2At the completion of this presentation, the learner should be able to: Learning ObjectivesAt the completion of this presentation, the learner should be able to:Describe appropriate pre-operative cardiovascular evaluationDescribe appropriate pre-operative pulmonary evaluationManage anticoagulation in the peri-operative periodManage diabetes in the peri-operative periodLocate resources related to the above topics on the internet
3Cardiovascular evaluation Pulmonary evaluation Presentation OutlineCardiovascular evaluationPulmonary evaluationManagement of anticoagulationManagement of diabetesOnline resourcesQuizReferences
5Cardiac Preoperative Evaluation EpidemiologyThe prevalence of cardiovascular disease increases with age.Estimated that the number of people >65 in the US will increase by 25-35% over next 30 years.This is the same population in which the most surgical procedures are performed.Number of noncardiac surgeries may increase from 6 million per year to 12 million per year; some of which have been associated with significant periop cardiac morbidity and mortality.
6Cardiac Preoperative Evaluation ACC/AHA Guideline on Perioperative Cardiovascular Evaluation for Noncardiac SurgeryFirst developed by ACC/AHA Task Force on Practice Guidelines in 1996.Updated in 2002.Provides framework for considering cardiac risk in noncardiac surgeries.Provides tables and algorithms for quick reference and decision making.
7Cardiac Preoperative Evaluation PurposeNot to give “medical clearance”.Perform an evaluation of the patient’s current medical status.Make recommendations concerning the evaluation, management, and risk of cardiac problems over the entire perioperative periodNo test should be performed unless it will influence patient treatment.Must be carefully tailored to the patient and the circumstance.
8Cardiac Preoperative Evaluation Need for noncardiac surgeryUrgent or electiveemergencyCoronary revascularizationWithin 5 years?YESOperate(OK for surgery)Recurrence of symptomsNONORecent coronary evaluationWithin 2 years?YESRecent stress test orCoronary angiogramfavorable resultsYESNOCLINCAL PREDICTORS(see next set of algorithms)Unfavorable results
9Cardiac Preoperative Evaluation Next step is to evaluate the patient’s risk and the inherent riskiness of the surgeryPatient’s risk is determined by clinical predictors and functional capacitySurgery riskiness is determined by the type and site of surgeryOnce patient’s risk and surgery’s risk are known, additional algorithms can be used to determine the appropriate course of action
10Cardiac Preoperative Evaluation: Clinical predictors Clinical Predictors of Increased Perioperative Cardiovascular RiskMajorIntermediateLowUnstable coronary synd٭Mild anginaAdvanced ageDecompensated CHFPrior MI (hx or ECG)Abnormal ECG †Significant arrhythmias#Compensated or prior CHFRhythm other than sinusSignificant valvular dzDiabetes mellitusLow functional capacityRenal insufficiencyHistory of strokeUncontrolled HTN٭acute (within 7 days) or recent (7-30 days) MI or class III or IV symptoms#high grade AV block, symptomatic ventricular arrhythmia with underlying heart disease, or SVT with uncontrolled ventricular rate†LVH, LBBB, ST-T abnormalities
11Cardiac Preoperative Evaluation: Functional capacity Functional capacity is also an important part of the algorithm and relies on “METs”, or metabolic equivalents, to rate a patient’s functionality1 MET is equivalent to a metabolic rate consuming 3.5 milliliters of oxygen per kg of body weight per minute or 1 kilocalorie per kg of body weight per hourIn a treadmill test, actually measuring METs requires that the person being tested wear a mask in order to measure his or her oxygen consumption (and the carbon dioxide exhaled)However, METs can be estimated as follows:1-4 METs: daily activities, walking 1-2 blocks on level ground at 2-3 mph, light housework4-10 METs: climbing stairs or hill, jogging short distance, heavy housework, bowling, dancing, golf, swimming10-14 METs: running (at least an 8-minute mile), downhill skiing, rock climbing, etc.
12Cardiac Preoperative Evaluation: surgical riskiness Cardiac Risk* Stratification for Non-cardiac Surgical ProceduresHigh (>5%)Intermediate (<5%)Low (<1%)Emergent major operations,especially in the elderlyCarotid endarterectomyEndoscopic proceduresMajor vascular or peripheral vascular surgeryHead and neck operationsSuperficial proceduresProlonged surgery with large fluid shifts or blood lossIntraperitoneal and intrathoracic operationsCataract surgeryOrthopedic proceduresBreast surgeryProstate surgery٭combined risk of cardiac death and nonfatal myocardial infarction
13Cardiac Preoperative Evaluation Patient withMAJOR CLINICALPREDICTORSConsider delaying or cancelingnon-cardiac surgeryConsider coronary angiographyMedical management andrisk factor modificationSubsequent care* dictated byfindings and treatment results*subsequent care may include delay or canceling surgery, coronary revascularization followed by non-cardiac surgery, or intensified care.
14Cardiac Preoperative Evaluation Patient with INTERMEDIATECLINICAL PREDICTORSPoor functional capacity(<4 METS)Mod or excellent(>4 METS)highsurgical riskIntermediatesurgical risklowsurgical riskLow riskOperateNoninvasive testingHigh riskConsider coronaryangiographySubsequent care dictated byfindings and treatment results
15Cardiac Preoperative Evaluation Patient with NO OR MINORCLINICAL PREDICTORSPoor functional capacity(<4 METS)Mod or excellent(>4 METS)highsurgical riskIntermediate orlow surgical riskLow riskOperateNoninvasive testingHigh riskConsider coronaryangiographySubsequent care dictated byfindings and treatment results
17Existing literature focuses on: Pulmonary evaluationCurrently no published guidelines are available for the general surgical patientExisting literature focuses on:Evaluation of the lung cancer patient prior to lung resectionEvaluation of risk for post-operative pneumoniaGeneral guidelines are reportedly forthcoming this year
18Evaluation of the lung cancer patient prior to lung resection 30,000 lung resections are performed annuallyMortality rate from lung resection surgery is 7-11%Accurate pulmonary evaluation can predict risk of operative mortality and help stratify patients in terms of treatment options (Beckles 2003, Datta 2003)
19Preoperative evaluation Staged, stepwise assessment to evaluate risk of complications (Beckles 2003, Datta 2003), starting with careful history and physical examination and then proceeding to objective testingStage I assessmentSpirometry / DLCO measurement, +/- ABGIf FEV1>80% predicted or >2L, MVV is >55% predicted, and DLCO is >60% predicted, pt is suitable for resection including pneumonectomy without further evaluationIf pt does not meet these criteria, proceed to stage II testingStage II assessmentQuantitative V/Q scan or differential lung scanIf predicted postoperative (ppo) FEV1 is >40% predicted and ppo DLCO is >40% predicted, pt is suitable for resection including pneumonectomyIf pt does not meet these criteria, proceed to stage III testing
20Preoperative evaluation continued Stage III assessmentExercise testingIf VO2 max is greater than 20 mL/kg/min, pt is suitable for surgeryIf VO2 max is less than 10 mL/kg/min (roughly the ability to walk up one flight of stairs), pt is at greatly increased risk of complications and death from surgery and non-surgical management should be pursuedAlternative algorithm (Wyser 1999)If FEV1 or DLCO <80% predicted, proceed directly to exercise testingIf VO2 max >20, proceed to surgeryIf VO2 max 10-20, undergo quantitative V/Q and calculate ppo values as before
21Evaluation of risk for post-operative pneumonia Why is post-op PNA important?Pneumonia is the 3rd most common postop complication (after UTI, wound infection) (Garibaldi 1981)Pneumonia occurs in 10-40% of patients in the post-op period and carries a mortality of 30-46% (Brooks-Brunn 1997)25% of deaths occurring within 6 days of surgery are pulmonary in etiology (Brooks-Brunn 1995)
22Risk Assessment for Post-op PNA Risk index developed in a sample of 10 VA hospitals using data from the Department of Veterans Affairs National Surgical Quality Improvement Program (NSQIP)160,805 patients in derivation cohort,155,266 patients in validation cohort,2,466 patients developed pneumonia (1.5%), compared with myocardial infarction in only 0.4%Patients with post-op PNA had a 30-day mortality of 21%, compared with only 2% of the remaining patients
23PNA PredictorsMost important predictors (Odds Ratios, OR, listed for those predictors with OR for development of PNA of greater than 1.5):Type of surgeryAAA, OR=4.29Thoracic surgery, OR=3.92Upper abdominal surgery, OR=2.68Neck surgery, OR=2.30Neurosurgery, OR=2.14
24PNA Predictors, continued Age>80, OR=5.6370-79, OR=3.5860-69, OR=2.38Functional status prior to surgeryTotally dependent, OR=2.83Partially depentent, OR=1.83Weight loss > 10% in last 6 months, OR=1.92History of COPD, OR=1.72General anesthesia, OR=1.56“Impaired sensorium,” OR=1.51
25Development of Risk Index Predictors were then turned into a scoring system, based on strength of association, to allow prospective grading of post-operative riskScoring system (“risk index”) was then validated on an independent cohortNotable study limitations: veteran population, very few women, many comorbidities, no data about PFTs was included, no correction for prophylactic antibiotics was possible
26Postoperative PNA Risk Index Preoperative Risk FactorPoint valueType of surgeryAAA repair15Thoracic surgery14Upper abdominal surgery10Neck surgery8NeurosurgeryVascular surgery3Age≥80 years1770-79 years1360-69 years950-59 years4Functional statusTotally dependentPartially dependent6Preoperative Risk FactorPoint valueWeight loss >10% in past 6 months7History of COPD5Receipt of general anesthesia4Impaired sensoriumHistory of CVABlood urea nitrogen level<8 mg/dL22-30 mg/dL2≥30 mg/dL3Transfusion of > 4 units of bloodEmergency surgerySteroid use for chronic conditionCurrent smoker within one yearAlcohol intake > 2 drinks/d in past 2 wksFrom Arozullah et al 2001
27Risk Index and Outcomes Risk Class1(0-15 pts)2(16-25 pts)3(26-40 pts)4(41-55 pts)5(>55 pts)Rate of postop PNA in development cohort, %0.241.194.09.415.8Rate of postop PNA in validation cohort, %1.184.610.815.9
28Pre-op evaluation of coagulation and Peri-op management of anticoagulation
29Management of bleeding risk Management of bleeding risk in the peri-op period requires consideration of risk of bleedingDefining the level of hemostatic risk for the proposed surgery is essentialLow Risk surgery:-nonvital organs are involved-surgical site is exposed-limited degree of surgical dissection-local hemostatic measures are likely to be effective-the site does not have local fibrinolysis
30Risk assessment, continued Moderate / High risk surgeriesVital organs are involved, with deep or extensive dissectionThe site is associated with local fibrinolysis (eg, prostatic surgery, tonsillectomy, oral or nasal surgery)Local hemostatic measures are ineffective (eg, closed liver or kidney biopsy)The surgical procedure or the underlying condition is expected to induce a hemostatic defect (eg, cardiopulmonary bypass, brain injury, extensive malignancy)Bleeding complications are frequent and/or are likely to compromise the surgical result
31Pre-op workupFor low risk surgeries : if the history and physical exam do not suggest bleeding then no more tests are neededFor high risk surgeries : Hx , Physical , platelet count, PT and PTT must be doneIf Hx/ PE or Coags suggest high risk bleeding then more sophisticated tests should be obtained ( heme consult would not hurt)A “ Bleeding Time “ is NOT warranted pre-op because it does not predict severity of bleeding
32Patients already on anticoagulation Patients might be on prophylactic or treatment anticoagulation preoperativelyFactors to consider when evaluating risk of bleeding with surgery: Age, comorbidities, type of surgery, anticoagulant regimen/ duration and degree of monitoring
33Venous Thromboembolism ( VTE) Temporal relation of VTE to surgery is keyWithin the first month after DVT patients must receive both pre and post-op anticoagulationBetween 2-3 months, pre-op anticoagulation is only needed for high risk patients but post-op anticoagulation is recommended to all patientsAfter 3 months, the risk of bleeding is more than the benefit of anticoagulation so only prophylactic pre and post-op anticoag. is recommended
34Arterial Thromboembolism (ATE) The risk of bleeding is similar pre and post-op in patients with ATEContinue anticoagulation preop for all patientsContinue post-op anticoagulation only if the surgery is minorHigh risk ATE patients (Like anticoagulation for prosthetic valves): a heparin bridge is recommended and restart anticoagulation ASAP post-op
35General Recommendations Always weigh the risk of thrombosis against risk of bleedingPatients on oral AC , allow INR to reach 2 pre-op unless high risk bleeding ( INR< 1.5)Bridge with Heparin if high risk re-thrombosis
37Diabetes- Preoperative Management Why do we care?Increased risk of pre-operative infectionIncreased post-operative cardiovascular morbidity and mortalityFocus is on cardiopulmonary risk assessment and managementHistoryLaboratory Studies
38Diabetes- Preoperative Management HistoryLong term complications of DM (i.e. retinopathy, nephropathy, neuropathy, CHD, PVD)Baseline glycemic control (freq of monitoring, average BS)Hypoglycemia (frequency, severity, awareness, timing)Therapy (pharmacologic and non-pharmacologic)SurgeryMajor vs. Minor surgeryWhen to stop eatingDuration of procedureType of Anesthetic – epidural vs. general
39Diabetes- Preoperative Management Laboratory StudiesBaseline EKG, renal functionBaseline glucose levelsUse this to assess risk for postoperative wound infectionsIn case-control study of post-CABG patients, multivariable analysis found patient with preoperative glucose >200 mg/dL had OR of 10.2 for deep sternal wound infections (independent risk factor)2.
40Diabetes- Preoperative Management Baseline HbA1c – Not recommendedStudy of cardiothoracic surgeries – pt with sternal wound infection had mean HbA1c of 8.44 vs in those without infection but was not statistically significant (p=0.09)3Non-invasive cardiac testing dependent on risk stratificationPreoperative Glycemic Control – GoalsAvoid hyperglycemia and hypoglycemiaNo consensus about how “tight” the control must be (there is data in ICU and post-MI patients not in surgery patients- unsure if this translates)
41Diabetes- Preoperative Management Type 2 – Diet modification onlyCheck BG preoperatively and afterType 2 – Oral agentsDiscontinue agent on morning of surgerySupplemental sliding scale insulinType 1 or 2 – Insulin TherapyFor short procedures, continue SQ regimen1-2 day before, may switch from long-acting to intermediate acting insulinMay reduce night time intermediate insulin if pt has borderline hypoglycemia
42Diabetes- Preoperative Management If in AM and lunch will be eaten- convert as followsOnce daily intermediate in AM 2/3 doseTwice daily ½ total dose as intermediateIf pt misses lunch as well – less AM insulinOnce daily ½ total dose as intermediateTwice daily 1/3 total dose as intermediateMultiple short and intermediate 1/3 total dose as intermediateMultiple short acting 1/3 pre-meal short-actingContinuous insulin continue basal infusion, use SSI prnLater in the day – less AM insulin and start dextrose containing IVFLong, complex surgeries – use IV Insulin (less variability in BG than with SQ regimen), start early in AM, closely monitor electrolytes.No optimal regimen has been found, based on experience and expert opinion.No particular regimen has been found to affect morbidity, mortality, or length of stay.
43Online resources for further info Cardiovascular evaluationPulmonary evaluationManagement of diabetes
44QuizQuestion One:Question: A 76 year-old man with history of CAD s/p CABG (3 years ago), HTN, DM2, CVA, CRI, and newly diagnosed lung mass was sent to the cardiology clinic by the surgeon for “cardiac clearance” for resection of the mass. Patient reports that he had been doing well and in his USOH, and the mass was discovered on a recent CXR. What is the most appropriate recommendation for this pt?A) Pt will need at least a noninvasive test prior to the surgeryB) Pt may proceed with the surgery without further cardiac evaluationC) Pt will need a coronary angiogram prior to the surgeryD) The surgery should be delayed until he is on optimal medical regimenAnswer: B. Pt may proceed with the surgery without further cardiac evaluation. Pt had recent revascularization procedure (within 5 years – CABG 3 years ago), and has not had recurrence of symptoms. Therefore, he can proceed to noncardiac surgery without any further cardiac evaluation. Pt still need to continue medical therapy and postoperative risk stratification and risk factor modification.
45Quiz continued Question Two: Question: As the cardiology consult resident, you are seeing a 72 year-old woman with history of DM2, COPD, and on-going tobacco abuse who was admitted with a fractured pelvis after a fall at home. The patient is a resident at an ALF and fell when she tripped over some furniture. She reports that she has had some difficulty with worsening fatigue and DOE, and she can barely walk across the room because of her symptoms. What is the most appropriate recommendation for this pt awaiting an orthopedic procedure?A) Pt will need at least a noninvasive test prior to the surgeryB) Pt may proceed with the surgery without further cardiac evaluationC) Pt will need a coronary angiogram prior to the surgeryD) The surgery should be delayed until she is on optimal medical regimen and has stopped smokingAnswer: A. Pt should have at least a noninvasive cardiac evaluation given that she has at least one intermediate clinical predictor (DM) and poor functional capacity (METS<4). If low risk on the noninvasive test, then she may proceed to the OR; but if high risk, she may need more invasive testing such as coronary angiography.
46Quiz continued Question Three: You are asked to evaluate Mr. L, a 65 year old male with known COPD, in pre-op clinic preceding planned resection for a 2 cm right upper lobe nodule. Which of the following statements is FALSE:A) If Mr. L’s FEV1 is 40% predicted, he should undergo quantitative V/Q scanning and possibly exercise testing prior to surgeryB) If Mr. L’s FEV1 is 50% predicted, he can proceed to surgery without further testing so long as lobectomy is not plannedC) If Mr. L’s FEV1 is 90% predicted with a normal DLCO and MVV, he can proceed to surgery including lobectomy without further testingD) If Mr. L’s FEV1 is 2.2L, but his DLCO is only 40% predicted, he should undergo further testing prior to surgeryAnswer: B – If Mr. L has an FEV1 of 50% predicted, he shouldn’t go directly to surgery – instead, he should undergo quantitative V/Q testing and possibly exercise testing prior to surgery for further risk stratification
47Quiz continued Question Four: Question: Which of the following is NOT a significant risk factor for the development of postoperative pneumonia, based on the VA study outlined above?A) Thoracic surgeryB) Age greater than 70C) History of inhaler useD) Receipt of general anesthesiaAnswer: C – there is no evidence that a history of inhaler use is directly related to risk for post-op PNA, although COPD has been shown to be a risk factor in various smaller studies.
48Question Five: Quiz continued Question: Mr Green is a 69 yo healthy male scheduled to have CABG in 2 weeks. You are asked to asses his bleeding risk. How would you asses him?A) History aloneB) History and physical examC) PT/PTT/plateletsD) All of the aboveAnswer: D. CABG is a high-risk surgery, so he will need a thorough evaluation prior to the procedure.
49Question Six: Quiz continued Question: Mr. Smith is a 68 year old male on Coumadin for a prosthetic mitral valve. He is scheduled to have an inguinal hernia repair. How would you manage his coumadin pre/post-op?A) Stop Coumadin 3 days pre-op, no need for bridge. Restart Coumadin 3 days post-opB) Stop Coumadin 3 days preop, bridge with heparin when INR<2.5, restart heparin ASAP post-op, and then restart CoumadinC) Continue Coumadin through surgeryD) Stop Coumadin one day prior to surgery and do not resume until 1-2 weeks post-opAnswer: B. This patient is at high risk for ATE despite the low-risk nature of the surgery and needs a heparin bridge for his procedure.
50Question Seven:Question: Ms. Apple is a 28 year old female undergoing thyroidectomy in one week. Pre-op labs show a PTT of 68, INR of 1.1, and a normal CBC. She give no history of abnormal bruising or bleeding. Your next step is:A) Proceed with surgeryB) Consult hematology for further workupC) Proceed with surgery after 4 units FFPD) Proceed with surgery after 5 mg of Vitamin K SQ x1Answer: B. This patient has a high-risk surgery (head and neck) and therefore needs further workup (i.e. mixing study, etc.).
51Question Eight:Question: What aspect of history, physical or laboratory studies is associated with increased risk of post-operative wound infections?A) Baseline hemoglobin A1cB) History of retinopathyC) Preoperative glucose levelD) Use of insulinAnswer: Preoperative blood glucose > 200 has been associated with increased risk of deep sternal wound infections in post-CABG patients (found to have OR of 10.2).
52References Cardiovascular evaluation: Pulmonary evaluation: ACC/AHA Guideline on Perioperative Cardiovascular Evaluation for Noncardiac Surgery,Pulmonary evaluation:Arozullah AM, Khuri SF, Henderson WG et al. Development and validation of a multifactorial risk index for predicting postoperative pneumonia after major noncardiac surgery. Ann Intern Med 2001;135:Beckles MA, Spiro SG, Colice GL et al. The physiologic evaluation of patients with lung cancer being considered for lung resectional surgery. Chest 2003;123:105S-114SBrooks-Brunn JA. Predictors of postoperative pulmonary complications following abdominal surgery. Chest 1997;111:564-71Brooks-Brunn JA. Postoperative atelectasis and pneumonia. Heart Lung 1995;24:94-115Datta D, Lahiri B. Preoperative evaluation of patients undergoing lung resection surgery. Chest 2003;123:Garibaldi RA, Britt MR, Coleman ML et al. Risk factors for postoperative pneumonia. Am J Med 1981;70:677-80Wyser C, Stulz P, Soler M et al. Prospective evaluation of an algorithm for the functional assessment of lung resection candidates. Am J Respir Crit Care Med 1999;159:1450-6
53References Anticoagulation: Diabetes: The clinical impact of increased sensitivity PT and APTT coagulation assays. Am J Clin Pathol 1999; 112:225.Williams' Hematology. Beutler, E, Lichtman, MA, Coller, BS, et al (eds). McGraw-Hill, New York, 6th edition, 2001; p. 1471Outcomes of patients with no laboratory assessment before anesthesia and a surgical procedure. Mayo Clin Proc 1997; 72:505Usefulness of preoperative laboratory assessment of patients undergoing elective herniorrhaphy. Arch Surg 1992; 127:801Management of anticoagulation before and after elective surgery. N Engl J Med 1997; 336:1506Diabetes:1. Khan NA, Ghali WA. Perioperative management of diabetes mellitus. In: UpToDate, Rose, BD (Ed), UpToDate, Waltham, MA, 2005.2. Trick WE, et al. Modifiable risk factors associated with deep sternal site infection after coronary artery bypass grafting. J Thorac Cardiovasc Surg 2000 Jan;119(1):3. Latham R, et al. The association of diabetes and glucose control with surgical-site infections among cardiothoracic surgery patients. Infect Control Hosp Epidemiol 2001 Oct;22(10):