This document provides information about laryngoscopy and different types of laryngoscopes. It begins with an introduction to laryngoscopy and its uses such as endotracheal intubation. It then discusses the history and development of laryngoscopes. The document outlines the different parts of a direct rigid laryngoscope and various blade types including the Macintosh and Miller blades. It also discusses techniques for laryngoscopy and managing a difficult airway. Finally, it covers video laryngoscopy and the use of flexible fiberoptic endoscopes for intubation.

1. LARYNGOCOPE
Dr Sandeep Singh Jadon
MBBS MD Anaesthesiology
Gajraraja Medical College
Gwalior

2. INTRODUCTION
• A device used to visualise the larynx and adjacent
structures – mainly for inserting a tube into the
tracheobronchial tree

3. HISTORY
• The first laryngoscope was invented by Manuel
Garcia in 1854
• Alfred Kirsten developed direct vision laryngoscope
in 1895
• Later popularised by Sir Robert Macintosh and Sir
Ivan Magill in early 1940

4. LARYNGOSCOPY
• A procedure in which the larynx is visualized
• Useful for diagnostic , therapeutic and intubation
purposed by various specialists

5. View of larynx

6. USES
• Endotracheal intubation
• Insertion of Nasogastric tube and trans oesophageal
echo cardiac probe
• Foreign body removal
• Upper airway lesion biopsy
• visualising and assessing upper airway ( vocal cords
and larynx)

7. TYPES OF LARYNGOSCOPES
• Direct Rigid Laryngoscopes
• Indirect Rigid Laryngoscopes which uses Fiber optic,
prisms, mirrors etc.
• Video laryngoscopes– rigid and flexible
• Flexible Fiber optic Endoscopes

8. DIRECT RIGID LARYNGOSCOPE
• Dominant modality since 1940s
• Advantage: quick to use, economical, rugged,
universally available
• Disadvantage: alignment of visual, oral and
pharyngeal axis is needed

9. PARTS OF LAYNGOSCOPE
• Handle
• Blade -
• Hook on(hinged,folding)
connection between handle and
blade
• Base
• Heel
• Tongue(Spatula)
• Flange
• Web
• Tip(beak)
• Light source
bulb

10. HANDLE
• Held in hand during use
• Provides the power for light
• Accepts blade that have a light bulb to have a
metallic contact, which completes the circuit when
the handle and blade are in working position
• Handles containing batteries or using fiber optic
illumination, contain a halogen lamp bulb
• Available in several sizes , and have a rough surface
for grip

11. SHORT HANDLE:
• Used when:
• Chest or breast tissue contact the hand during use
• Cricoid pressure is being applied

12. Patil –Syracuse Handle
• Can be positioned and locked in four different
positioned

13. Blade

14. Blade
• Base:
• Attaches to handle
• Slot for engaging the hinge pin of the handle
• End of the base is called the heel
• Tongue:
• is the main shaft
• Compress and manipulate the soft tissues (esp the
tongue) and lower jaw

15. Blade
• Flange:
• Projects off the side of the tongue and is connected to
the tongue by web
• Guide instrumentation and deflect tissues from the line
of vision
• Determines the cross-sectional shape of the blade
• Tip:
• Contacts either the epiglottis or the vallecula and directly
or indirectly elevates the epiglottis
• Tip is thickened &transversely beaded to minimise
mucosal damage

16. Types of Blades
• MACINTOSH(Curved)
• Most popular, the tongue has gentle curve that
extends to the tip
• In cross section, the tongue, web and flange form
reverse Z
• It is positioned in the vallecula ant. To the epiglottis
lifting it out of the visual pathway
• Sizes ranges from 1-4,
• The no.4 blade may be more useful than no.3 in
normal and large sized adults

17. MACINTOSH(CURVED)

18. MACINTOSH(CURVED)

19. MODIFICATIONS OF MACINTOSH
• Left handed Macintosh Blade
• English Macintosh
• Polio Blade
• Improved Vision Macintosh Blade
• Oxiport Macintosh(Mac/Port)
• Tull Macintosh
• Fink Blade
• Bizzari-Giuffrida Blade
• Upscher Low Profile Blade
• Blechman Blade
• Flexible-tip Blade

20. MILLER(STRAIGHT)
• The tongue is straight with a slight upward curve
near the tip
• The flange , web, and tongue form C with the top
flattened
• It is positioned posterior to the epiglottis, trapping it
while exposing the vocal cords and glottis
• Size ranges from 0-4

21. MILLER BLADE

23. Modification of MILLER Blade
• Oxiport Miller Blade
• Tull Miller Blade
• Mathews Blade
• Winconsin Blade
• Wis-Hipple Blade
• Schapira Blade
• Alberts Blade
• Michaels Blade
• Soper Blade
• Heine Blade
• Snow Blade
• Flagg Blade
• Guedel Blade
• Robertshaw Blade
• Oxford infant Blade
• Bianton Blade
• Double- angle Blade
• Belscope Blade
• Cranwall Blade
• CW Blade
• Flexible –tip Blade
Racz-Allen Blade

24. SIZES OF BLADES FOR PEDIATRIC
PATIENTS
CHILD’S WEIGHT(KG) LARYNGOSCOPE BLADE
0-3 Miller 0
3-5 Miller 0,1
5-12 Miller 1
12-20 Macintosh 2,
20-30 Macintosh 2, Miller 2
>30 Macintosh 2, Miller 2

25. Preparation for Laryngoscopy
• Arrange proper functioning equipment-
• Suction –central, mobile, manual
• Oxygen- low and high flows
• Airway equipments- Laryngoscope, ET tube, airway, stylet,
reservoir or self inflating bag
• Patient position- sniffing
• Monitor –pulse oximeter, Ecg
• Esophageal detection device- capnograph, CO2 detector
device
• Height of operating table at the level of laryngoscopist’s navel
• Never crouch or be too close to the patient

26. Techniques of Laryngoscopy
• Position:
• Optimal sniffing position
• 25-35 degree flexion of lower cervical spine
and 85-90 degree head extension at atlanto-
occipital joint using pillow of 8-10cm height
under head. No head elevation required in
children in children <8yrs, as the their large
head circumference produces neck flexion as
the head extended at a-o Joint

27. continued…
• Laryngoscope held in left hand at the junction of handle & blade
• Optimum opening of mouth with a thumb -over-index-finger
(scissoring action) approach by right hand
• Introduce the blade into the mouth from right side without
engaging lips and teeth
• As half of blade enters the oral cavity sweeps the tongue to the left
• Advance the blade along the side of tongue towards the right
tonsillar fossa, when fossa is visualized, blade tip is moved to
midline
• Advancing blade behind the base of tongue, elevating it, epiglottis
comes into view
• From here- two different techniques for curved and straight blades

28. For Curved Blade
• Blade is advanced until
blade tip fits into the
vallecula
• Traction applied along the
axis of the handle moves
the base of tongue &
epiglottis forward and
glottis comes into view

29. For Straight Blade
• Blade is advanced
• Epiglottis identified
• The blade tip is passed
post. to epiglottis
• Blade is lifted ant.
elevating the epiglottis
directly and glottis comes
into view

30. Continued…
• Traction force (upward lifting force) should be along the
laryngoscope handle & approx 25-40 Newtons
• In difficult laryngoscopy it can be upto 50-70 N
• Never use the blade as lever and teeth as fulcrum, this
can lead to damage to maxillary teeth
• Infants and neonates: have large head ,tongue , small
oral cavity; epiglottis narrow, floppy ,long, Ushaped,
angled backwards at 45degree to tracheal axis;
• Larynx at C3-C4 level, forms acute angle with base of
tongue, difficult to see. Therefore Straight( Miller) blade
designed to pass beyond the large floppy epiglottis and
elevate it directly, known as JACKSON Position

31. Manoeuvres to improve
Laryngoscopic View
• Sometimes larynx is not visulaised even after correct
technique, then
• BURP Manoeuver- external Backward, Upward,
Rightward Pressure on thyroid cartilage may improve
visualisation of glottis
• OLEM (Optimum External Laryngeal Manipulation)

32. Mc–Coy (flexible tip blades)
• Hinged tip that is controlled by a
lever attached to the proximal end of
the blade
• When the lever is pushed toward the
handle, the tip of blade is flexed
• Some points:
• Tilting tip for elevation of epiglottis
• Increased view of larynx
• Less force required to intubate
• Unique design
• Less risk of trauma
• Ideal for difficult intubations

33. VIDEO LARYNGOSCOPES
• A new generation method of laryngoscopy and tracheal intubation. In this
the images from distal end of the laryngoscope blade are carried on to the
screen, which is either attached to the handle or carried to it by optical
cable.
• There is superior visualisation of the glottic structures,
• Aid in tracheal intubations with difficult airway
• Opertaor and assistant can see the same view and coordinate better
• Also enhance laryngoscopy teaching to beginners.
• These are:
• Mc Grath video laryngoscope
• Truview PCD laryngoscope
• Glideoscope laryngoscope video system
• C-Mac video laryngoscope
• Pentax –AWS video laryngoscope
• King Vision video laryngoscope
• Berci –Kaplan DCI video laryngoscope system

34. Steps during video laryngoscopy

35. Glide scope
• It incorporates a high resolution
digital camera, connected by a video
cable to high resolution LCD monitor
• Embedded anti fogging mechanism
• used for difficult airway intubations,
for removal of foreign bodies from
airways
• Comes in three models: standard;
paediatric ; neonatal version to suit
all ages
• Has a steep 60 degree angulation,
reduced overall thickness of 14mm
of its blade improves the view of
glottis
• Latest version COBALT uses
disposable blade

36. MC GRATH VIDEOLARYNGOSCPE
• Videoscope with built in screen
• Blade similar to Glidescope
• Plastic sheath for blade
• Blade adjustable , only
laryngoscope with a feature if
variable blade length
• Depth of blade 13mm easy for
patients with limited mouth
opening
• Low cost, single use blade,
reduced sterilisation time

37. TRUEVIEW PCD LARYNGOSCOPE
• Functions both as optical and videolaryngoscope
• Can be attached to any other monitor with a CCD camera head
• Provide clear enlarged view that enhance ease of tracheal
intubation
• Oxygen flow via side channel on handle provides continous
oxygenation- dealys desaturation and prevents fogging of lens
and clear sectetions in its path
• 5 blade sizes- from neonates to adults
• Best suited for patients with limited mouth opening,
micrognathia, collar in place

38. PENTAX AIRWAY SCOPE
• Consist of disposable
transparent blade, 12cm cable
with charged coupled
device(CCD) and 2.4inch LCD
• Blade has channel for
suction/oxygenation; cable
• Blade is anatomically shaped
and tube is premounted on it
and CCD cameras is 3cm
proximal from tip of blade
• Provide good view of glottis
and adjacent structures

39. C-MAC VIDEOLARYNGOSCOPE
• 4th gen video laryngoscope by Karl
Storez
• Clear image without fogging
• Record still images and video
sequences on SD memory card
• Blade flattened and round edges
so useful in case of reduced oral
aperature and less damage to
teeth and soft tissues
• Available in 4 sizes(1-4)
• D-blade (Dorges) for difficult
airway , with angulation of >60
degree, comes in only one adult
size

40. King vision
• A durable , fully portable
digital video laryngoscope
• Device has high quality
reusable display and
disposable blades
• Comes in 2 versions:
• Channeled- allows Ets 6.0-8.0
• Non Channeled
• Has antifogging coat on lens
preventing blurring of view

41. FLEXIBLE FIBER OPTIC ENDOSCOPE
• Dr Peter Murphy was the first to use flexible fiberscope to
perform tracheal intubation in 1967
• Device description:
• Light source
• Handle
• Eyepiece
• Focussing ring
• Working channel ports
• Tip control lever
• Insertion cord
• Universal cord for light transmission

43. Fiber optic intubation
• It can be performed
awake or in
anaesthetised patient.
• Indications:
Where there is known or
suspected difficulty with
mask ventilation or
tracheal intubation

44. • Contraindications
• “critical airway” = a patient with stridor has an airway that
become obstructed with minimal provocation

46. Approach
• Oral or nasal approach:
• Nasal is preferred, - due to-
easier line of access to larynx,
better tolerated
• Oral approach- though mouth
has greater volume, but easier
to stray away from midline, so a
split oral airway i.e., Berman or
Ovassapian is used

47. Preparation: Equipment
• An Anaesthetic machine
• Suction
• Emergency drugs
• Monitors- Ecg, NIBP, Pulse oximeter, capnograph(EtCo2)
• Nasopharyngeal airways
• Fiberoscope:
• Operator to set the scope and monitor.
• Following steps are followed:

49. Preparation of patient
• Explain the procedure to the patient
• Full monitoring to be applied before starting the procedure.
• Antisailogogues:
• Inj Glycopyrrolate 4-8mcg/kg given I.M (more effective im as
compared to iv in anaesthic room) an hour before intubation,
• dries mucus membranes, which both increases the efficacy of
topical anesthesia, and improves intubating conditions by
decreasing secretions
• Patient and operator position:

50. • Oxygen delivery:
• Important as sedation is given to the patient.
• Devices such as single nasal prongs, a nasal sponge or Hudson
mask (non rebreathable mask) cut appropriately to allow
access to nostril of patient
• Sedation:
• Conscious sedation is desirable. Along with good local
analgesia.
• The goal is to provide good analgesia and amnesia in a calm
and cooperative patient , following verbal commands, while
maintaining patent airway, adequate oxygenation and
ventilation

52. • Local anaesthesia of the airway:
• Vasoconstrictors:
• Its addition ( e.g. epinephrine 0.1%, phenylephrine0.5%-1%,
xylometazoline 0.05%) 1-2 drops in each nostril,
• decreases local blood flow, slows the rate of absorption of LA and
prolongs its effect
• Its recommended that the conc. Of epinephrine should not be
more than 1:200 000
• A combination of vasoconstrictor plus local anaesthetic can be
used e.g.(Co-Phenylcaine (50mg/ml lidocaine, 5mg,ml
phenylephrine)
• Maximum topical safe dose of lidocaine to be used upto 9mg/kg
for airway mucosa
• Anaesthetising the nasopharynx:
• The trigeminal nerve provides the sensory fiberes to nasal
mucosa, which also innervates the superior segment of tonsils,
uvula, pharynx

53. • Different techniques available to anaesthetise the nose.
• Best is Co-Phenylcaine f/b Instillagel (2% lignocaone and chlorhexidine) to
the nares
• Others- 4% cocaine soaked cotton swabs
• Nebulised 4% lidocaine (4-6)ml
• ‘Moffets’ solution which is 1ml 1:1000 epinephrine , 2ml 1% sodium
bicarbonate and 2ml 10% cocaine
• Anaesthetising the oropharynx:
• Pharynx and post. Third of tongue is innervated by glossopharyngeal nerve
• Mucosal atomiser devices(MAD) useful to assist in depositing
• The local anaesthetic as fine droplets.

55. • A benzocaine lozenge may be used to start the process
• Instillagel can be gargled orally to anaesthetise the pharynx,
f/b 1% and 4% lidocaine spray
• Anaesthetising the larynx:
• Vagus supplies sensory branches both above and below vocal
cords via two main branches.
• The sup. Laryngeal nerve- supplies arytenoids, epiglottis,
sensation above vocal cords;
• Recurrent Laryngeal nerve- below vocal cords
• The commenest method to anaesthetise larynx is to spray
lignocaine directly down the fiberscope side port (Spray-as-
you-go technique)
• 2ml of 4% lox with air is injected via sideport forcefully on-
epiglottis, above the cords, below the cords, the trachea;
• Whenever it is given cough reflex occurs, therefore to wait
until the view clears.

56. • Other techniques:

59. Bronchoscopy and intubation:
• Operator passes the scope thru nose under direct vision
• Scope should be held taught and straight
• Small movements od the tip of scope tend to allow the most
successful manoeuvring through the airway
• As epiglottis and cords are visualised the spray-as-you-go technique
is instigated
• Ask pt to take deep breath facilitates entery of scope through cords
• Through the cords advance the tip of scope till a reasonable
distance
• ETTube is railroaded in a twisting motion after applying lubrication
on nares with lignocaine jelly and to the cuff of the tube.
• If resistance is met, it is likely that tube tip has caught on the
arytenoids
• A 360 degrees continual rotation shouls overcome this

60. • Advance the ETT into the trachea over the scope until tip of
tube is correctly positioned above the carina.
• Withdraw fiberscope and attach the circuit to ETT, fix and
check to b/l equal air entry
• Capnography will confirm the correct placement and general
anaesthesia can be induced (iv/inhalational)

61. Complications

62. Continued
• Used to:
• Place and evaluate placement of tracheal, double lumen ,
tracheostomy, and gastric tubes and bronchial blockers
• Check tube patency,
• Evaluate airway
• Locate and remove secretions
• Advantages:
• Laryngoscopic intubation can be done via nasal route also
• In restricted neck movements and mouth opening
• To overcome Anatomical variations
• Good view of glottis, larynx, trachea

63. • Disadvantages
• Delicate instrument and needs extra care
• High cost
• Learning curve , needs practice
• Tissue oedema and blood can obscure vision
• Cleaning/ sterlization takes time

69. Thank you.