Transcript Preoperative Evaluation and Management

Preoperative Evaluation
and Management with Cardiac
Evaluation
Lauren Hojdila, MSA, AA-C
Nova Southeastern University
The Preoperative Evaluation
A Standard of Care
• The Joint Commission for the Accreditation
of Healthcare Organizations (TJC) requires
that all patients receive a preoperative
anesthetic evaluation
• The American Society of Anesthesiologists
(ASA) has approved Basic Standards for PreAnesthetic Care, which outlines the
minimum requirements for a preoperative
evaluation
Goals of the
Preoperative Evaluation
• Primary Goals
– Reduce patient risk
– Reduction of perioperative morbidity and
mortality
• Secondary Goals
– Promote efficiency
– Reduce costs
*Conducting a preoperative evaluation is
based on the premise that it will modify
patient care and improve outcome.
Does the Preoperative Evaluation alter
Patient Care ?
• Gibby et al found that anesthetic plans
were altered in 20% of all patients due to
conditions identified at the preoperative
evaluation
• The most common conditions resulting in
modification of the anesthetic plan were
gastric reflux, IDDM, asthma, and
suspected difficult airway
• These findings indicate the need to do the
initial preoperative evaluation before the
day of surgery
Components of the
Preoperative Evaluation
• Personal Interview
• Review of systems
• Prior anesthetic experience (Difficult intubation, delayed
emergence, MH, delayed NMB, PONV)
• Drug allergies
• Physical Examination
• Airway exam
• Body habitus
• Review of Medical Records
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Medications
Substance use (alcohol, tobacco, illicit)
Surgical history
Surgical Diagnosis (Organ systems involved, Planned procedure)
ASA Classification
Class 1:
Healthy patient, No medical problems
Class 2:
Mild systemic disease
Class 3:
Severe systemic disease, but not incapacitating
Class 4:
Severe systemic disease that is a constant threat to life
Class 5:
Moribund, not expected to live 24 hours irrespective of operation
Class 6:
Organ donor
E may be added to the status number to designate an emergency operation
Thyromental Distance
Airway Examination
• Distance from the thyroid cartilage to the
inside of the mentum
• Measured with the neck in the sniff
position
• What is normal thyromental distance?
A higher Mallampati class combined with a mental distance <2 finger-breadths
may better predict increased difficulty with intubation.
Mallampati Classification
Airway Examination
• Class I:
Soft palate, fauces, uvula, tonsillar pillars
• Class II:
Soft palate, fauces, uvula
• Class III:
Soft palate, base of uvula
• Class IV:
Hard palate only
What other feature increase the likelihood
of difficult intubation?
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Short, thick neck (Neck circumference)
Diminished neck extension
Decreased tissue compliance
Large tongue
Teeth (Overbite, Large teeth)
Decreased TMJ mobility
NPO Guidelines
• Healthy Adults (No risk factors)
• No solid foods for a minimum of 6 hours
• Clear liquids up to 2 hours prior to elective case
• Oral medications up to 1-2 hours with sip of water
• Pediatric patients
• Clear liquids up to 2 hours preOp
• Breast milk up to 4 hours preOp
• Solid foods, nonhuman milk, formula up to 6
hours preOp
Aspiration
Who has a higher risk ?
Gastrointestinal Obstruction
GERD
Diabetes mellitus
Recent solid-food intake
Abdominal distention
Pregnancy
Depressed consciousness
Recent opioid administration
Upper GI or naso-oropharyngeal bleeding, with or
without trauma
• Emergency surgery
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The Healthy Patient
Systems Approach
• Airway
• Examination as previously described
• Pulmonary
• History – Tobacco use, asthma, SOB/DOE, sleep apnea, wheezing,
cough, etc.
• Physical exam – Lung sounds, chest excursion, use of accessory
muscles, cyanosis, clubbing, etc.
• Cardiovascular
• HTN, CAD, MI, angina, CHF, dysrhythmias, valvular dx, heart
sounds, carotid bruits, peripheral pulses
• Neurologic
• Mental status, h/o seizures, neuromuscular disease, nerve injury
• Endocrine
• Diabetes mellitus, thyroid disease, adrenal cortical suppression, etc.
The Patient with Known
Cardiac Disease
• Define risk
– Goldman risk index (Independent predictors)
• High-risk surgery, h/o ischemic heart dx, h/o
CHF, h/o cerebrovascular dx, preOp insulin
therapy, and preOp serum creatinine > 2 mg/dL
• Need for further testing
• Recent MI or ECG changes
• Poor exercise tolerance
• Need for cardiac surgery
• Prior to current elective surgery
The Patient with
Pulmonary Disease
• Site and Type of Surgery
• Thoracic and upper abdominal procedures are associated
with increased pulmonary complications
• Type and Severity of Disease
• Does the disease have a reversible component ?
• When were they last hospitalized ?
• Interview
• Exercise tolerance, chronic cough, smoking history
• What are their current treatment modalities?
• Physical Exam
• Lungs sounds – wheezing, rhonchi, decreased breath sounds
Other Diseases of Concern
• Diabetic Mellitus
• Increased risk of CAD, perioperative MI, hypertension, and
CHF
• Consider beta-blockade in diabetics with CAD to help limit
myocardial ischemia
• Renal Disease
• Altered drug metabolism
• Fluid management
• Liver Disease
• Coagulation abnormalities
• Altered protein binding and volume of distribution
Perioperative
Lab Testing
• No evidence supports the use of routine laboratory
testing
• There is support for the use of selected lab analysis based on the
patient’s preOp history, physical exam, and proposed surgical
procedure
• A positive result is frequently a false-positive
• High incidence of false-positives when performing tests in normal
patients (a population with a very low prevalence of disease)
• Risk/Cost vs. Benefit
• Medical testing is associated with significant cost
• The risk of intervention may outweigh the benefit
• Is it going to change what you do ???
Recommended
Lab Tests
• CBC / Hemoglobin
• Hgb of 7 g/dL is acceptable in patients without systemic
disease (depending upon proposed surgical procedure)
• In patients with systemic disease, signs of inadequate
systemic oxygen delivery are an indication for transfusion
• Electrolytes
• Creatinine and glucose in older asymptomatic adults
• BUN and creatinine in patients with systemic disease or on
medications that affect the kidneys
• Coagulation Studies
• Recommended in patients with bleeding disorders, liver
dysfunction, or on anticoagulant therapy
Recommended Lab Tests
Continued
• Pregnancy Testing
• Current practice:
– testing all females of child-bearing age
• Chest X-rays
• Routine testing in the population without risk
factors can lead to more harm than good
• Is indicated in patients with a history or clinical
evidence of active pulmonary disease, and may be
indicated routinely in patients of advanced age
Preoperative Medications
• What is the goal of premedication ?
• Anxiolysis, Sedation, Amnesia, Analgesia, etc.
• What drug, when, and how much ?
• Several classes of drugs may be available to facilitate the
desired goal
• Timing of drug delivery is as important as drug selection
• There is no BEST drug or combination of
drugs for preoperative medication
• The specific drugs selected are based on the goals of
premedication balanced with the potential side effects these
drugs may produce
Preoperative Medications
• Benzodiazepines
• Act on GABA receptors to produce selective
anxiolysis at doses that do not produce excessive
sedation, depression of ventilation, or adverse
cardiac effects
• Note: May lead to any of the above when given
with opioids
• Opioids
• Should be used when there is a need to provide
analgesia
Preoperative Medications
Continued
• Antiemetics
• Administered in the preOp or intraOp period as prophylaxis
against PONV
• Droperidol (Black-Boxed), Reglan (? Antiemetic), 5HT3
inhibitors, Decadron, Scopolamine patch (apply several
hours before induction of anesthesia)
• Drugs used to alter gastric volume/pH
• Clinically significant pulmonary aspiration of gastric fluid is
rare in healthy patients undergoing elective surgery,
maintenance of a patent airway is more important than
routine pharmacologic prophylaxis
• Use in patients with specific indications
What has changed about your plan?
• Airway
• Medications
• Trends of Vital Signs
Pre-Operative Cardiac
Evaluation
Cardiovascular Disease
• During a lifetime, a heart contracts more
than 4 billion times
– To support the active cardiac state, the heart
supplies more than 4 million liters of blood to
the myocardium and more than 200 million
liters to the systemic circulation
• Cardiac output can vary from 3 L/min to
30 L/min depending on activity level
– Regional blood flow can vary up to 200%
Cardiovascular Disease
Major Disease Categories
• Coronary heart disease (CHD/CAD)
• Hypertension (HTN)
• Rheumatic heart disease (RHD)
• Bacterial endocarditis
• Congenital heart disease
Coronary Heart Disease
• Leading cause of death in the United
States
• Around 1 million deaths per year from
cardiovascular pathology
• About ½ of these related to ischemic disease
• No. 1 cause of death among women in the
U.S.
• Lifetime risk of death from CHD: 31%
• Lifetime risk of death from breast CA: 2.8%
Coronary Heart Disease
Risk Factors
• Past medical history
• Chronic disorder
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Hypertension
Hyperlipidemia
Diabetes mellitus
Thyroid dysfunction
• Cardiac surgery
• Rhythm disorder
• Acute rheumatic fever
Coronary Heart Disease
Risk Factors: Family History
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Diabetes mellitus
Heart disease
Hypertension
Congenital heart defects
– Particularly VSD
• Sudden death
• Early age cardiovascular disease
Coronary Heart Disease
Risk Factors: Social History
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Stressful or physical work
Tobacco use
Poor nutritional status
“High strung” personality
Lack of relaxing activities
Use of alcohol
Use of illegal drugs
Preoperative Clinical Evaluation
 Identification of serious cardiac disorder
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 CAD, CHF, Arrhythmias
 Initial history, Physical examination, ECG
Define disease severity, stability, and prior treatment
Functional capacity
Age
Comorbidities
 DM, peripheral vascular disease, renal dysfunction, chronic pulmonary
disease
 Type of surgery
 Consider higher risk
 Vascular procedures
 Prolonged complicated thoracic, abdominal and head and neck
procedures
Hypertension
Management of Preoperative Cardiovascular Conditions
• Severe Htn(DBP >110mmHg) should be
controlled before surgery when possible
• Continuation of preoperative
antihypertensive treatment is critical to
avoid severe postoperative hypertension.
• Consider the urgency of surgery and the
potential benefit of more intensive
medical therapy.
Valvular Heart Disease
Management of Preoperative Cardiovascular Conditions
• Symptomatic stenotic lesions (MS or AS):
associated with risk of perioperative severe
CHF or shock and often require
percutaneous valvotomy or replacement to
lower cardiac risk.
• Symptomatic regurgitant lesions (AR or MR):
usually better tolerated perioperatively and
may be stabilized before surgery with
intensive medical therapy and monitoring
Myocardial Heart Disease
Management of Preoperative Cardiovascular Conditions
• Dilated and hypertrophic cardiomyopathy
are associated with an increased incidence
of perioperative CHF.
• Maximizing preoperative hemodynamic
status and providing intensive
postoperative medical therapy and
surveillance.
Arrhythmias and Conduction Abnormalities
Management of Preoperative Cardiovascular Conditions
• Careful evaluation for underlying
cardiopulmonary disease, drug toxicity, or
metabolic abnormality.
• Therapy: reverse any underlying cause
and treat the arrhythmia
Medical Therapy for
Coronary Artery Disease
• If patients require β-blockers, calcium
channel blockers, or nitrates before
surgery, continue them into the operative
and post-op period.
• The same is true for therapies used to
control CHF
• β-blockers reduce postoperative ischemia
– Protection against ischemia may also reduce
risk of MI
Cardiac Evaluation
• Clinical predictors
• Functional capacity
• Surgical risk
• Non-invasive testing
• Invasive testing
Method of Assessing Cardiac Risk
• Resting Left Ventricular Function
• Exercise Stress Testing
• Pharmacological Stress Testing
• Ambulatory EKG monitoring
• Coronary Angiography
Clinical Predictors of Increased
Perioperative Cardiovascular Risk
(Myocardial Infarction, Congestive Heart Failure, Death)
• Minor
Advanced age
Abnormal EKG(LVH, LBBB, ST-T abnormalities)
Rhythm other than sinus (eg, atrial fibrillation)
Low functional capacity (eg, unstable to climb one flight of stairs with a bag of
groceries)
History of stroke
Uncontrolled systemic hypertension
• Intermediate
Mild angina pectoris(Canadian Cardiovascular Society Class I or II)
Prior myocardial infarction by history or pathological waves
Compensated or prior CHF
Diabetes mellitus
Clinical Predictors of Increased
Perioperative Cardiovascular Risk
(Myocardial Infarction, Congestive Heart Failure, Death)
• Major
Unstable coronary syndromes
– Recent myocardial infarction with evidence of important
ischemic risk by clinical symptoms or noninvasive study
– Unstable or severe angina
– Decompensated CHF
Significant arrhythmias
– High grade atrioventricular block
– Symptomatic ventricular arrhythmias in the presence of
underlying heart disease
– Supraventricular arrhythmias with uncontrolled ventricular rate
Severe valvular disease
Functional Capacity
1 MET
Can you take care of yourself?
Can you eat, dress, or use the toilet?
Can you walk indoors around the house?
Can you walk a block or two on level ground at 2-3 mph?
Can you do light housework, such as dusting or washing dishes?
4 METs
Can you climb a flight of stairs or walk up a hill?
Can you walk on level ground at 4 mph?
Can you run a short distance?
Can you do heavy housework, such as scrubbing floors or lifting or moving
heavy furniture?
Do you participate in moderate recreational activities, such as golf, bowling,
dancing, doubles tennis, or throwing a baseball or football?
>10 METs
Do you participate in strenuous sports, such as swimming, singles tennis,
football, basketball, or skiing?
Surgical Risk
Low Risk Procedures
• Low surgical risk:
– Endoscopy
– Bronchoscopy
– Cystoscopy
– Dermatologic procedures
– Breast biopsy
– Opthalmologic procedures
Surgical Risk
• Intermediate surgical risk:
– Orthopedic surgery
– Urologic surgery
– Uncomplicated abdominal surgery
– Uncomplicated head and neck
Surgical Risk
• High surgical risk:
– Emergency surgery
– Cardiac procedures
– Aortic or vascular surgery
– Anticipated prolonged surgery
• Large fluid shifts or blood loss
• Ex: Whipple, spinal surgery
Electrocardiogram
Significant ECG Findings
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Past myocardial infarction
Left bundle branch block
Bifasicular block
Atrioventricular block
– Mobitz-Type II or 3°AVB
• Prolonged QT interval
• Right ventricular hypertrophy
Echocardiography
• Displays 2-dimensional ultrasound images of
the heart
• Can be used to produce accurate assessment
of the velocity of blood and cardiac tissue
– Utilizes pulse wave Doppler ultrasound
• Diagnostic uses:
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Wall motion abnormalities
Valvular dysfunction (valve area and function)
Septal defects
Calculation of cardiac output and ejection
fraction
Echocardiography
Types of Echocardiography
• Transthoracic (TTE)
• Exercise stress echo
• Dobutamine stress echo
• Transesophageal (TEE)
Stress Testing
• Used to evaluate myocardial perfusion
during stress as compared to at rest
• Diagnostic usefulness debatable!
• Types of evaluation:
– Exercise (a.k.a. treadmill)
– Dobutamine or adenosine
– Radiotracer
• Tc99m Sestamibi (Cardiolite®)
• Thallium
Cardiac Catheterization
• Invasive angiography of myocardial
perfusion
• Diagnostic usefulness:
– Arterial occlusion
– Thrombotic lesions
– Aneurysmal enlargement
• Concurrent procedures:
– Percutaneous transluminal coronary angioplasty
(PTCA)
– Coronary artery stent placement
– Dissection and stroke
Stepwise Approach to Preoperative
Cardiac Assessment
Need for
noncardiac
surgery
emergency
Recent
coronary
evaluation
no
yes
O.R.
no
Urgent or elective
Coronary
revascularization
within 5 yrs
no
Postoperative risk
stratification and
risk factor management
yes
Recurrent
symptoms or
signs
yes
Recent coronary
angiogram or
stress test?
Favorable result and
no change in symptoms
Unfavorable result
and change in symptoms
Clinical
predictors
Major
Intermediate
Minor or No
O.R.
Stepwise Approach to Preoperative
Cardiac Assessment
Minor or no clinical predictors
Poor(<4METs)
Moderate or excellent(>4METs)
High surgical
risk procedure
Intermediate
surgical risk
procedure
Noninvasive testing
High risk
low risk
Consider coronary angiography
Subsequent care by findings
and treatment results
O.R.
Postoperative management
Minor clinical predictors:
•Advanced age
•Abnormal ECG
•Rhythm other than sinus
•Low functional capacity
•History of stroke
•Uncontrolled systemic hypertension
Stepwise Approach to Preoperative
Cardiac Assessment
Intermediate clinical predictors
Poor
(<4METs)
Moderate or excellent
(>4METs)
High surgical
risk procedure
Noninvasive Low risk
testing
Intermediate or low
surgical procedure
O.R.
Low surgical
risk procedure
Postoperative risk stratification
and risk factor reduction
High risk
Consider coronary
angiography
Subsequent care
dictated by findings
and treatment results
Intermediate clinical predictors:
•Mild angina pectoris
•Prior MI
•Compensated or prior CHF
•DM
Stepwise Approach to Preoperative
Cardiac Assessment
Major clinical predictors
Major clinical predictors:
•Unstable coronary syndromes
•Decompensated CHF
•Significant arrhythmias
•Severe valvular disease
Delay or cancel
noncardiac surgery
Coronary
angiography
Medical management
and risk factor modification
Subsequent care
dictated by findings
and treatment results
Summary
• How has the information gained in the
pre-op evaluation changed your plan?
• Is there anything further that you need to
deliver a safe anesthetic?
• Should you proceed with the case?
• Don’t forget to monitor closely.
• Have a back-up plan ready to implement.