Contents : Anesthesiology instruments General features of anesthetic instruments Anesthetic cylinders Pin index Anesthetic gases Anesthetic machines and circuits Mapleson system Oxygen control devices Devices for co2 absorption Dead space Endotracheal tube Laryngoscopy and endotracheal intubation Nasotracheal intubation Laryngeal mask airway Trendelenberg position General features of monitoring during anesthesia Central venous pressure monitoring Pulmonary artery catheter Capnogram Anesthetic complications Air embolism Respiratory complications Malignant hyperthermia Intraoperative and postoperative complications Resuscitation Mendelson syndrome Hypothermia in anesthesia Clinical anesthesia History of anesthesia Stages of anesthesia Preanesthetic assessment Pediatric anesthesia Anesthesia in head injury Cardiovascular anesthesia Anesthesia in ent Obstetric anesthesia Anesthesia in orthopedics Respiratory anesthesia Day care anesthesia Drugs of anesthesia Preanesthetic drugs General features of anesthetic drugs Inhalational anesthetics Minimum alveolar concentration Partition coefficient General features of inhalational anesthetics Xenon Nitrous oxide Trilene Ether Helium Chloroform Halothane Enflurane Isoflurane Desflurane Sevoflurane Methoxyflurane Intravenous anesthetics General features of intravenous anesthetics Propofol Ketamine Thiopentone Etomidate Local anesthetics General features of local anesthetics Bupivacaine Lignocaine Prilocaine Cocaine Procaine Bier’s block/IVRA Peribulbar and retrobulbar block Stellate ganglion block Brachial plexus block Celiac plexus block Neuromuscular blockers General features of neuromuscular blockers Depolarising muscle relaxants – Succinly choline Features of non depolarizing muscle blockers D-tubocurarine Pancuronium Vecuronium Mivacurium Atracurium Gallamine Alcuronium Spinal, epidural and caudal anesthesia and pain management Splanchnic block Neuraxial blockade Spinal anesthesia Epidural anesthesia Caudal anesthesia Other blocks Pain General features of pain Assessment of pain Analgesic drugs For more details, visit www.medpgnotes.com You can send your queries to medpgnotes@gmail.com

1. ANESTHESIOLOGY
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1ANESTHESIOLOGY INSTRUMENTS
CONTENTS
ANESTHESIOLOGY INSTRUMENTS................................................................................................................................. 4
GENERAL FEATURES OF ANESTHETIC INSTRUMENTS ............................................................................................... 4
ANESTHETIC CYLINDERS............................................................................................................................................ 4
PIN INDEX.................................................................................................................................................................. 4
ANESTHETIC GASES................................................................................................................................................... 4
ANESTHETIC MACHINES AND CIRCUITS.................................................................................................................... 5
MAPLESON SYSTEM .................................................................................................................................................. 5
OXYGEN CONTROL DEVICES...................................................................................................................................... 5
DEVICES FOR CO2 ABSORPTION ............................................................................................................................... 6
DEAD SPACE.............................................................................................................................................................. 6
ENDOTRACHEAL TUBE .............................................................................................................................................. 7
LARYNGOSCOPY AND ENDOTRACHEAL INTUBATION............................................................................................... 7
NASOTRACHEAL INTUBATION................................................................................................................................... 9
LARYNGEAL MASK AIRWAY....................................................................................................................................... 9
TRENDELENBERG POSITION...................................................................................................................................... 9
GENERAL FEATURES OF MONITORING DURING ANESTHESIA .................................................................................. 9
CENTRAL VENOUS PRESSURE MONITORING .......................................................................................................... 10
PULMONARY ARTERY CATHETER............................................................................................................................ 10
CAPNOGRAM .......................................................................................................................................................... 11
ANESTHETIC COMPLICATIONS .................................................................................................................................... 11
AIR EMBOLISM........................................................................................................................................................ 11
RESPIRATORY COMPLICATIONS .............................................................................................................................. 11
MALIGNANT HYPERTHERMIA ................................................................................................................................. 12
INTRAOPERATIVE AND POSTOPERATIVE COMPLICATIONS .................................................................................... 12
RESUSCITATION....................................................................................................................................................... 13
MENDELSON SYNDROME........................................................................................................................................ 13
HYPOTHERMIA IN ANESTHESIA............................................................................................................................... 14
CLINICAL ANESTHESIA................................................................................................................................................. 14
HISTORY OF ANESTHESIA........................................................................................................................................ 14
STAGES OF ANESTHESIA.......................................................................................................................................... 14
PREANESTHETIC ASSESSMENT................................................................................................................................ 14
PEDIATRIC ANESTHESIA .......................................................................................................................................... 15

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2ANESTHESIOLOGY INSTRUMENTS
ANESTHESIA IN HEAD INJURY ................................................................................................................................. 15
CARDIOVASCULAR ANESTHESIA.............................................................................................................................. 15
ANESTHESIA IN ENT ................................................................................................................................................ 16
OBSTETRIC ANESTHESIA.......................................................................................................................................... 16
ANESTHESIA IN ORTHOPEDICS................................................................................................................................ 16
RESPIRATORY ANESTHESIA ..................................................................................................................................... 16
DAY CARE ANESTHESIA ........................................................................................................................................... 17
DRUGS OF ANESTHESIA .............................................................................................................................................. 17
PREANESTHETIC DRUGS.......................................................................................................................................... 17
GENERAL FEATURES OF ANESTHETIC DRUGS ......................................................................................................... 17
INHALATIONAL ANESTHETICS ..................................................................................................................................... 18
MINIMUM ALVEOLAR CONCENTRATION................................................................................................................ 18
PARTITION COEFFICIENT......................................................................................................................................... 18
GENERAL FEATURES OF INHALATIONAL ANESTHETICS........................................................................................... 18
XENON..................................................................................................................................................................... 19
NITROUS OXIDE....................................................................................................................................................... 19
TRILENE ................................................................................................................................................................... 20
ETHER...................................................................................................................................................................... 20
HELIUM ................................................................................................................................................................... 20
CHLOROFORM......................................................................................................................................................... 20
HALOTHANE............................................................................................................................................................ 20
ENFLURANE............................................................................................................................................................. 21
ISOFLURANE............................................................................................................................................................ 22
DESFLURANE ........................................................................................................................................................... 22
SEVOFLURANE......................................................................................................................................................... 22
METHOXYFLURANE................................................................................................................................................. 23
INTRAVENOUS ANESTHETICS...................................................................................................................................... 23
GENERAL FEATURES OF INTRAVENOUS ANESTHETICS ........................................................................................... 23
PROPOFOL............................................................................................................................................................... 24
KETAMINE ............................................................................................................................................................... 24
THIOPENTONE......................................................................................................................................................... 25
ETOMIDATE............................................................................................................................................................. 26
LOCAL ANESTHETICS ................................................................................................................................................... 26
GENERAL FEATURES OF LOCAL ANESTHETICS......................................................................................................... 26

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BUPIVACAINE .......................................................................................................................................................... 28
LIGNOCAINE............................................................................................................................................................ 28
PRILOCAINE............................................................................................................................................................. 29
COCAINE.................................................................................................................................................................. 29
PROCAINE................................................................................................................................................................ 29
BIER’S BLOCK/IVRA ................................................................................................................................................. 29
PERIBULBAR AND RETROBULBAR BLOCK................................................................................................................ 30
STELLATE GANGLION BLOCK................................................................................................................................... 30
BRACHIAL PLEXUS BLOCK........................................................................................................................................ 30
CELIAC PLEXUS BLOCK............................................................................................................................................. 30
NEUROMUSCULAR BLOCKERS .................................................................................................................................... 31
GENERAL FEATURES OF NEUROMUSCULAR BLOCKERS.......................................................................................... 31
DEPOLARISING MUSCLE RELAXANTS – SUCCINLY CHOLINE ................................................................................... 31
FEATURES OF NON DEPOLARIZING MUSCLE BLOCKERS......................................................................................... 33
D-TUBOCURARINE................................................................................................................................................... 33
PANCURONIUM ...................................................................................................................................................... 33
VECURONIUM ......................................................................................................................................................... 34
MIVACURIUM.......................................................................................................................................................... 34
ATRACURIUM.......................................................................................................................................................... 34
GALLAMINE............................................................................................................................................................. 34
ALCURONIUM ......................................................................................................................................................... 35
SPINAL, EPIDURAL AND CAUDAL ANESTHESIA and pain management ...................................................................... 35
SPLANCHNIC BLOCK ................................................................................................................................................ 35
NEURAXIAL BLOCKADE............................................................................................................................................ 35
SPINAL ANESTHESIA................................................................................................................................................ 35
EPIDURAL ANESTHESIA ........................................................................................................................................... 37
CAUDAL ANESTHESIA.............................................................................................................................................. 37
OTHER BLOCKS........................................................................................................................................................ 38
PAIN ............................................................................................................................................................................ 38
GENERAL FEATURES OF PAIN.................................................................................................................................. 38
ASSESSMENT OF PAIN............................................................................................................................................. 38
ANALGESIC DRUGS.................................................................................................................................................. 39

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4ANESTHESIOLOGY INSTRUMENTS
ANESTHESIOLOGY INSTRUMENTS
GENERAL FEATURES OF ANESTHETIC INSTRUMENTS
Rotameter Constant pressure, variable orifice, flow meter for gases
and liquids
Rotameter Height of bobbin rise indicates flow rate
MC cause of inaccurate reading in Rotameter 1
st
Static Electricity, 2
nd
Dirt
Wright spirometer Used for calculation of expired volumes
Types of Pneumatographs measuring airway resistance Fleisch’s type, Venturi type, Turbine type
Used to protect airway LMA, endotracheal tube, combitube
Least damage to blood elements Membrane oxygenator
ANESTHETIC CYLINDERS
Filling ratio of anesthetic cylinder Filling ratio is the weight of the fluid in
the cylinder divided by weight of water
required to fill the cylinder
Color of oxygen cylinder Black cylinder with white shoulders
Color of ethylene cylinder Purple
Color of nitrous oxide cylinder Blue
Color of cyclopropane cylinder Orange
PIN INDEX
Pin index of nitrous oxide 3,5
Pin index Pin is present on machine, not effective if wrong gas is
filled in cylinder, hole position on cylinder valves
System preventing Incorrect gas Cylinder attachment Pin Index Safety system
ANESTHETIC GASES
Gas filled as liquid in cylinders CO2, N20, cyclopropane
Gas stored in liquid form N2O
Nitrous oxide Cylinder blue in color, MAC 105
Tare weight is used for Gas Cylinders
For high pressure storage of gases, cylinders are made
of
Molybdenum steel
Pressure of N2O at 20*C 745 psi
High pressure in gas cylinder indicate Impurities in N2O
Critical temperature of air -140.6*C
Critical temperature of oxygen -119*C
Critical temperature of N2O 36.5*C

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ANESTHETIC MACHINES AND CIRCUITS
Anesthesia breathing circuit Cylinder is a part of high pressure system, O2 flush
delivers < 35 liters
Boyle’s machine Continuous flow, low resistance
Boyle’s law At constant temperature, volume of a given mass varies
inversely with its absolute pressure
High pressure system in anesthesia machine is delivered
by
Hanger yoke
Principle of Boyle’s apparatus Continuous Flow
Heidbrink meter in Boyle’s apparatus Indicates flow of gases
Bernoulli principle In laminar flow, velocity of flow through a tube is
inversely related to its pressure against the size of tube
Modified bernoulli Pressure change = 4 * (velocity)^2
Clayton is used in closed breathing circuit as Indicator
MAPLESON SYSTEM
Most efficient anesthetic circuit for GA with
spontaneous respiration
Mapleson A
Air flow in Magill’s circuit (Mapleson A) Equal to minute volume
Magill’s circuit Ideal for adults, semiclosed, spontaneous breathing is
must
NOT suited for both controlled and assisted ventilation Mapleson A
No corrugated tube in Mapleson C
Bain circuit Mapleson type D, can be used for both controlled and
spontaneous ventilation
Bain circuit Inner tube for inspiration, circuit of
choice for controlled ventilation, light
weight, fresh gas flow should be 1.5 times of
minute volume
Mapleson system used in children Ayer T tube
Ayre’s T piece Mapleson E
Features of Ayre’s T piece No reservoir bag, no expiratory valve
Most appropriate circuit for ventilating spontaneously
breathing infant during anesthesia
Jackson Ree’s modification of Ayre’s T piece
Rebreathing prevention valve Light, well designed, used at expiratory end of tube
Rebreathing circuit To and fro circuit, circle system, water system
OXYGEN CONTROL DEVICES
Assessment of oxygen in a cylinder attached to
anesthesia machine
Bourdon pressure gauge
Used for proper oxygen flow to patient Proportionator between N2O and O2 control valve,
different pin index, calibrated oxygen corrected analysis
System Maintaining O2 concentration by limiting N2O
flow
Pneumatic Interlock Oxygen Ratio Monitor Controller
(ORMC)

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System Maintaining 25% O2 concentration and
Maximum N2O:O2 flow ratio of 3:1
Link 25 Proportion Limiting system(Datex Ohmeta
System)
Safety measures to prevent delivery of hypoxic mixture
to patient
Location of oxygen valve after N2O valve, location of fail
safe valve downstream from nitrous oxide supply
source
Oxygen concentrator Zeolite activation, delivers O2,requires power supply
Oxygen content in anesthetic mixture 33%
Fixed performance oxygen provided by Venturi mask
Delivery of oxygen in basic life support Through mask
Humidification of air is needed in Face mask
Oxygen delivery regulated by Oxygen tent, oxygen apparatus, poly mask, venti mask
Maximum O2 concentration achieved in venturi mask 60%
Side effects of oxygen therapy Absorption atelectasis, decreased pulmonary
compliance, decreased vital capacity, endothelial
damage
Oxygen given during anesthesia to prevent Hypoxia
90% oxygen by Non rebreathing mask
Safe oxygen concentration in therapy is to achieve PaO2 > 50 mm Hg
Humidity of dry 100% oxygen 0 mg H2O litre
Artificial nose Heat and moisture exchanger
DEVICES FOR CO2 ABSORPTION
CuSO4 present in Amsorb
Ba (OH)2 present in Baralime
Decrease CO2 absorption High flow, medium granule, No resistance in circuit
Decreases CO2 absorption Increased tidal volume, increased dead
space
Increases CO2 absorption Resistance in circuit
Soda lime is used to absorb CO2 in Closed circuit system
Reacts with soda lime Trilene
Main component of soda lime in closed circuit Calcium hydroxide
Composition of soda lime 90% Ca(OH)2 + 5% NaOH + 1% KOH
NOT a component of sodalime Ba OH2
Soda lime does NOT contain CaCl
NOT true about soda lime Used in treatment of alkalosis
Water is used for hardening in Soda lime
Color change in Mimoza 2 Red to white
Signs of soda lime exhaustion Change of color of granules, rise in ETCO2
in capnography, rise in BP followed by
fall, rise in pulse rate, deepening of
spontaneous respiration, increased oozing
from wound, increased sweating
DEAD SPACE
Normal dead space 30% of tidal ventilation

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Anatomical dead space is increased by Atropine, Halothane, Inspiration
Dead space is increased by Anti cholinergic drugs, standing, hyperextension of neck
Physiological dead space is decreased by Neck flexion
Anatomical dead space in Supine position Decreases
Anatomical dead space decreased by Massive pleural effusion
Dead space NOT increased by Endotracheal intubation
Least amount of CO2 present in Anatomical dead space - end inspiration phase
ENDOTRACHEAL TUBE
Size of endotracheal tube in 1 – 6 months
aged
2 – 4 mm
Size of endotracheal tube in 6 months to 1
year aged
3.5 – 4.5 mm
Size of endotracheal tube in 1 – 6 years [Age/3] + 3.5
Size of endotracheal tube more than 6
years
[Age/4] + 4.5
Length of endotracheal tube in neonate 10 – 11 cm
Length of endotracheal tube in elder
children
[age/2] + 12
Reasonable size of endotracheal tube in 3 year old 4.5 mm
Curved blade in adult laryngoscope is Macintosh
Endotracheal cuff High volume low pressure, low volume high pressure
Size of endotracheal tube in children less than 6 years (Age/3.5)+3.5
Diameter and length of endotracheal tube in full term
infant
3.5 mm and 12 mm
McIntosh tube for Adults
Magill’s tube Children
Armoured endotracheal tube is used in Neurosurgery
RAE endotracheal tube Red
RAE tube is used in LASER surgery
Diameter of ET tube in child less than 1000 g 2.5,3
Direct laryngoscope in right handed person Left hand
Type of endotracheal tube and blade in children Uncuffed tube with straight blade
Cuff pressure in ET tube should not exceed 23 mm Hg
LARYNGOSCOPY AND ENDOTRACHEAL INTUBATION
High airway resistance seen in Main bronchus
Airway assessment Mallampatti grading, Cormack and
Lehare (based on laryngoscopy), Wilson’s
scoring, LEMON law
LEMON law Look externally, evaluate 3-3-2 rule,
Mallampatti, Obstruction, Neck mobility
Normal thyromental distance >6.5 cm
Mallampatti grading for Inspection of oral cavity before intubation

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Mallampatti classification is based on Opening of mouth
Clinical predictor of a difficult intubation
is postulated to be responsible for a grade
III Mallampatti view of oral cavity
Large tongue
NOT an indication for endotracheal intubation Pneumothorax
Both orotracheal and nasotracheal intubation is
contraindicated in
Acute laryngotracheobronchitis
Difficulty in intubation Burns in head and neck, Still’s disease, Down’s
syndrome
Features of difficult airway Miller’s sign, TMJ ankylosis, micrognanthia and
macroglossia
Used in difficult intubation Helium O2 mixture, entoxon, sevoflurane
Maneuver performed during laryngoscopy and
intubation
Flexion of neck, extension of head at atlantooccipital
joint, in straight blade laryngoscope epiglottis is lifted
by tip, upper incisors are most vulnerable to damage by
laryngoscopy so laryngoscope should not be levered
against them
Endotracheal intubation in children Small morbidity on prolonged intubation
NOT seen during laryngoscopy Hypotension
Sellick’s original description of cricoid
pressure
Extending head
Sellick maneuver is used to prevent Gastric aspiration
Sellick maneuver is effective in prevention
of
Passive regurgitation and subsequent
aspiration
NOT a maneuver performed during laryngoscopy Laryngoscope is lifted upwards levering over the upper
incisors
Effective adjuvant in attenuating
hypertension and tachycardia associated
with laryngoscopy and intubation
Succinylcholine
High potassium level with scoline for
intubation occurs with
Chronic paraplegia
Most accurate measurement of correct placement of ET
tube
End Tidal CO2
Correct placement of endotracheal tube judged by Arterial CO2, Breath sounds, Chest X ray
Speedy intubation, breath sounds were observed to be
decreased on left side and high end tidal CO2
Endobronchial intubation
Laryngoscopy and intubation is associated with Hypertension and tachycardia, raised IOT, raised ICT,
decreased lower esophageal sphincter tone, arrhythmia
Endotracheal intubation Reduces normal anatomical dead space
A child has been intubated and connected to anesthesia
machine. A problem has occurred in anesthesia
machine and the child collapsed after 2 minutes. What
to do next
Increase the flow
Laryngeal complication of Prolonged ET intubation Stenosis, Ulceration, Abductor paralysis
Prevention of intubation induced
laryngeal spasm
Local anesthesia, fentanyl, diltiazem
Drug that can precipitate reflux Promethazine
Treatment of severe tracheal stenosis due to
endotracheal intubation for more than 2 weeks
Tracheal resection and end to end anastomosis

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Surgery for extensive tracheal stenosis Grillo or Barclay procedure
NASOTRACHEAL INTUBATION
Merits of nasotracheal intubation Good oral hygiene
Nasal intubation is contraindicated in CSF rhinorrhoea
LARYNGEAL MASK AIRWAY
Supraglottic type of airway management Laryngeal mask airway
NOT a definite airway Laryngeal mask apparatus
NOT an advantage of laryngeal mask airway Aspiration is prevented
Laryngeal mask airway NOT used for Large tumor in oral cavity
Laryngeal mask airway is used for Maintenance of airway
Laryngeal mask airway More reliable than face mask, alternative to
endotracheal tube, does NOT require laryngoscope and
visualization
LMA Intubation can be done, size 1 for neonates, size 3 for
adults
Plan C of anesthetic airway management Insertion of laryngeal mask airway and fibroptic
bronchoscopy
TRENDELENBERG POSITION
Maximum vital capacity decreased in Trendelenberg position
Trendelenberg position decrease Vital capacity, FRC, compliance
Trendelenberg position does NOT cause decrease in Respiratory rate
Position with least vital capacity in GA Trendelenberg
GENERAL FEATURES OF MONITORING DURING ANESTHESIA
Individual operative awareness by Bispectral imaging
Organ at greatest risk of ischemia under
conditions of normovolemic hemodilution
Heart
Best to monitor intraoperative myocardial ischemia Transesophageal echocardiography
Most sensitive and practical technique to detect
myocardial ischemia in perioperative period
Regional wall motion abnormality detected with help of
2D transesophageal echocardiography
5th
vital sign Pulse oximetry
Pulse oximetry At 660 nm, oxyhemoglobin reflect more light than
deoxyhemoglobin, reverse is true at 940 nm
Pulse oximetry detects inaccurately in presence of Nail polish, methemoglobinemia, skin pigmentation
Inadequate ventilation during intraoperative period is
best assessed by
Pulse oximetry
Beer Lambert Law Pulse oximetry

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Oxygen saturation is measured by Pulse oximeter
Used to monitor respiration in non intubated neonate Impedance pulmonometry
Non ventilated baby is in incubator, best way to
monitor baby’s breathing and detect apnea
Impedance pulmonometry
A postoperative patient with pH 7.25 MAP 60 mm Hg
treated with
Fluid therapy with CVP monitoring
Least affected during anesthesia Brainstem auditory evoked potential
Somatosensory evoked potential is
important during
Thoracic and abdominal aorta surgery
MC nerve used for monitoring during anesthesia Ulnar nerve
Modality best utilized for neuromuscular
monitoring during maintenance of
anesthesia
Train of four
NOT a cause of bacterial sepsis in ICU patient on
invasive monitoring
Humidified air
CENTRAL VENOUS PRESSURE MONITORING
MC vein for CVP monitoring Right Internal Jugular Vein
While inserting CVP, patient developed respiratory
distress
Pneumothorax
MC complication of central venous catheter Catheter related infection
Complications of CVP line Airway injury, hemothorax, septicemia, air embolism,
pulmonary edema
CVP monitoring is most useful in Guiding hemodynamic therapy
In a patient with multisystem trauma, presence of
hypotension with elevated CVP is suggestive of
Cardiopulmonary problem
CVP does NOT indicate Tissue perfusion
PULMONARY ARTERY CATHETER
Swan Ganz catheter measure PCWP, mixed venous oxygen saturation, Right atrial
pressure
While introducing Swan Ganz catheter, its placement in
pulmonary artery can be identified by
PA pressure tracing has dicrotic notch from closure of
pulmonary valve > diastolic pressure is higher in PA
than in RV
Swan Ganz catheter is used to measure Pulmonary artery pressure, pressure of
cardiac chambers, pulmonary capillary
wedge pressure, cardiac output and
cardiac index, blood sample for mixed
venous oxygen saturation, to measure
temperature of pulmonary artery
Pulmonary wedge pressure is indirectly Left atrial pressure
Measurement of intravascular pressure by pulmonary
artery catheter
At the end of expiration
Left atrial filling pressure closely
resembles
Pulmonary capillary wedge pressure

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11ANESTHETIC COMPLICATIONS
CAPNOGRAM
Capnography is based on Luft principle
NOT a cardiovascular monitoring technique Capnogram
Flat capnogram Disconnection of anesthetic tubing, accidental
extubation, mechanical ventilation failure
Phases of capnogram Phase 0 – inspiratory phase, phase 1 – dead
space and little or no CO2, phase 2 –
mixture of alveolar and dead space gas,
phase 3 – alveolar plateau with peak
representing end expiratory and end tidal
CO2
ANESTHETIC COMPLICATIONS
AIR EMBOLISM
End tidal CO2 decreased during surgery Air embolism
Significant air embolism occurs with volume 100 cc
Diagnosing air embolism with tracheoesophageal
echocardiography
Very sensitive investigation, continuous monitoring to
detect venous embolism, interferes with Doppler when
used together
Factors favoring embolism is a patient with major
trauma
Mobility of fracture, diabetes
Air embolism in neurosurgery is maximum in Sitting position
Most sensitive investigation for air embolism Transesophageal echo > Doppler ultrasound
Known case of thyrotoxicosis posted for
abdominoperineal resection. sudden drop in BP and
end tidal CO2, Mill Wheel murmur
Air embolism
Most serious complication of sitting position Air embolism
Transesophageal echocardiography Can quantify the volume of air embolised, Very
sensitive investigation, Continuous monitoring is
needed to detect venous embolism
RESPIRATORY COMPLICATIONS
Anesthetic complication with respiratory infection Bacteremia, Increased mucosal bleeding, laryngospasm
Aspiration pneumonitis Affected by volume of aspiration and pH of aspiration
fluid, increased incidence during induction,
inflammation, infection
Obstruction of respiration in comatose patients is
mainly due to
Falling back of tongue
NOT a cause of respiratory insufficiency in immediate
post operative period
Mild hypovolemia