Transcript General Anesthesia

GHAZI ALDEHAYAT MD
Ancient and Mediaeval times
Which is the best face?
Anesthesia
 Anesthesia
 Intensive care
 Chronic pain management
Anesthesia
 Anesthesia
 CPR
 Acute Pain control
 Difficult Lines
 Evaluating critical patints
Anesthesia
 Theatre
 Radiology
 Interventional radiology
 Cardiology
 ECT
 GI
Types Of Anesthesia
Types of Anesthesia
 General Anesthesia
 Regional Anesthesia
 Local Anesthesia
 Sedation
General Anesthesia
 Preoperative evaluation
 Intraoperative management
 Postoperative management
Purpose of preoperative visit
 Medical assessment of the patient.
 Decide the type of anesthesia.
 Establish rapport with the patient.
 Allay anxiety and decrease pain.
 Obtain informed consent.
 Ask for further investigation.
 Decide risk versus benefit .
 Prescribe medications.
Pre-Operative Assessment
History
 Indication for surgery
 Surgical/anesthetic hx: previous
anesthetics/complications, previous
intubations,
 Medications, drug allergies
• Medical history
 CNS: seizures, CVA, raised ICP, spinal disease,
arteriovenous malformations
 CVS: CAD, MI, CHF, HTN, valvular disease,
dysrhmias, PVD, conditions requiring endocarditis
prophylaxis, exercise tolerance, CCS class, NYHA class
 Resp: smoking, asthma, COPD, recent URTI, sleep
apnea
 GI: GERD, liver disease
 Renal: insufficiency, dialysis
 Hematologic: anemia, coagulopathies, blood
dyscrasias
 MSK: conditions associated with difficult intubations
– arthritis, RA, cervical tumours, cervical
infections/abscess, trauma to C-spine, Down
syndrome,
scleroderma, obesity
 Endocrine: diabetes, thyroid, adrenal disorders
 Other: morbid obesity, pregnancy, ethanol/other drug
use
FHx: malignant hyperthermia, atypical cholinesterase
(pseudocholinesterase), other abnormal drug
reactions
Physical Examination
Physical exams of all systems.
Airway assessment to determine the likelihood of
difficult intubation
 Bony landmarks and suitability of areas for regional
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anesthesia if relevant
Focused physical exam on CNS, CVS and respiratory
(includes airway) systems
General, e.g. nutritional, hydration, and mental status
Pre-existing motor and sensory deficits
Sites for IV, central venous pressure (CVP) and
pulmonary artery (PA) catheters,
regional anesthesia
Investigations: According to( ranged from none to most
comlicated)
 Age
 Surgery
 Medical condition
As clinically indicated
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Low risk – no further evaluation needed
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Intermediate risk – non-invasive stress testing
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High risk – proper optimization +/delaying/canceling procedure
 American Society of Anesthesiology (ASA)
classification
 Common classification of physical status at time of
surgery
 A gross predictor of overall outcome, NOT used as
stratification for anesthetic risk (mortality rates)
 ASA 1: a healthy, fit patient (0.06-0.08%)
 ASA 2: a patient with mild systemic disease, e.g.
controlled Type 2 diabetes, controlled essential HTN,
obesity (0.27-0.4%), smoker
 ASA 3: a patient with severe systemic disease that limits
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activity, e.g. angina, prior MI, COPD (1.8-4.3%), DM,
obesity
ASA 4: a patient with incapacitating disease that is a
constant threat to life, e.g. CHF, renal failure, acute
respiratory failure (7.8-23%)
ASA 5: a moribund patient not expected to survive 24
hours with/without surgery, e.g. ruptured abdominal aortic
aneurysm (AAA).
ASA 6 : Brain death patient
For emergency operations, add the letter E after
classification
 Medications:
 Pay particular attention to CVS and resp meds,
narcotics and drugs with many side effects and
interactions• prophylaxis.
 Risk of GE reflux: Na citrate 30 cc PO 30 mins hour
pre-op.
 Risk of adrenal suppression – steroid coverage
 Risk of DVT – heparin SC,LMW Heparin, Mechanical
methods.
 Optimization of co-existing disease ^ bronchodilators
(COPD, asthma), nitroglycerine and beta-blockers
(CAD risk factors)
 Pre-operative medications( most of the timeShould
be continued).
 May be stopped stop eg:
 Oral hypoglycemics – stop on morning of surgery
 Antidepressants.
 Pre-operative medication to adjust:
Insulin, prednisone, coumadin, bronchodilator
 Decide, whether to proceed with surgery ,to send
patient for further management or to cancel the
operation.
 Discus anesthetic options.
 Decide which is the most useful for the patient.
 Informed concent.
 Risk stratification .
Types of anesthesia
GENRAL ANESTHESIA
REGIONAL ANESTHESIA
LOCAL ANESTHESIA.
GENERAL ANESTHESIA
Airway management
 Endotracheal intubation( Body cavities, Full stomach,
prone position, compromised, Very long operations,
Airway involvment )
 Laryngeal mask Airway( peripheral, No indication for
ETT)
 Mask( very short, no indication for ETT)
Ventilation
 Spontaneous ( No muscle relaxant)
 Controlled ( With muscle relaxant)
GENERAL ANESTHESIA
 PREPARATION
 monitoring
 position
 Intravenous fluid
 Warming
 CONDUCT OF ANESTHESIA
 PERIOPERATIVE MEDICINE
 Monitoring: according to paitent medical condition
and surgery proposed
 Basic: ECG, NIBP,SpO2, EtCO2, Temp,FiO2,
Anesthetic gases, Airway pressure, The presence of
anesthetist all throug
procedure.
 Others: Nerve stimulator, Invasive Bp, CVP, CO, BIS,
PA Catheter, TEE, UO
Lab tests, ABGs, CBC, LFT , Coagulation, TEG
Basic Principles of Anesthesia
 Anesthesia defined as the abolition of sensation
 Analgesia defined as the abolition of pain
 “Triad of General Anesthesia”
 need for unconsciousness
 need for analgesia
 need for muscle relaxation
Hypnosis
(unconsciousness
)
Induction
Maintinance
Recovery
Intravenous(eg:T
hiopentone,Prop
ofol)
Inhalational(
sevoflurane,Halo
thane)
Inhalational
Intravenous
Discontinue
Analgesia Systemic( opiods,
Fentanyl,Remifen
tanil,Alfentanil)
Muscle
Relaxation
Depolarizing
(suxamethoniom
)
Non
Depolarizing
(steroids,
vecuronium)
Benzylisoquinolo
nium Cis
atracurium)
Systemic: Goo)Multimodal)
(opiods,NSAIDS)
d Analgesi
Regional( Opioids,Regional
Epidural,Spinal)
, Local
LA
NSAIDS
N2O
Parasetamol
Non
Reversal by
Depolarizing Anticholinstrases
( Neostigmine,)&
Atropine
Intravenous Anesthetic Agents
Thiopental
 Thiobarbiturates
 Uses for iduction, decrease ICP, Status epilepticus
 CNS: Hypnosis within 30 seconds ,decreased
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intracrainial pressure.
CVS depression, hypotension, tachycardia
Respiratory depression, spasm
CI: porphyria
Arterial injection
Intravenous Anesthetic Agents
PROPOFOL ( Deprivan)
 USES: induction, maintenance, sedation in the ICU,
sedation
 Contra indicated in children.
 CNS: Hypnosis within 30 seconds ,decreased
intracrainial pressure.
 CVS: depression more than Thiopental
 Respiratory: Depression, no spasm
 Caloric load in the ICU, propfol infusion syndrome
Intravenous Anesthetic Agents
Ketamine ( ketalar)
 Phencyclidine
 Uses, shock, burn, field.
 CNS, dissociation, hallucination, analgesia,
 Increased intracrainial pressure.
 CVS Stimulation, hypertension, tachycardia
 Respiratory, less depression.
Intravenous Anesthetic Agents
 Etomidate
 Stable cardiovascular
 Steroid depression
Inhalational Anaesthesia
Halothane
Enflurane
Isoflurane
Sevoflurane
Desflurane
N2o
Xenon
Inhalational
Anesthesia induced by inhalational effec
different in their potency, indicated by MAC.
Different in rapidity of induction and recovery.
Common pharmacological properties,
CVS depression with tachy or bradycardia
RESP Depression.
CNS increased intracranial pressure
Precipitate Malignant hyperthermia except N2o,
Xenon
Opioid
Fentanyl
Alfentanl
Remifentanil
Morphine
Pethidine
All have almost the same pharmacodynamics as
Morphine, Analgesia, Sedation , Respiratory
depression, Nausea and vomiting, meiosis,
constipation.
Different in their pharmakokinitcs.
Muscle relaxant
Depolarizing
Suxamethonium
Short acting, rapid onset,
Many Side effects, hyperkalemia, arrythmias,
Precipatate Malignant Hyperthermia.
Muscle pain ,Scoline apnea.
Non Depolarizing:
Aminosteroid : Pancuronium, Vecuronium organ
metabolism
Benzylisoquinolonium: atracurium : Histamine release,
Long acting.
Never give Muscle relaxant without Anesthesia (
sleeping)
Local anaesthetics
Lidocaine, lignocaine,xylocaine
Bupivacaine ( marcaine)
Cocaine
Procaine
 Regional ( spinal , epidural)
 Local
 Different side effects
 Marcaine CI
by intravenous
 LA toxicity. Maximum doses,
 Perioral numbness, tinnitus, conulsions, resp
depression, Cardiac arrest
 Treatment, ABC, symptomatic, intralipid( propofol)
Reversal
Neostigmine
Atropine
Monitoring
Basic ( ECG, BP, SPO2, EtCO2) Observation
Advanced ( IBP , CVP, CO ….ETc
Awareness
Awarness
Definition
Types
Effect
Causes
Manegment
Thank you