450 likes | 793 Views
Preoperative Medical Evaluation/Consultation of the Healthy Patient. Greg Rosencrance, MD 2006 Nevada Chapter Scientific Meeting Saturday June 14, 2006 Las Vegas, Nevada. Principles of Consultation. Determine the question Establish the urgency Gather data “look for yourself”
E N D
Preoperative Medical Evaluation/Consultation of the Healthy Patient Greg Rosencrance, MD 2006 Nevada Chapter Scientific Meeting Saturday June 14, 2006 Las Vegas, Nevada
Principles of Consultation • Determine the question • Establish the urgency • Gather data “look for yourself” • Communicate briefly • Make specific recommendations • Understanding of the role • Communicate directly • Provide appropriate follow-up
Compliance with Recommendations • Improves with Brevity • Predictors • Severity of illness • Type and number < 5 • Best with medications • Worst with those requiring action • Interaction with requesting physician
Following of Patients • Patients should be followed through the postoperative period. Perioperative MI’s peak at the 3rd to 5th days.
Clearance • You are not “clearing” the patient for surgery • Seek factors that may put the patient at higher than average risk and try to reduce these • Risks are specific to the individual patient, type of procedure, type of anesthesia • Average Risk
Anesthesia Effects • JAMA 1988, 100,000 procedures • patient and surgical risk factors were more important than anesthesia factors • duration • experience of operator • inhalation techniques JAMA 1988;260:2859
ASA or Dripps • Considers mortality based on the general clinical impression • Diagnose the severity of systemic illness • Reproducible despite broadly defined categories
ASA Criteria American Society of Anesthesiologists Classification of Preoperative Risk* ASASystemic disturbanceMortality 1 Healthy patient with no disease <0.03 percent outside of the surgical process 2 Mild to moderate systemic disease 0.2 percent caused by the surgical condition or by other pathological processes 3 Severe disease process which 1.2 percent limits activity but is not incapacitating
ASA Criteria ASASystemic disturbance Mortality 4 Severe incapacitating disease process 8 percent that is constant threat to life 5 Moribund patient not expected to survive 34 percent 24 hours with or without an operation E Suffix to indication emergency surgery Increased for any class * Adapted from Cohen, MM, Duncan, PG, Tate, RB, JAMA 1988; 260:2859
Anesthetic Risk • Stress Responses • Adverse and Idiosyncratic Reactions • eg malignant hyperthermia and hepatitis • Organ system effects • myocardial depressants (preload dependent) • dehydration • autonomic neuropathies
Anesthetic Risk • Effects of inhalational anesthesia • decrease in FRC with atelectasis and V/Q mismatch • loss of sighs • decreased mucociliary clearance
Type of Anesthesia • No difference in cardiac or overall perioperative mortality between general or spinal anesthesia • Lower risk with minor regional anesthesia • Since the type of anesthesia does not influence mortality, the medical consultant should not recommend a particular anesthetic technique
Clinical Evaluation Preoperative Patient Questionnaire† • Do you feel unwell? • Have you ever had any serious illnesses in the past? • Do you get any more short of breath with exertion than other people of your age? • Do you have any coughing? • Do you have any wheezing ? • Do you have any ankle swelling? • Have you taken any medicine or pills in the last three months (including excess alcohol)?
Clinical Evaluation (continued) Preoperative Patient Questionnaire* • Have you any allergies? • Have you had an anesthetic in the last two months? • Have you or your relatives had any problems with a previous anesthetic? • Observation of serious abnormality from “end of bed” which might affect anesthetic ? • What is the date of your last menstrual period? *Adapted from Wilson, ME, Williams, MB, Baskett, PJ, et al, BR Med J 1980; 1:509
Exercise Capacity • Ask all patients • Two Blocks on level ground or carrying two bags of groceries up one flight of stairs without symptoms = 4 METS • Average cardiac risk if they can perform these
Age • Increased Risk with Increased Age • 50,000 elderly patients (elective) • Under 60, 1.3% mortality • 80-89, 11.3% mortality Ann Intern Med 2001;134:637
Age • 795 patients over 90 • 80% ASA 3 or higher • Survival at 2 years no different than controls • Age alone should not be used as the sole criterion to withhold surgery Ann Intern Med 2001;134:637
Laboratory Evaluation • 2000 pts undergoing elective surgery • 60% would not have been performed if testing had been done for recognizable indications • 0.22% revealed abnormalities that might influence perioperative management • May increase medicolegal risk JAMA 1985;253:3576
Laboratory Evaluation Probability of an Abnormal Screening Test Result
Laboratory Evaluation Predictive Value of Positive Test Results
Laboratory Evaluation • Probably safe to use labs that were performed and normal within the past 4 months unless a change in the clinical status • 7549 preop tests in 1109 patients • 47% duplicates within the prior year • 461 abnormal 78 (17%) of repeat values were outside accepted norms Ann Intern Med 1990;113:969
Laboratory Evaluation • CBC • Anemia in 1% of asymptomatic patients • Use as a baseline in patients expected to have significant blood loss • No evidence to support baseline testing of WBC or Platelets JAMA 1985;253:3576
Laboratory • Electrolytes • 0.6% frequency of abnormality • relationship between operative morbidity is unclear • Routine determinations are not recommended JAMA 1985;253:3576
Laboratory • Renal Function • 0.2% prevalence of elevated creatinine if asymptomatic and no renal history • prevalence increases with age • 46-60 9.8% prevalence • Renal Insufficiency is associated with increased surgical morbidity • reasonable to obtain Cr if > 50
Laboratory • Glucose • Abnormalities increase with age • 25% of patients > 60 have an increase • operative risk and diabetes • vascular or CABG • Routine not rec prior to elective surgery • Exceptions obese,steroids,FH
Laboratory • LFT’s • 0.3% of asymptomatic patients • severe abnormalities increase morbidity • not clear if mild abnormalities are similar • Routine testing not recommended
Laboratory • Hemostasis • Routine testing is not indicated • Restrict to those with a known bleeding diathesis
Laboratory • Urinalysis • Relationship between asymptomatic urinary tract infections and surgical infection is unclear • 4.58 wound infections in nonprosthetic knee operations may be prevented by the use of routine urinalysis. • $1.5 million per wound infection prevented
Laboratory • EKG • Abnormalities increase with age • Unsuspected arrhythmias • other than sinus, >5 PVC’s, PAC’s increases risk of perioperative cardiac events • BBB does not increase the risk of cardiac complications following non cardiac sugery
Laboratory • Electrocardiogram • Unrecognized myocardial infarctions are relatively common • Framingham study • 5127 participants, 708 MI’s, 25% were identified only via routine EKG • Proportion of unrecognized infarcts higher in women and older men
EKG Guidelines • Men > 40 • Women > 50 • Known cardiac disease • Clinical Evaluation suggesting the possibility of cardiac disease • Patients at risk for electrolyte abnormalities
EKG Guidelines • DM, HTN • Major Surgical Procedures
Chest X-Ray • Add little • 905 surgical admissions • screened for risk factors for abnormal preop CXR, • age>60, clinical findings c/w cardiac or pulmonary disease • no risk factors in 368, 1 (0.3%) had an abnormal cxr which did not affect surgery
Chest X-Ray • 504 had identifiable risk factors • 114 (22%) had significant abnormalities • Meta analysis 21 studies • 14,390 routine cxr • 1444 abnormal, 140 unexpected, 14 ( 0.1%) influenced management • CXR not routinely performed unless > 60, or suspected cardiac or pulmonary disease
Pulmonary Function Tests • Not routinely recommended for healthy patients • ACP recs: • lung resection surgery, CABG, upper abdominal surgery w/tobacco history, head and neck or orthopedic surgery w/ uncharacterized pulmonary disease
Summary • Screening questionnaire for all patients • History of exercise tolerance for all • BP and pulse for all • H&P if one of the above is abnormal, > 60, or major surgery • Pregnancy test for women who may be pregnant • Hg if suspected major blood loss
Summary • Creatinine if hypotension is suspected, nephrotoxic drugs, > 50 • EKG unless within 1 month criteria as stated • CXR if > 60, suspected disease unless within 6 months • PFT’s per ACP position statement • All other tests only if clinical evaluation suggests a likelihood of disease