This document discusses pre-operative assessment and management of patients by anesthesiologists. It covers goals of pre-op care like reducing risk and costs. The anesthesiologist is responsible for determining medical status, developing an anesthesia plan, and informing the patient. A thorough pre-op evaluation can reduce anxiety as much as medication. The document outlines components of the pre-op evaluation including medical history, physical exam, lab tests, and prescribing pre-op medications. Specific considerations for common comorbidities like diabetes and cardiovascular disease are also reviewed.

1. santosh k dhungana
MD GP JR II

2.  pre-op assessment
 pre-anesthetic prescribing
 induction agents
 muscle relaxants
 reversal
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3. goals
reduce patient risk
reduce morbidity of surgery
promote efficiency
reduce costs
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4. anesthesiologist shall be responsible for
 determining the medical status of the patient
 developing a plan of anesthesia care
 acquainting the patient with the proposed plan
ASA
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5.  study evaluating methods of reducing preoperative
anxiety
 thorough preoperative evaluation can be as effective as
an anxiolytic premedication
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6.  Review available medical records
 Interview and perform focused examination of the patient
 Discuss medical hx, including previous anesthetic experiences and
medical therapy
 Assess those aspects of the patient’s physical condition that might
affect decisions regarding perioperative risk and management.
 Order/ review pertinent available tests and consultations as
necessary for the delivery of anesthesia care
 Order appropriate preoperative medications
 Ensure that consent has been obtained for the anesthesia
care- BRAN (benefit, risks, alternatives, if Not done then..)
 Document in the chart that the above has been performed
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7.  Current Problem- History of present illness
 The proposed surgery – affects type of anaesthesia/ position
 Other known problems- Any comorbidities (DM, HTN,
psychiatric illness)
 Drug history- Present therapy (prescription/ over-the-
counter), alcohol, tobacco
 Allergy history- drugs, food, latex, etc.
 Anesthetic history- Previous anesthetics, operations,
complications, h/o malignant hyperthermia (“allergy to
anesthesia”)
 System review- Screening of any undiagnosed systemic
illnesses
 Miscellaneous- Last oral intake (ER) 7/15/2014 7

8.  General appearance- Comfortable, in distress, sick
looking, physique, wt, ht, BMI
 Vital signs- Temp, pulse, BP, RR
 Head to toe examination- Pallor, icterus, clubbing,
cyanosis, edema, dehydration, peripheral veins,
pre-existing iv cannulae
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9.  dentition- loose or chipped teeth, caps, bridges, or
dentures
 poor anesthesia mask fit expected in edentulous patients and
significant facial abnormalities
 prominent upper incisors, large tongue, short neck suggest
difficulty may be encountered during tracheal intubation
 nostrils
 thyromental distance: 5cms
 Sternomental distance: 12.5 cms
 mandibular protrusion test
 flexon and Extension of the neck
 Cervical spine- Important in trauma, RA, cervical
spondylosis 7/15/2014 9

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11.  A screening evaluation regarding history of tobacco use,
shortness of breath, cough, wheezing, stridor, snoring or
sleep apnea
 recent history of an upper respiratory tract infection
 Patient's ability to carry on a conversation or to walk
without dyspnea
 Physical exam- assess the respiratory rate as well as the
chest excursion, use of accessory muscles
 Auscultation to detect decreased breath sounds, wheezing,
stridor
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12.  Site of surgery
 thoracic, aortic or upper abdominal surgery has highest risk
 Type of surgery
 abdominal aortic aneurysm repair, thoracic, upper abdominal have
highest risks followed by neck, peripheral vascular, and
neurosurgery
 Neurosurgery and neck surgery associated with perioperative
aspiration pneumonia
 Laparoscopic surgery have lesser risk than open surgery
 Duration of surgery
 longer the duration, longer the time exposure to anesthesia
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13.  tobacco/ smoking
 increase carboxy-hemoglobin
 decrease ciliary function
 increase sputum production
 stimulates cardiovascular system secondary to nicotine
 asthma/COPD
 increased airway responsiveness
 drugs may have adverse reactions with anesthetics
 chronic CO2 retention in COPD
 obstructive sleep apnea
 susceptible to the respiratory depressant and airway effects of
sedatives, narcotics, and inhaled anesthetics
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14.  General appearance including weight, BMI
 Vital signs
 Pulse and its characteristics( rate, rhythm, character, volume, delay,
all peripheral pulses)
 BP (if needed in both arms)
 Temperature, RR
 Head to toe examination
 JVP, anemia, cyanosis, clubbing, edema
 Precordial examination
 Inspection/Palpation- apical impulse, heave, thrills
 Auscultation- heart sounds, murmurs
 Auscultation of basal lung fields
 Assessment of liver size and position
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15.  Age
 associated with multisystem disease,
 Previous MI
 5-8% risk of periop reinfarction
 Mortality rate of reinfarction 36-70%
 Risk of reinfarction decreases with time
 30% <3 mnths
 6% >6mnths
 CHF
 symptomatic CHF- predictor of perioperative pulmonary
edema
 Hypertension
 Leading cause of concern
 Not a significant risk factor alone (esp. if <180/110), but due
its end-organ damage like LVF, renal failure and stroke
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16.  DM
 risk of CAD, silent MI, renal insufficiency
 Equal risk as nondiabetics with previous MI
 VHD
 AS- 14 fold greater risk as compared with those without AS
 risk of IE
 Arrhythmias
 Frequent PVCs and nonsinus rhythms
 CHB, LBBB, 2 heart block (Mobitz type II)
 Others
 Smoking, hyperlipidemia, renal failure, anemia, depression,
hypoalbuminemia
 Inflammatory markers: CRP, b-type natriuretic peptide
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17.  Renal disease- important implications for fluid
management and metabolism of drugs.
 Liver disease -associated with altered protein binding,
volume of distribution of drugs, coagulation abnormalities
 Musculoskeletal System- anatomy evaluated for procedures
such as a nerve block, regional anesthesia, invasive
monitoring
 Neurological- history of prior stroke -increased risk for a
perioperative stroke
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18. 7/15/2014 18

19.  CBC
 Ur. / Cr.
 Na/ K
 PT/ INR
 CXR
 ECG
 Urine RE/ME
 Other case pertinent inv.
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20. MET, metabolic
equivalent of the
task. 1 MET =
consumption of
3.5 mL O2/min/kg of
body weight.
Patients with MET less
than 4 or 5 have
higher risk of
perioperative cardiac
morbidity
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21. NYHA: New york Heart Association
CCVSA: Canadian Cardiovascular Society
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22. 7/15/2014 22

23.  administration of drugs prior to anesthesia
 to allay apprehension
 produce sedation
 facilitate the administration of anesthesia to the patient
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24.  Devoid of any side effects
 Minimal depression of respiration and
cardiovascular function.
 Simple and pleasant to take.
 Should act over reasonable period of time.
 Should be effective in all patients.
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25.  Relief of anxiety
 Sedation
 Amnesia
 Analgesia
 Drying of airway secretions
 Prevention of autonomic
reflex responses
 Reduction of gastric fluid
volume and increased pH
 Antiemetic effects
 Reduction of anesthetic
requirements
 Facilitation of smooth
induction of anesthesia
 Prophylaxis against
allergic reactions
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26.  anxiolytics
 Children- syr promethazine (6.25 mg/ml)
 5- 10 ml hs/ cm
 Young adults- diazepam
 5-10 mg hs/ cm
 Elderly –lorazepam
 1- 2mg hs/ cm
 Antiemetics
 Antacids/ ppi
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27.  Hypertension
 Antihypertensive drugs to be continued except Losartan &
Diuretics
• RHD
• Prophylactic antibiotics should be considered
• Patients on anticoagulant therapy- warfarin should be substituted
by heparin 3-5 days prior to surgery
• IHD-
• Anticholinergic mainly atropine to be avoided.
• Aspirin to be discontinued 7 days before surgery
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28. • Bronchodilators, steroids should be continued
• Prophylactic antibiotics in COPD patients
• Inhaled β2-agonists, cromolyn, or steroids should be
continued up to the time of surgery
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29.  Objectives
• avoid hypoglycemia, excessive hyperglycemia,
ketoacidosis
• metformin should be held if there is decreased renal
function- risk for the fear of Lactic acidosis.
• glimepiride (Sulfonylureas) should be held while the pt.
is NPO
• Thiazolidinedione can be continued as they do not
predispose to hypoglycemia
• α-glucosidase inhibitor should be held
• Premedication to avoid aspiration, N/V
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30.  Well-controlled type 2 diabetics do not require insulin for
minor surgery.
 Poorly controlled type 2 diabetics and all type 1 diabetics
having minor surgery and all diabetics having major
surgery need insulin.
 For major surgery, serum glucose > 270 mg/dL, the surgery
should be delayed while rapid control is achieved with
intravenous insulin.
 If the serum glucose >400 mg/dL, surgery should be
postponed and the metabolic state restabilized.
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31.  Administer 1/2 to 2/3rd of the patient's usual intermediate-
acting insulin subcutaneously on the morning of surgery
 In addition to this basal insulin, a regular insulin sliding
scale (RISS) can be added and titrated to blood glucose
measurement.
 Alternatively, an insulin infusion of 1 to 2 U/hr (100 U
regular insulin in 100 mL normal saline at 1 to 2 mL/hr) can
meet basal metabolic needs and be adjusted to maintain
blood glucose at the desired level.
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32.  With either method, a slow glucose infusion (dextrose 5%
in water at 75 to 100 mL/hr) will prevent hypoglycemia
while the patient is fasting.
 Some authorities recommend a combination glucose-
insulin or glucose-insulin-potassium infusions (GIK)
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33. 7/15/2014 33

34. 7/15/2014 34
Management of Diabetes Mellitus in Surgical Patients
http://spectrum.diabetesjournals.org/content/15/1/44.full

35.  Intraoperative GIK solution given to diabetic patients with
CABG operation provides more stable CI, shorter time of
MV, more stable values of potassium which provides
normal rhythm and less AF onset, less insulin to maintain
target glycemia. All the above mentioned provides more
stable intraoperative hemodynamic and better recovery of
diabetic
 Glucose-Insulin-Potassium (GIK) solution used with
diabetic patients provides better recovery after
coronary bypass operations.
Straus S, Gerc V, Kacila M, Faruk C.
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36.  “Sliding scale insulin” is not recommended for the
management of hyperglycemia.
 “set and forget”
 Basal + pre-meal better
https://www.diabetessociety.com.au/documents/Periop
erativeDiabetesManagementGuidelinesFINALCleanJuly
2012.pdf
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37.  Type II patients taking oral agents alone, RISS can be
added to control blood glucose levels.
 Patients receiving chronic insulin can be treated similarly
to the type I patient by giving 1/2 the usual NPH insulin
dose the morning of surgery, supplemented by a RISS, or
an insulin infusion titrated to blood glucose.
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38.  Clear liquids- 2hr
 Breast milk- 4 hr
 Light snacks/ cerelac - 6 hr
 Full meal- 8 hr
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39.  state of drug induced reversible unconsciousness
and loss of protective reflexes
 consist of hypnosis, amnesia, analgesia, relaxation of
skeletal muscles, and loss of autonomic reflexes
 Balanced anesthesia=
hypnotic+ amnesic + analgesics + muscle
relaxant
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40.  Components of GA
 Pre-anesthetic check up (PAC)
 Premedication
 Induction
 Maintenance
 Recovery
 Postoperative Care
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41.  Advantages
 fast onset of anesthesia than inhalation, (10-20 seconds)
 induce total unconsciousness
 avoidance of the excitatory phase of anesthesia (Stage II)
  complications related to induction of anesthesia.
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42.  Propofol (10 mg/ml)-
 <55 yr – 2- 2.5mg/ kg slow iv
 >55 yr- 1-1.5 mg/kg slow iv
 Onset 30- 45 s
 Duration- 20-75 min
 Metabolism- hepatic conjugation
 Excretion- urine
 s/e- injection site burning, hypotension, apnea, rash
pruritus, cardiac s/e
 Most commonly used
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43.  Ketamine (10mg/ml)
 1-4.5 mg/kg slow iv once
 1-2 mg/ kg infusion @ 0.5mg/kg/min
 Produces dissociative anesthesia
 Blocks NMDA receptors
 Onset- 30 s
 Duration- 5 -10 mins
 Metabolised by liver
 Excreted in urine
 s/e- emergence reaction, htn, raised ICP, tachycardia,
hallucinations
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44.  Sodium thiopental
 ultra-short-acting barbiturate
 4–6 mg/kg
 Largely replaced by propofol
 mainly metabolized to pentobarbital
 s/e- hypotension, apnea and airway obstruction
 caution with liver disease, severe heart disease,
severe hypotension, a severe breathing disorder, or a family
history of porphyria
 Etomidate (2mg/ml)
 0.3-.6 mg/ kg iv over a minute
 Onset 60s; duration- 3-5 mins
 Hepatic metabolism, excreted in urine
 s/e- adrenal suppression, pain, apnea, arrythmias
 Less often used
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45.  Advantages:
 Excellent analgesia
 Minimal hemodynamic depression
 Good suppression of endotracheal tube response
 Problems:
 Respiratory depression
 Incomplete suppression of intraoperative awareness
 Used mainly for cardiac anesthesia and also in smaller
doses as a part of balanced anesthesia for non-cardiac
cases
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46.  Fentanyl
 More lipid soluble than morphine
 Rapid onset (60 sec)
 Elimination half time (200 min) is longer than the
duration of clinical effect
 Very highly bound to lung as a function of time. So half-
life of effect depends upon duration of administration
because of an increase in storage.
 Available as IV, transdermal patch & lollipop
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47.  Isoflurane
 1- 3%
 Rapid onset, short acting
 MAC 1.3%
 s/e N/V, hypotension, arrythmias
 Sevoflurane
 1.4- 2.6%
 Onset 2-3 min
 expensive
 s/e hypotension, respiratory irritation, seizures
 Halothane
 potent anesthetic
 MAC 0.74
 20% metabolized in liver
 s/e- liver injury 1in 10,000
 Less preferred 7/15/2014 47

48.  Difficult IV access
 Anticipated difficult airway
 Children
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49.  used for
 facilitate intubation of the trachea
 facilitate mechanical ventilation
 optimize surgical working conditions
 Depolarizing muscle relaxant
 Succinylcholine
 Nondepolarizing muscle relaxants
 Short acting
 Intermediate acting
 Long acting
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50. 7/15/2014 50

51.  Succinylcholine
 Most often used to facilitate intubation
 dose- 1-1.5 mg/kg
 Onset 30-60 seconds
 duration 5-10 minutes
 s/e- Cardiovascular, Fasciculation Muscle pain,
Increase IOP, Increase ICP, intragastric
pressure
Malignant hyperthermia
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52.  Nondepolarizing Muscle Relaxants
 Do not depolarized the motor endplate
 Act as competitive antagonist
 Excessive concentration causing channel blockade
 Act at presynaptic sites, prevent movement of Ach to
release sites
 Long acting
 Pancuronium
 Intermediate acting
 Atracurium, Vecuronium, Rocuronium, Cisatracurium
 Short acting
 Mivacurium
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53.  Vecuronium
 Analogue of pancuronium
 much less vagolytic effect and shorter duration than
pancuronium
 Onset 3-5 minutes
 duration 20-35 minutes
 Intubating dose 0.08-0.12 mg/kg
 Elimination 40% by kidney, 60% by liver
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54.  Neostigmine
 0.03-0.07 mg/kg iv
 Max dose 5mg
 10-20 mins
 Competitive inhibitor of choliesterase
 Reverses action of muscle relaxants
 Administered with anticholinergics
 Atropine (
 Glycopyrrolate (0.2 mg per 1 mg of neostigmine)
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55.  Miller’s Anaesthesia- 7th Edition
 Clinical Anaesthesia – Paul G. Barash, 6th Edition
 ACC/AHA guidelines on perioperative cardiovascular
assessment
 Uptodate 21.2
 Medscape
 www.asahq.org
 http://spectrum.diabetesjournals.org/content/15/1/44.
full
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56.  Thank you!!
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