for revision

1. AIRWAY MANAGEMENT
PRESENTER:DR.ANNA

2. Outline
• Anatomy of the Human Airway
• Airway Assessment
• Perioperative Airway Management Techniques
• Endotracheal intubation
• Complications of Laryngoscopy and ETT
• Management of DA
• Patient with cervical injury
• Reference

3. Anatomy Of the Human Airway
• Knowledge of the human airway anatomy is important to safe and
efficient airway management.
• The upperairway consists of the passages from the nose and mouth
to the larynx.
• The lowerairway includes structures distal to the glottis.

5. The Nasal Cavity
• The nasal cavity provides for the passage,filtration, humidification,
and warming of inhaled air

6. Oral Cavity
• The mouth includes the dentition,anterior two-thirds of the tongue,
floor of the mouth, and undersurface of the hard and soft palates.
• The anterior tonsillitis pillars/ pallatoglossal folds mark the division
between the oral cavity and the oropharynx
• The tongue continues posteriorly into the pharynx and is attached to
the epiglottis by mucosa.

7. The Pharynx
• Is a U-shaped fibromuscular tube that, anatomically and functionally,
is divided into three areas:
• Nasopharynx,is posterior to the nasal cavity and serves as an air
conduit.
• Oropharynx is the main passage of the aerodigestive tract
• Hypopharynx, the continuation of aerodigestive tract ,extends from
the epiglottis to the lower border of the criccoid cartilage it’s
contiguous with the esophagus.
• The larynx bulges posteriorly into the hypopharynx thus creating
lateral recesses on either side called pyriform recesses.

8. The Larynx
• It lies at the level of the third to the sixth cervical vertebrae, anterior
to hypopharynx
• Functionally it’s organ of phonation and the passageway for air into
the trachea and lungs.
• The airway is protected by epiglottis from contamination from the
alimentary tract
• It consists of a cartilaginous skeleton bound by ligaments,mem-
branes,and muscles.

9. • The cartilaginous skeleton of the larynx consists of
• three unpaired cartilages – the epiglottis, thyroid, and cricoid, and
• three paired cartilages – the arytenoid, cuneiform, and corniculate.
• The epiglottis is the functional division between the oropharynx and
larynx.
• The cricoid cartilage is signet ring–shaped and is the only complete
cartilaginous ring in the airway.
• Vocal cords are formed from cricothyroid ligaments.

10. • Superior and recurrent laryngeal nerves supply all motor and sensory
innervations of the larynx
• The larynx is designed for phonation and protection of the airway.
• The muscles that perform these functions are divided into external
and internal groups.
• The external group controls position and movement of the entire
larynx.
• The internal group provides for delicate movements that affect glotic
opening..

11. • Cricothyroid muscle lies external to the larynx,acts to provide tension
to the vocal cords (adductor).
• The recurrent laryngeal nerve supplies all motor function to the
internal laryngeal muscles whereas the cricothyroid muscle is
supplied by the external branch of the superior laryngeal nerve.

12. Trachea
• It is a tubular structure that begins at the inferior border of the
cricoid cartilage at the level of the sixth cervical vertebra.
• It consists of 16 to 20 C-shaped hyaline cartilaginous rings
• Connected posteriorly by the membranous trachea.
• The adult trachea is approximately 12 mm in diameter and 9 to 15
cm in length
• It bifurcates into the left and right mainstem bronchi at the carina

13. • The bronchi into lobes and finally forms alveoli
• Air continues through the bronchioles to the alveoli where gaseous
exchange occurs

14. Airway Assessment
• Before anesthetizing ANY patient, we examine the airway,
looking for physical findings that can be reassuring or
worrisome.
• The following steps help us to assess problems that might arise
during laryngoscopy:
-Assess mouth opening: inter-incisor distance should exceed 4 cm
in an adult.
-Determine the mentum–hyoid (>4 cm) or thyromental (>7 cm)
distance: shorter distances suggest an “anterior” or very cephalad
larynx, which would be difficult to visualize by conventional
laryngoscopy.

15. Airway Examination
• Mallampati score
• Upper lip bite test (Teeth and bite) Ability to protrude lower incisors beyond
upper
• Inter-incisor distance (Mouth opening)
• Thyro-mental distance > 6.5cm
• Sterno-mental distance > 12.5cm
• Cormark and Lehane score
• Length & thickness of neck
• Range of motion of head & neck
• Facial hair
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16. Mallampati classification
• Class I = visualize the soft palate, uvula,
anterior and posterior pillars.
• Class II = visualize the soft palate and
uvula.
• Class III = visualize the soft palate and the
base of the uvula.
• Class IV = soft palate is not visible at all.
• Upright,
• maximal jaw opening,
• tongue protrusion without
phonation

17. ULBT (Teeth and Bite)
• Class 1:
Lower incisors can bite upper lip
above vermillion line.
• Class 2:
Lower incisors can bite upper lip
below vermillion line.
• Class 3:
Lower incisors cannot bite the upper lip.
17

18. Inter-incisor distance
Less than or equal to 4.5 cm is
considered a potentially
difficult intubation.
 Generally greater than 2.5 to 3
fingerbreadths (depending
on observers fingers)

19. Thyro-mental distance (TMD)
• Upright
• Full neck extension
• Mouth closed
• Distance from upper boarder of
thyroid cartilage (laryngeal
prominence), to the boney point
of the mentum.
• Distance < 6.5cm may be
difficult intubation

20. Sterno-mental Distance (SMD)
• Extended head and neck,
• mouth closed,
• distance <12.5cm is a difficult
intubation

21. CRANIOFACIAL DEFORMITIES
Pierre Robin Goldenhar's
Treacher Collins
21

22. Why would this man’s airway
be difficult to manage?
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23. Independent Predictors of Difficult Mask Ventilation and Intubation
Difficult Mask Ventilation P-value
Beard 0.0001
History of snoring 0.001
BMI > 30 0.0001
Mallampati III or IV 0.001
Age > 50 0.01
Severely limited jaw protrusion 0.03
Difficult Mask Ventilation & Intubation
Severely limited jaw protrusion 0.0001
Thick neck/mass 0.02
History of sleep apnoea 0.04
BMI > 30 0.05
History of snoring 0.05
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24. Physical Examination - Risk Factors for Difficult Intubation
Risk Factor Detail Level of Risk
Weight < 90 kg 0
90-110 kg 1
> 110 kg 2
Head & Neck Movement > 90 o 0
Approx 90 o 1
< 90 o 2
Jaw movement
IG = Interincisor gap
Slux = mandibular subluxation
IG > 5 cm or Slux > 0 0
IG < 5 cm or Slux = 0 1
IG < 5 cm or Slux < 0 2
Receding Mandible Normal 0
Moderate 1
Severe 2
Protruding maxillary teeth Normal 0
Moderate 1
Severe 2
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25. Cormack & Lehane Score
1 2
3 4
25

26. Mallampati Classification
• Investigate the posterior pharynx by modified Mallampati
classification
• The test is done as the patient sits with the head in a neutral position,
the mouth open,and the tongue protruding to its limit

27. Evaluate neck mobility:Atlanto-occipital joint extension
• The“sniffing position” to help align a patient’s head during tracheal
intubation, requires some degree of neck mobility
• Ingeneral,neck extension 35° is associated with difficulty in intubation; the
average neck extension is 54 °to 64°
• History of Difficult Intubation and Any Obvious Airway Pathology

28. Dentition
• Prominent teeth may hinder direct laryngoscopy by limiting the
alignment of the oral and pharyngeal axis during laryngoscopy
• An edentulous state may cause hypopharyngeal obstruction by the
tongue during bag–mask ventilation.
• Risk factors for dental injury and difficult laryngoscopy include
prominent upper incisors or canines or an overbite.

29. Periopetative Airway Management
Techniques
• Bag-Mask Ventilation
• This is essential airway management technique that needs to be
practiced and learned by every healthcare provider.

30. Proper Mask Techniques
• -Select an appropriate size mask to cover the patient’s nose and
mouth and provide an airtight seal without pressure on the eyes.
• -Place the head in snifing position (occiput elevated, neck extended)
or directly supine, with the neck neutral to slightly extended.
-Positioning yourself at the patient’s head, apply the mask to the face
with a pincer grip by thumb and index finger of the left hand. Place the
third finger on the mentum and pull the chin upward.
• The fourth nger remains on the mandible, not the so tissue under the
jaw where it might cause compression and obstruction. With the
pinkie at the angle of the mandible, pull the jaw forward to open the
posterior pharynx (a painful maneuver in an awake patient!)

31. -Then, ventilate the patient’s lungs with a self inflating bag,
Mapleson or anesthesia machine circle system.
Whenever mask ventilation is used, no more than 15 to 20 mm Hg of
positive pressure should be required, unless pulmonary pathology or
obesity is present.
Applying higher pressure may lead to gastric insufflation, compromise
of oxygenation, regurgitation, and/or aspiration

32. Difficult Bag-Mask: What To Do?
Difficulty with mask ventilation is encountered in elderly, obese,
edentulous, or bearded patients, as well as in patients with a history of
obstructive sleep apnea
Reposition. Make sure the mandible is being pulled anteriorly.
Add a second person to try two-handed mask ventilation. One
person uses both hands to hold the mask and pull the jaw
anteriorly;the other compresses the breathing bag.
Use an oral or nasal airway to establish a pathway past the
pharyngeal tissue and tongue.

33. Supraglotic Devices
• Supraglottic devices are designed to keep the airway patent without
entering the larynx.
• The most commonly used is LMA
• Recently Combitube and the King Laryngeal tube have been used
increasingly.

34. Indications
• They are indicated for nonemergent anesthetic cases, in healthy
patients without the risk of aspiration,and for routine,short
procedures (ASA I and II)
• Outside these indications, they may be used for rescue when
tracheal intubation fails or is not available.
• Contraindications
• Not fasted patients
• Women in labor
• Poor pulmonary compliance

35. • Any patient with risk ofpulmonaryaspiration,hiatal hernia with
significant postional GERD, oropharyngeal, glottic or subglottic airway
obstruction;
• Limited mouth opening.

36. Laryngeal Mask Airway (LMA)
• LMA is composed of an airway tube with a standard 15-mm
anesthetic connector at the proximal end and an inflatable mask at
the distal end.
• In the hypopharynx with the opening overlying the laryngeal entrance
and the tip of the mask within the upper esophageal sphincter.
• It can be used for spontaneous or postive pressure (20mm
HO2)ventilation when correctly placed
• Protects the airway from secretion but not from regurgitation

37. • (i)Place the patient’s head in the sniffing position;
• (ii) stabilize the occiput and slightly extend the neck with the
right hand, allowing the jaw to fall open;
• (iii) press the deflated LMA against the hard palate with the
gloved index finger, and gently advance it until encountering the
resistance of the upper esophageal sphincter.

38. Endotracheal Intubation
• It provides a means for airway patency and protection, mechanical
ventilation, and protect against gastric contents aspirations.
• Primary surgical indications
• prevention of loss of the airway, complicated cases (requiring a
signicant proportion of time to be focused on nonairway tasks),
• unusual positioning for surgery,
• cases in which high airway pressures may occur,
• gas exchange is likely to be impaired.

39. • Primary patient indications
• Airway protection,
• The need for close control of end-tidal CO2,and
postoperative intubation
• Secondary indication is when surgical or anaesthetic complications
occurs such high spinal,massive haemorrhage,MH,or inadequate
regional anaesthesia

40. • Orotracheal intubation is the commonest route of intubation for
general anesthesia and cardiopulmonary resuscitation.
• Nasotracheal approach is reserved for surgical procedures requiring
free access to the oropharynx or for patients with limited access to
the oral cavity.

41. Endotracheal Tubes
• Standard ETTs are made of polyvinyl chloride and shaped to follow
the contour of the airway
• Shape and rigidity can be altered by inserting a sytlet
• There is a lateral opening at the proximal end (Murphy’s eye) to
prevent occlusion
• Wire –reinforced flexible ETTs (armored) are available too
• Armored tubes are resistant to kinking and occlusion.
• They are preferred for use in neck and head surgery

42. • Some ETTs are cuffed to ensure proper tracheal seal
• The cuffs can be high pressure(low volume ) or low pressure (high
volume)
• High pressure cuffs can cause mucosal ischaemia after prolonged use
• Low pressure cuffs can cause sore throat and weak airway protection

43. ETT size
• For an adult male, about a size 8.0 (internal diameter in millimeters) is
preferable, whereas about a size 7.0 is preferred for an adult female
• In children,ETT size can be calculated by the formula 4 +age/4
• Uncuffed ETTs generally are used for children 5years old.

44. Laryngoscope
• Commonly used are Macintosh(curved) and Miller (straight )
blades
• The Miller blade is more advantageous in patients with a small
mandibular space, large incisors, or a large epiglottis, whereas
the Macintosh blade may be better for patients with a small
mouth.

46. Necessary Equipment for Oral Tracheal
Intubation
• Properly checked anesthesia machine, or a selfinating bag or
Mapleson system with source of compressed oxygen, and a tight-
fiyting mask;
• endotracheal tubes (ETT) of appropriate sizes
• a stylet that ts in the ETT – sometimes required to stiffen and
shape the tube;
• a syringe to inflate the ETT cuff;
• an oral airway, in case intubation and mask ventilation prove to
be difficult;

47. • laryngoscope handle and appropriate blades , usually at least a
curved (Macintosh) and straight (Miller), with confirmation that
the light works!
• suction apparatus – for the inevitable oral secretions and
potential regurgitation;
• induction drugs;
• An assistant schooled in application of cricoid pressure

48. • After the patient has been postioned, denitroginated,and induced
proceed as follows to intubate.
• Take the laryngoscope in your le hand; the right hand is
responsible for everything else
• Place the right hand on top of the patient’s head and
accentuate neck extension. Note that some prefer to perform a
scissor-like maneuver with the right thumb and index nger to
open the patient’s jaw.

49. • Advance the laryngoscope down the right side of the mouth to the
level of the tonsillar pillars. Sweep the tongue to the le as you bring
the laryngoscope to the midline
• With a straight blade, lift the epiglottis; with a curved blade, place it
in the vallecula (at the base of the epiglottis). As above, lift forward
and upward (along the axis of the laryngoscope handle)
• When you can see the glottic opening clearly, grasp the endotracheal tube
(hold it like a pencil – not a dagger) with the right hand (preferably without
losing sight of the glottis), and advance the tip into the trachea just until
the cu disappears completely beyond the vocal cords.

50. • Inflate the cuff only to the point of no air leakage, and confirm
tracheal position.

51. How to Confirm Tracheal Position
• Confirmation of exhaled CO2 by capnography
• Breath sounds. While not definitive for tracheal placement, breath
sounds should be present across the chest and absent over the
stomach.
• Condensation
• Palpation of the ETT cuff
• Symmetrical chest excursion

52. Complications Of Laryngoscopy and
Endotracheal Intubation
• (1)airway trauma (damage to teeth, lips, tongue, pharynx, vocal
cords, arytenoid cartilages, or trachea),
• (2) physiologic responses to airway manipulation(hypertension,
tachycardia, increase in ocular or intracranial pressure,
laryngospasm),
• (3) tube malposition (esophageal or endobronchial placement,
unintentional extubation), and
• (4) tube malfunction (cuff perforation, ignition, and obstruction).

53. Management of Difficult Airway
• Definition
• Is the clinical situation in which a conventionally trained
anesthesiologist experiences difficulty with face mask ventilation of
the upper airway, difficulty with tracheal intubation, or both
• OR
• An intubation requiring more than three attempts at laryngoscopy or
taking longer than ten minutes.

54. Difficult Airway Alogarithm

55. Alternative airway devices and techniques
• If the clinician encounters the cannot-intubate/cannot ventilate
situation, it is imperative to consider
• (1) calling for help,
• (2) returning to spontaneous ventilation, and/or
• (3) awakening the patient.

56. • Continue with ventilation only when ventilation is possible
• Blind Intubation (usually successful when done through the nose)
• LMA insertion
• Combitube or King Airway
• Lighted stylet (a lighted malleable stylet inside an ETT used to
identify the trachea by a pretracheal glow in the neck)
• Fiberoptic intubation (with or without LMA as a conduit)

57. • Intubating stylet or airway exchange catheter
• Retrograde intubation (a wire placed via the cricothyroid
membrane is advanced into the nose or mouth, then used as a
guide for intubation) – not all that non-invasive and not routinely
successful

58. Invasive rescue techniques
• Cricothyrotomy (with a needle and jet ventilation)
• Percutaneous tracheostomy (possible in a minute)
• Surgical tracheostomy (takes many minutes)

59. Patient with Cervical Spine Injury
• An asleep airway technique. One that does not require neck
movement, such as intubating through an LMA, using a video-
laryngoscope (Glidescope, AirTraq, and others), lighted stylet, or
retrograde intubation.
• In skilled hands, these techniques may be performed with
relative speed.
• A lengthy process increases the likelihood of aspiration.

60. • Awake fiberoptic intubation.
• May be difficult and even dangerous to an at-risk cervical spinal
cord in an intoxicated, uncooperative patient, and may take too
long in the patient with multiple traumatic injuries.

61. • Blind Nasal Intubation
• Again, skilled hands dramatically increase the likelihood of
success,
• It is contraindicated in the presence of a base-of-skull fracture,
e.g., with “raccoon eyes” or with cerebrospinal fluid dripping from
the nose, as the endotracheal tube could enter the brain via the
fracture site

62. • Direct laryngoscopy with in-line stabilization.
• A second person stabilizes the neck (without pulling on the
head) in an effort to minimize neck extension.

63. • Awake tracheostomy.
• Far more invasive than the other techniques, we reserve this
primarily for patients with upper-airway trauma that will prevent
other intubation techniques.

64. Reference
• Miller Anaesthesia 7th ed
• Morgan & Mikhail’s Clinical anaesthesia 5th Ed
• James Duke, Brian Keech-Duke's Anesthesia Secrets-Saunders (2015)

65. The Intubator