hypertension or aortic stenosis, a 'strain pattern' is often seen:ST depression + flipped asymmetric T waveST elevation + upright asymmetric T waveThe strain pattern is greatest in the lead with the tallest/deepest QRS complex.
Acute Anteroseptal MI
Indications for preoperative cardiac testing : 1. Patients with intermediate clinical predictors. 2. Prognostic assessment of patients undergoing initial evaluation for suspected or proven CAD. 3. Evaluation of patients with change in clinical status. 4. Evaluation of adequacy of medical treatment 5. Prognostic assessment after an acute coronary syndrome.
73Noninvasive tests1.Resting tests Ambulatory ECG monitoring.Resting ECHO.2.Trans esophageal echocardiography3.Exercise stress test.4.Pharmecological stress testDSE.DTS.5.Nuclear imaging74Ambulatory Electrocardiography (24 h Holter monitoring)Continuous ECG monitoring of ambulatory pt by tape recorder (holter monitoring)Used to evaluate cardiac arrhythmias, antiarrhythmic drug therapy and severity frequency of ischemic episodeCorrelation of symptom( palpitation dizziness syncope) are often most valuable result of recordingSilent ischemic episode are frequent findingPreoperative occurrence of frequent ischemic episodes correlates well with intraoperative & postop. Ischemia. Relatively inexpensive
24-hour ambulatory ECG recording, showing complete heart block.Arrows indicate visible P waves; at times these are masked by the QRS complex or T waveResting EchocardiographySimple and inexpensiveIndication- Detection of impaired LV function, valvular heart diseaseInformation-RWMA- Types-Hypo/akinesia, dyskinesia Location-ant, septal, lat, inf, post.Ejection FractionChamber EnlargementValve morphology, Diagnosis of cong. Heart disease
TEEProvide Clearer images- heart rests directly upon the esophagus leaving only millimeters that the ultrasound beam has to travel. This reduces the attenuation of the ultrasound signal, generating a stronger return signal, ultimately enhancing image and Doppler quality.Valuable in diagnosis of MI, VHD complicated cong heart disease , and assessment of ventricular function (Morbid Obese pt) very high sensitivity for locating a blood clot inside the left atriumDisadvantage- may require anaesthesia, fasting of ptEsophageal perforation cases has been reported
Exercise Stress Testing(Treadmill)Physiology-Mean arterial Pressure Increases despite significant decrease in SVR Due to increase in cardiac output ( Upto 4X)HR increase by upto 300%Stroke volume increase by upto 20%Increase in Oxygen consumption is meet mainly by increasing blood flow (vasodilatation by exercise and metabolites)Coronary vascular reserve play imp role in ischemic heart response to exercise
Bruce Treadmill protocolsConsists of 3 min stages having different grade and speedStage 1= 1.7mph & 10% gradeSign and symptom of ischemia, arrythmias and pump dysfunction measuredPrincipal indicator of ischemia- ST segment deviation3 types of response-ST segment depression during exercise, normal in post exercise period ST segment depression during exercise, worsening in recovery periodST segment elevation Accepted criteria- elevation of 1.5 mm or moreChanges in T wave, R wave, hypotension chest pain arrhythmias also considered.
Information by TMTPeak heart Rate, Systolic BP & double productMETS& % of Heart rate achievedECG changes, symptoms, or arrhythmias occurring during test & at recovery periodA pt with symptoms or arrhythmias at a lower workload is at increase risk as compared with a patient able to reach a higher MET thresholds. Double pressure product must remain below the ischemic thresholds.
Limitation & Interpretation of TMTOnly Half of the pt achieve peak HR>75% of his age predicted maximumA ve test in a pt. who achieves target HR BP product is usually associated with low risk for perioperative cardiac complicationIschemia induced by low level exercise indicates high riskFailure to reach the target HR makes the test inadequate for excluding MI unless a normal workload is achieved despite lower HR and such pt. are at higher risk for perioperative complication.PPV=18% NPV=97%
Dipyridamole-thallium scintigraphyDipyridamole- Powerful coronary dilatorMOA- preventing uptake and degradation of adenosine(auto-regulate coronary flow in response to ischemia)Distribute blood to normal coronary and reduce blood flow Distal to ischemia (coronary steal phenomena )Thallium demonstrate myocardium at riskTheophylline caffine avoided before test( antagonist)S/E- Bronchospasm, chest pain, headacheReversed by iv AminophyllineDobutamine stress echocardiographystress testing should be limited to patients with suspicion of a myocardium at risk of ischemiaMOA- Dobutamine increase myocardial oxygen demand , increase HR, and inotropyDetect new or worsened RWMA & severityBaseline ejection fractionAvoided in pt with- Arrythmias, marked Hyper/Hypotension, critical ASNuclear imagingMyocardial perfusion scan using thallium 201 & Technetium 99 pyrophosphate.Useful in pt. who can not exerciseAssessment of perfusion, infarction & ventricular functionHot spot technique(Tech-99) Infarcted segment is detected as hot spot by gamma cameraCold spot technique-th201 taken by areas with normal perfusion , cold spot represent area of decreased perfusion
Coronary angiographyTo situations where revascularization can improve long-term survival- Unstable coronary syndromeInformation about coronary artery and presence and pattern of atherosclerotic disease, specially suspected left main or triple vessel diseases.Intra cardiac pressure and cardiac outputAnatomy of cong. Heart disease. Grading of Ejection fraction55-75% -Normal contracting left ventricle 40-55%-Decrese myocardial contractalty Either due to previous MI or increase afterload due to hypertension- usually asymptomatic25-40%- Pt symptomatic During Exercise.55%LVEDP 2.5 ltr/min/m2No area of ventricular dyskinesia
Impaired FunctionEF< 40%LVEDP>18 mm hgCardiac index< 2ltr/min/m2Multiple areas of ventricular dyskinesia
CONCLUSIONThorough history,Detailed physical examination,Judicious use of tests.Categorize patients into low, intermediate & high riskCombine preop assessment with periop risk reduction strategies & optimize medical treatment to improve outcome.
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