Transcript LECTURE1-Role of anaesthetist in the preoperative care prof

Lecture Title: Role of anesthesiologist
in pre-operative period
Lecturer name:
Lecture Date:
Lecture Objectives..
Students at the end of the lecture will be
able to:
1) learn pre-anesthetic patient evaluation and risk stratification.
2) Obtain a full history and physical examination including allergies, current
medications, past anesthetic history, family anesthetic history
3) The medical student will understand how patient co-morbidities can affect the
anesthetic plan.
4) The medical student will be able to understand potential anesthetic options for a
given surgical procedure.
5) The medical student will be able to plan an anesthetic for a basic surgical
procedure.
6) The student will understand risk stratification of a patient undergoing anesthesia.
Stages of the Peri-Operative Period
Pre-Operative
• From time of decision
to have surgery until
admitted into the OR
theatre.
Stages of the Peri-Operative Period
Intra-Operative
• Time from entering the
OR theatre to entering
the Recovering Room or
Post Anesthetic Care
Unit (PACU)
Stages of the Peri-Operative Period
Post-Operative
• Time from leaving the
RR or PACU until time of
follow-up evaluation
(often as out-patient)
Preoperative visit.
• To educate about anesthesia , perioperative
care and pain management to reduce anxiety.
• To obtain patient's medical history and
physical examination .
• To determine which lab test or further medical
consultation are needed .
• To choose care plan guided by patient's choice
and risk factors
• Benefits from surgery ←→ Risk of
complications
Preoperative Evaluation:
• A thorough history and physical exam.
• Complete review of systems.
– Organ specific issues.
– Functional Status.
– Habits (smoking, alcohol, drugs).
• Medications (herbals) and allergies.
• Anesthesia history.
• Pre-op labs: one size does not fit all.
Patient related risk factors
(pulmonary)
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Age
Obesity
Smoking
General health status
Chronic obstructive pulmonary disease (COPD)
Asthma
Smoking
• Important risk factor
• Smoking history of 40 pack years or more →↑risk of
pulmonary complications
• stopped smoking < 2 months : stopped for > 2
months 4:1(57% : 14.5%)
• quit smoking > 6 months : never smoked = 1:1
(11.9% : 11%)
Risk Stratification
• Revised Cardiac Risk Index
– High risk surgery (vascular, thoracic)
– Ischemic heart disease
– Congestive heart failure
– Cerebrovascular disease
– Insulin therapy for diabetes
– Creatinine >2.0mg/dL
Active Cardiac Conditions
• Unstable coronary syndromes
– Unstable or severe angina
– Recent MI
• Decompensated HF
• Significant arrhythmias
• Severe valvular disease
Minor Cardiac Predictors
• Advanced age (>70)
• Abnormal ECG
– LV hypertrophy
– LBBB
– ST-T abnormalities
– Rhythm other than sinus
• Uncontrolled systemic hypertension
Surgical Risk Stratification
• High Risk
– Vascular (aortic and major vascular)
• Intermediate Risk
– Intraperitoneal and intrathoracic, carotid, head
and neck, orthopedic, prostate
• Low Risk
– Endoscopic, superficial procedures, cataract,
breast, ambulatory surgery
Risk Stratification
• ASA physical status
– ASA 1 – Healthy patient without organic
biochemical or psychiatric disease.
– ASA 2- A Patient with mild systemic disease. No
significant impact on daily activity. Unlikely
impact on anesthesia and surgery.
– ASA 3- Significant or severe systemic disease that
limits normal activity. Significant impact on daily
activity. Likely impact on anesthesia and surgery.
Risk Stratification
• ASA 4- Severe disease that is a constant threat
to life or requires intensive therapy. Serious
limitation of daily activity.
• ASA 5- Moribund patient who is equally likely
to die in the next 24 hours with or without
surgery.
• ASA 6- Brain-dead organ donor
• “E” – added to the classifications indicates
emergency surgery.
Step #1:Is the surgery emergent?
Is the surgery emergent?
yes
Operating room*
no
(Next Step)
Consider beta-blockade, pain control
and other peri-operative management
Step 2: Determine Presence of Active
Cardiac Conditions
• If none are present, proceed with surgery
• Presence of one of these delays surgery for
evaluation
• Many patients need a cardiac cath
Step 2
• Unstable coronary syndromes
• Decompensated heart failure
• Significant arrhythmias
• Severe valvular disease
Step #2: Active Cardiac Conditions
Active Cardiac conditions
yes
Evaluate and treat per
current guidelines
no
(Next Step)
Consider Operating Room
Step 3: Surgery Low Risk?
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Low risk surgery includes:
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Endoscopic procedures
Superficial procedures
Cataract surgery
Breast surgery
Ambulatory surgery
Cardiac risk <1%
Testing does not change management
Step #3: Surgery Low Risk?
Low risk surgery
No
(Next Step)
yes
Operating room
The Nervous System
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Problems may be central or peripheral
Thorough history is essential
Correlate history with physical finding
Sources of Problems
Ischemia , Vasospasm, Embolism Thrombosis
Tumor ,Aneurysm , Hemorrhage ,Seizures, Stroke
5. Signs and Symptoms : Nausea / Vomiting
Vertigo, Headache , Visual problems , Sensory abnormalities
Motor weakness
Renal System
Acute / Chronic Renal Failure
– Total
body disease
– Electrolyte abnormalities
– Coagulation disorders
– Hypervolemic, hypertensive,
hyperkalemic
Gastrointestinal System
• Gastric reflux
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Get accurate history
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Evaluate risk of aspiration
Consider gastric prep
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Proton inhibiter or H2 blockers (ranitidine )
Metoclopramide
Antacid
• Gastric reflux
Rapid sequence induction , Cricoid pressure
Endocrine System
Diabetes Mellitus
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Type I -- Insulin dependent
• End organ disease is common
hypertension , coronary artery disease, neuropathy,
retinopathy, nephropathy, autonomic dysfunction
Type II -- Non-insulin dependent
• Onset usually after pregnancy or excessive weight gain
• controlled with diet and exercise
Endocrine System (con’t)
Diabetes Mellitus
– Goals
of Management
– Maintain glucose in 100-250 range
– Provide adequate fluid volume
– Individualize care plan
Endocrine System (con’t)
Pheochromocytoma
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Tumor of chromaffin tissue
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Increased production and release of epinephrine and
norepinephrine
Signs and symptoms
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Intermittent hypertension
Headache
Sweating
Tachycardia
Endocrine System (con’t)
Pheochromocytoma (con’t)
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Secondary problems
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Hyperglycemia
Myocarditis
Cardiomyopathy
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M.I. with CHF
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Intracerebral hemorrhage or heart
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Hematologic System
Anemia
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3 key questions
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What is the cause?
Is it acute or chronic?
Will the patient benefit from delay?
Acute blood loss poorly tolerated
Chronic renal failure
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Anemia and platelet dysfunction
Tolerate anemia well
Platelet dysfunction corrected with dialysis
Hematologic System (con’t)
Disorder of hemostasis
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Congenital
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Hemophilia
Acquired
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Thrombocytopenia
Hepatic dysfunction
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Platelet dysfunction
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Drugs induce
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Airway Evaluation
 Take very seriously history
of prior difficulty
 Head and neck movement
(extension)
◦ Alignment of oral, pharyngeal,
laryngeal axes
◦ Cervical spine arthritis or
trauma, burn, radiation, tumor,
infection, scleroderma, short
and thick neck
Airway Evaluation
• Jaw Movement
– Both inter-incisor gap and
anterior subluxation
– <3.5cm inter-incisor gap
concerning
– Inability to sublux lower
incisors beyond upper
incisors
• Receding mandible
• Protruding Maxillary
Incisors (buck teeth)
Airway Evaluation
• Oropharyngeal visualization
• Mallampati Score
• Sitting position, protrude tongue, don’t say “AHH”
Preoperative Testing
• Routine preoperative testing should not be
ordered.
• Preoperative testing should be performed on
a selective basis for purposes of guiding or
optimizing perioperative management.
Preoperative Testing5
• Procedure based.
– Low risk
• Baseline creatinine if procedure involves contrast dye.
– Intermediate risk
• Base line creatinine if contrast dye or >55yr of age.
– High risk
• CBC, lytes & S, creatinine as above.
• PFTs for lung reduction surgery.
Preoperative Testing
• Disease-based indications
– Alcohol abuse
• CBC, ECG, lytes, LFTs, PT
– Anemia
• CBC
– Bleeding disorder
• CBC, LFTs, PT, PTT
– Cardiovascular
• CBC, creatinine, CXR, ECG, lytes
Preoperative Testing
• Disease-based indications
– Cerebrovascular disease
• Creatinine, glucose, ECG
– Diabetes
• Creatinine, electrolytes, glucose, ECG
– Hepatic disease
• CBC, creatinine, lytes, LFTs, PT
– Malignancy
• CBC, CXR
Preoperative Testing
• Disease-based indications
– Pregnancy (controversial)
• Serum B-hCG- 7 days, Upreg 3 days
– Pulmonary disease
• CBC, ECG, CXR
– Renal disease
• CBC, Cr, lytes, ECG
– RA
• CBC, ECG, CXR, C-spine (atlantoaxial subluxation)
– AP C-spine, AP odontoid view and lateral flexion and
extention.
Preoperative Testing
• Disease-based
– Sleep apnea
• CBC, ECG
– Smoking >40 pack year
• CBC, ECG, CXR
– Systemic Lupus
• Cr, ECG, CXR
Preoperative Testing
• Therapy-based indications
– Radiation therapy
• CBC, ECG, CXR
– Warfarin
• PT
– Digoxin
• Lytes, ECG, Dig level
– Diuretics
• Cr, lytes, ECG
– Steroids
• Glucose, ECG
Informed Consent
1. Frequently questioned in malpractice
cases
2. Risks / benefits
3. Alternatives
4. Answer all questions
5. Do not deceive the patient
Risks of Anesthesia
1. Determine what the patient wants
to know - Do not frighten patients
2. Start with minor risks
3. Proceed to serious risks
ASA Physical Status
1. Risk indicators
2. Developed for statistical studies
3. Used to compare outcomes
ASA Physical Status Classification
• ASA 1 – normal, healthy patient
• ASA 2 – patient with mild, well-controlled systemic
disease
• ASA 3 – patient with severe systemic disease that
limits activity
• ASA 4 –patient with severe, life-threatening
disease
• ASA 5 – moribund patient not expected to survive
for 24 hours with or without surgery
Document the Visit
1.
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4.
Complete the evaluation form
Enter progress notes
Have patient sign consent
Write appropriate orders
Q & A
Reference book and the relevant
page numbers..
Thank You 
Dr.