Summary notes of Anesthesia. These notes were published in 2020. You can download them from: -Mediafire: http://www.mediafire.com/file/wkey81yff7kv3j1/Anesthesia_Q%2526A_2020.pdf/file

1.  Definition of anesthesia:
It is a reversible pharmacologically-induced blocking of pain in the whole body or in a part
of it during surgical, diagnostic, or therapeutic procedures
 Types of anesthesia:
General anesthesia; • Total inhalational anesthesia.
• Total intravenous anesthesia.
• Balanced anesthesia.
Regional anesthesia; • Regional intravenous anesthesia.
• Epidural anesthesia.
• Spinal anesthesia.
• Peripheral nerve block.
• Ganglion or plexus block.
Local anesthesia; • Topical anesthesia.
• Infiltration anesthesia.
Pre-anesthetic assessment
A.The preoperative history:
1. Medication history for
a. Drug allergy.
b. Drug interactions with anesthetics.
2. Current medical problems.
3. Last oral intake.
4. Special habits as smoking, alcohol intake, and drugs addiction.
5. History of previous anesthesia, and surgery to detect previous anesthetic problems
e.g. succinylcholine apnea.
6. Family history to detect hereditary conditions associated with anesthesia
e.g. malignant hyperthermia, myasthenia gravis, cholinesterase abnormalities.
B.Physical examination:
1. Vital signs.
2. Airway.
3. Heart and lung.
4. Nervous system.
5. Other systems appearing affected by history.
C.Investigations & Laboratory evaluation:
- Routine laboratory tests: CBC, liver and kidney function tests, ECG, and serum glucose.
- Detailed investigations for any disease detected by history or physical examination
Anesthesia 2020
“AMPLE” history
Allergies,
Medications,
Past medical history,
Last meal or other intake,
Events leading to presentation
Kareem Alnakeeb

2. Pre-medications
 Definition;
It is administration of drugs in the period of 1-2 hours before induction of anesthesia.
 Q: Enumerate 4 drugs used for pre-anesthetic medications
Drug Aim
1. Anxiolytics: Benzodiazepines
(e.g. Midazolam)
used for anxiolysis, sedation, and amnesia.
2. Opioids (e.g. Morphine):  sympathoadrenal responses (as pressor response
of intubation) especially in ischemic heart patient or
hypertension.
3. Anticholinergics
(e.g. Atropine):
• Anti-sialagogue to  secretions.
•  vagal reflexes
4. Antiemetics
(e.g. Metoclopramide)
• prevent aspiration
•  postoperative nausea and vomiting
5. Antihistaminics • H1 blockers to prevent allergic reactions
• H2 blockers (e.g. Ranitidine) to prevent aspiration
( gastric volume &  gastric pH).
6. Others: Antibiotics, Anticoagulants, etc.
N.B. Anxiolysis is considered the only essential premedication.
General principles
- CNS drugs must be lipid soluble (cross the blood-brain barrier) or be actively transported.
- Drugs with solubility in blood = rapid induction and recovery times.
- Drugs with  solubility in lipids =  potency = 1/MAC
• MAC = Minimum Alveolar Concentration (of inhaled anesthetic) required to prevent 50% of
subjects from moving in response to noxious stimulus (e.g., skin incision).
Examples:
Nitrous oxide (N2O) has  blood and lipid solubility, and thus fast induction and low
potency. Halothane, in contrast, has  lipid and blood solubility, and thus high potency and
slow induction.
 Q: Enumerate 3 drugs used in Intravenous / Inhalational anesthesia.
Intravenous anesthetics: Inhalational anesthetics:
• Thiopentone sodium
• Propofol
• Ketamine
• Halothane
• Isoflurane
• Sevoflurane

3. Intravenous Anesthesia
Thiopentone sodium propofol Ketamine
Indications:
1- Induction of anesthesia.
2- Maintenance of anesthesia
for short procedures.
3- Treatment of status
epilepticus.
4-  intracranial pressure (ICP).
1. Induction of anesthesia.
2. Maintenance of anesthesia
for short procedures.
3. Safe in porphyria.
(ALA synthetase defect)
4. Safe in hepatic disease.
1- Induction of anesthesia
(especially in shocked and
pediatric patients.)
2- Maintenance of anesthesia
for short procedures.
3- Analgesia
Contraindications:
1. Airway obstruction.
2. Previous hypersensitivity
reactions.
3. Porphyria
4. Severe hepatic disease
5. Bronchial asthma.
1- Airway obstruction.
2- Previous hypersensitivity
reactions.
1. Airway obstruction.
2. Hypersensitivity
3. Porphyria.
4. ICP.
5. Hypertension, ischemic heart
disease.
Sideeffects:
(disadvantages)
1- Drowsiness persists for 24-36
hours.
2- Respiratory depression,
bronchospasm, and laryngeal
spasm.
3- CVS depression.
4- Pain and thrombophlebitis
during injection especially in
small veins.
5- Allergic reactions.
1- Excitatory phenomenon.
2- Respiratory depression.
3- CVS depression more than
other agents
4- More pain during injection
especially in small veins.
5- Allergic reactions.
1- Excitatory and emergence
phenomenon.
2-  cerebral metabolic rate &
ICP.
3- Postoperative nausea and
vomiting.
4- Salivation
5- Recovery is often
accompanied by Delirium &
psychomotor activity
6- Unpleasant Dreams
7- Diplopia & nystagmus due to
muscle tone
Pharmacologicalaction
1-CNS;
a) CNS depression.
b) Potent anticonvulsant.
c) Poor analgesic effect.
d) No excitatory or
emergence phenomenon.
e) cerebral metabolic rate
& ICP
f) No postoperative nausea
and vomiting.
1-CNS;
a) CNS depression.
b) No anticonvulsant effect.
c) Poor analgesic effect.
d) Excitatory phenomenon
e)  cerebral metabolic rate
& ICP
f) Antiemetic & Antipruritic
action.
1-CNS;
a) Dissociative anesthesia.
b) Potent analgesic effect.
c) Excitatory and emergence
phenomenon.
d)  cerebral metabolic rate
& ICP
e) Postoperative nausea and
vomiting.
2-Respiratory systems;
a) Respiratory depression.
b) Bronchospasm.
c) Laryngeal spasm.
2-Respiratory systems;
- Respiratory depression more
than thiopentone sodium
2-Respiratory systems;
a) Respiration is maintained
or slightly increased.
b) Bronchodilatation.
c) Pharyngeal and laryngeal
reflexes and patient
airway are maintained.

4. 3-CVS;
a) arterial blood pressure
(ABP).
b) HR (by reflex
tachycardia.)
c) Maintained COP.
3-CVS;
a) ABP more than
thiopentone sodium.
b) HR; no effect
(as it abolishes the
baroreceptor reflex)
3-CVS;
a) ABP.
b) HR.
c) COP (Due to central
stimulation of sympathetic
system.)
4-Neuromusclar effects;
 muscle tone.
4-Neuromusclar effects;
 muscle tone.
4-Neuromusclar effects;
 muscle tone.
5-renal & hepatic blood flow. 5- renal & hepatic blood flow. -
6-  intraocular pressure. - 5-  intraocular pressure.
- 6-  plasma concentration of
cortisol
6-salivation.

5. Inhalational Anesthesia
Halothane Isoflurane Sevoflurane
MAC
0.75 % 1.15 % 2 %
Contraindications:
1- ICT.
2- Malignant hyperthermia.
3- Hypovolemic patient or
severe aortic stenosis
(Cardiac patient)
4- Pheochromocytoma
(as it sensitizes the heart to
catecholamine causing
arrhythmia.)
5- Liver impairment.
1- Severe hypovolemic patient.
2- Ischemic heart disease
(due to possibility of coronary
steal phenomenon.)
1. ICT.
2. Malignant hyperthermia.
3. Severe hypovolemic patient.
4. With Soda lime (mixture of
NaOH & CaO) if fresh gas flow
less than 1 liter/min.
Pharmacologicalaction
1-CNS;
a) CNS depression.
b) Cerebral VD   cerebral
blood flow  moderate
ICP.
1-CNS;
a) CNS depression.
b) Cerebral VD   cerebral
blood flow  slight ICP.
1-CNS;
a) CNS depression.
b) Cerebral VD   cerebral
blood flow  slight ICP.
c) More emergence
agitation.
2-Respiratory systems;
a) Not irritant.
b) Potent bronchodilator.
2-Respiratory systems;
- Irritant to respiratory tract 
cough and breath holding
2-Respiratory systems;
Less effect on respiration
a) Not irritant.
b) Bronchodilator.
3-CVS;
a) ABP
(due to  systemic
vascular resistance)
b) HR
(due to central vagal
stimulation.)
c) COP (due to decreased
myocardial contractility.)
d) Arrhythmia.
3-CVS;
a) ABP
(due to  systemic
vascular resistance.)
b) HR
(due to reflex tachycardia).
c) COP (due to decreased
myocardial contractility.)
d) Coronary steal
phenomenon
3-CVS; Less effect on CVS
a) Slight ABP
(due to  systemic
vascular resistance)
b) No  in HR.
c) COP
4-Neuromusclar effects;
- Moderate muscle tone.
It is a triggering agent for
malignant hyperthermia.
4-Neuromusclar effects;
- Strongly muscle tone
4-Neuromusclar effects;
- Moderate muscle tone.
It is a triggering agent for
malignant hyperthermia.
5-renal & hepatic blood flow. 5-renal & hepatic blood flow. 5- renal BUT  hepatic blood
flow.

6. General anesthesia
 Definition:
- It is an altered physiologic state as a result of reversible drug-induced unconsciousness in which noxious
stimulus neither be perceived nor recalled.
 Parts of general anesthesia:
1. Hypnosis i.e. loss of consciousness.
2. Amnesia i.e. loss of memory.
3. Analgesia i.e. loss of pain sensation.
4. Relaxation i.e. loss of muscle tone and activity.
 Induction of general anesthesia:
1. Intravenous induction.
2. Inhalational induction.
3. Intramuscular induction.
 Maintenance of general anesthesia:
1. Inhalational anesthesia with spontaneous ventilation.
2. Relaxant anesthesia.
 Emergence and recovery:
After tracheal extubation and discontinuing anesthetic agent;
1. 100% O2 is given by a face mask.
2. Support patient airway until respiratory reflexes are intact.
3. Assess the patient muscle power e.g. hand grip, tongue protrusion.
 Q: Complications of general anesthesia
A. CNS
complications
1. Awareness during anesthesia.
2. Delayed recovery.
3. Postoperative pain.
B. CVS
complications
1. Hypotension and hypovolemia.
• Treatment by IV fluids, decreased anesthetics concentration, vasopressors.
2. Hypertension and hypervolemia.
3. Arrythmias.
4. Myocardial ischemia.
5. Deep venous thrombosis (DVT)
C. Respiratory
complications
1. Hypoventilation.
2. Hypoxemia.
• Due to hypoventilation, bronchospasm, airway obstruction,
pneumothorax, decreased inspired fraction of oxygen, etc.
• Treatment; of the cause.
3. Hypercapnia (and hypocapnia).
4. Pneumothorax.
5. Aspiration pneumonia.
6. Complications of laryngoscopy and intubation
e.g. difficult intubation, tubal obstruction.
D. Temperature
changes;
1. Hypothermia.
2. Hyperthermia and malignant hyperthermia.
E. Nausea, vomiting and regurgitation.
F. Drug: Adverse effect & hypersensitivity.

7. Spinal (Intrathecal or Subarachnoid) anesthesia
 Indications:
Analgesia and anesthesia by blocking spinal nerves and dorsal ganglia.
• Preoperative; pre-emptive analgesia.
• Intraoperative; surgeries below the umbilicus (including saddle block surgeries).
• Postoperative; pain control.
 Contraindications:
1. Patient refusal.
2. History of allergy to local anesthetics.
3. Skin infection at the site of injection.
4. Psychosis or dementia.
5. Coagulopathy and anticoagulant therapy.
6. Hypovolemia and shock.
7. Sever aortic or mitral stenosis.
 Q: Complications of spinal anesthesia:
Acute Postoperative;
1- Pain on injection.
2- Total spinal
anesthesia.
3- Hypotension.
4- Vasovagal attack.
1- Backache.
2- Postdural puncture headache (PDPH)
• Cause; leakage of CSF into surrounding soft tissues  CSF
pressure.
• Treatment;
bed rest, good hydration, simple analgesics and caffeine.
Epidural blood patch in resistant cases.
3- Meningitis.
4- Vascular injury  epidural hematoma.
5- Nerve injury
6- Urinary retention.
7- Side effects of local anesthetics.

8. Other Exam Qs NOT included in department source
 Q: Enumerate advantages and disadvantages of Atropine sulphate:
Advantages Disadvantages
1- Bronchodilatation,
 salivary & bronchialsecretion
2-  incidence of bradycardia &
cardiac arrest.
3-  postoperative nausea & vomiting.
1- Mydriasis (interferes with pupillary sign of death)
2- Dryness of all body secretions:
dry mouth & Thirst sensation.
3- Urine retention and constipation.
4- Glaucoma ( IOP)
5- Tachycardia in athletes.
6- Atropine fever (due to block of thermoregulatory
sweating  Hyperthermia)
7- Atropine flush (due to VD in facial blush area)
8-  viscosity of salivary and bronchial
secretions (difficult to aspirate).
9- CNS stimulation.
 Q: Advantages and disadvantages of inhalational anesthesia
Advantages Disadvantages
1- drug administration is rapid & instant due to
large surface area in pulmonary alveolar tissue
2- Local action can be obtained
3- Use Lower doses compared to other routes
4- can bypass Liver
1- Only volatile or gaseous drug material can
be taken
2- Irritant or inflammatory drugs cannot be
taken
3- difficult dose calculation
4- Sometimes this route of administration
causes embarrassing situations
 Q. Spinal anesthesia (advantages & disadvantages)
Advantages Disadvantages
1- Cheap
2- Simple & effective technique
3- Provides adequate analgesia & ms relaxation
4-  surgical blood loss
5-  venous thromboembolic complications
6- NOT affect patient mental status
7- NOT interfere with respiratory functions &
NOT require endotracheal intubation
1- Performed only in surgeries below the
umbilicus e.g. varicocele
2- Requires patient cooperation, So better
avoided in uncooperative, too young,
Psychosis or dementia patient
3- Causes vasodilatation and hypotension,
So contraindicated in shock and stenotic
valvular lesions

9. Halothane Isoflurane Sevoflurane
Advantages
1. Not inflammable,
Not explosive.
2. Rapid induction & recovery.
3. Potent.
Respiratory systems;
4. Not irritant.
5. Potent bronchodilator.
6. Safe in children & in BA
1. Not inflammable,
Not explosive.
2. Rapid induction & recovery.
3. Potent.
Neuromuscular effects;
4. Strongly muscle tone
1. Minimal / Less pungent odor
2. Useful in mask induction.
CVS;
3. No  in HR
4. Lack of coronary VD.
5. No coronary steal
phenomena.
Respiratory systems;
Less effect on respiration
6. Not irritant.
7. Bronchodilator.
Sideeffects:
(disadvantages)
CNS;
1. CNS depression.
2. moderate ICP.
CVS;
3. Arrhythmia
Neuromuscular effects;
4. malignant hyperthermia
5. renal & hepatic blood flow.
6. Hepatotoxicity
7. Potent uterine Relaxant
1. Pungent odor.
2. Not used in mask induction.
CNS;
3. CNS depression.
4. slight ICP.
CVS;
5. HR
6. Coronary steal phenomenon
Respiratory systems;
7. Irritant to respiratory tract 
cough and breath holding
8. renal & hepatic blood flow.
1. Less soluble in blood &
tissues; less potent.
Neuromuscular effects;
2. malignant hyperthermia
3. renal BUT  hepatic blood
flow.
Thiopentone Na propofol Ketamine
Advantages
1- Rapid & Pleasant induction
with Rapid recovery.
2- No  ICP
3- No post op. nausea and
vomiting.
4- No apparatus needed.
5- Diathermy can be used.
1- Rapid and complete recovery.
2- Can be used by infusion
for ICUsedation
3- Can be used in
ambulatory surgery
4- Safe in porphyria.
5- Safe in hepatic disease
6- Can be used in COPD
patients.
7- Drug of choice in patients
with malignant
hyperthermia.
8- Antiemetic effect.
9- Antipruritic
action associated
with neuron block
10- Neuroprotective
effect on CNS.
11- Anti-oxidant
effect.
1- Used in Shocked and pediatric
patients.
2- Potent analgesia & amnesia
3- No Respiratory depression
4- Potent Bronchodilatation
5- Used in BA.

10.  Q: compare () Sevoflurane and isoflurane.
Isoflurane Sevoflurane
Complete fluorination of halogenated methyl
ethyl ether.
Complete fluorination of methyl isopropyl
ether.
High degree of solubility. Less soluble in blood & tissues; less potent.
Pungent odor. Minimal odor / Less pungent odor.
Not used in mask induction. Useful in mask induction.
CVS;
- HR.
- Coronary VD.
- Coronary Steal phenomenon
CVS;
- No ↑ in HR
- Lack of coronary VD.
- No coronary steal phenomena.
Respiratory systems;
- Irritant to respiratory tract causing cough
and breath holding
Respiratory systems;
Less effect on respiration
a) Not irritant.
b) Bronchodilator.