This document provides an overview of airway management, including anatomy of the airway, evaluation of the airway, basic airway techniques, indications for intubation, and equipment for airway management. It also discusses the difficult airway algorithm. Key topics covered include anatomy of structures in the airway, tests for evaluating the airway, maneuvers for opening the airway, indications for endotracheal intubation, laryngoscopy technique, and equipment such as laryngoscopes, endotracheal tubes, masks, and airway adjuncts. The difficult airway is defined as one where mask ventilation or intubation is difficult for an anesthesiologist.

1. AIRWAYAIRWAY
MANAGEMENTMANAGEMENT

2. OVERVIEWOVERVIEW
 Anatomy of the AirwayAnatomy of the Airway
 Evaluation of the AirwayEvaluation of the Airway
 Basic Airway ManagementBasic Airway Management
 Indications for Endotracheal IntubationIndications for Endotracheal Intubation
 Equipment for Airway ManagementEquipment for Airway Management
 Difficult Airway AlgorithmDifficult Airway Algorithm

3. Anatomy of the AirwayAnatomy of the Airway

4. Innervation of theInnervation of the
Nasopharynx and OropharynxNasopharynx and Oropharynx
CN V - Trigeminal Nerve
• V1 - Ophthalmic Division
(anterior ethmoidal n.)
• V2 - Maxillary Division
(sphenopalatine n.)
• V3 - Mandibular Division
(lingual n.)

5. Innervation of theInnervation of the
Nasopharynx and OropharynxNasopharynx and Oropharynx
CN VII – Facial Nerve
Taste to posterior 1/3 of tongue
CN IX – Glossopharyngeal Nerve
Sensation to posterior 1/3 of tongue,
tonsils, pharynx

6. Nerve Supply to the LarynxNerve Supply to the Larynx
CN XCN X – Vagus Nerve– Vagus Nerve
• Superior Laryngeal NerveSuperior Laryngeal Nerve
- Motor to cricothyroid muscle- Motor to cricothyroid muscle
- Sensory to above the vocal- Sensory to above the vocal
cordscords
• Recurrent Laryngeal NerveRecurrent Laryngeal Nerve
- Motor to all intrinsic muscles- Motor to all intrinsic muscles
exceptexcept cricothyroidcricothyroid
- Sensory to below the vocal- Sensory to below the vocal
cordscords

7. Clinical SignificanceClinical Significance
 Acute bilateral RLN injuryAcute bilateral RLN injury stridor,stridor,
respiratory distressrespiratory distress
 Need for topical anesthetics for nasalNeed for topical anesthetics for nasal
intubationintubation
 Nerve blocks for awake intubationNerve blocks for awake intubation
– Glossopharyngeal nerve blockGlossopharyngeal nerve block
– Superior laryngeal nerve blockSuperior laryngeal nerve block
– Transtracheal blockTranstracheal block

8. Anatomy of the LarynxAnatomy of the Larynx
C4-C6 levelC4-C6 level
3 single cartilages3 single cartilages
• epiglottisepiglottis
• thyroidthyroid
• cricoidcricoid
3 paired cartilages3 paired cartilages
• arytenoidsarytenoids
• corniculatescorniculates
• cuneiformscuneiforms

9. Anatomy of the LarynxAnatomy of the Larynx

10. Clinical SignificanceClinical Significance
 Cricothyroid membrane puncture duringCricothyroid membrane puncture during
cricothyrotomycricothyrotomy
 Cricoid cartilage –Cricoid cartilage – signet ring,signet ring, Sellick’sSellick’s
maneuvermaneuver

11. Anatomy of the AirwayAnatomy of the Airway
 TracheaTrachea
– 15 cm long ( adult)15 cm long ( adult)
– 16-20 C shaped16-20 C shaped
cartilagescartilages
– Bifurcates to R and LBifurcates to R and L
bronchus at T5bronchus at T5
– R bronchus appears toR bronchus appears to
be a verticalbe a vertical
continuation of tracheacontinuation of trachea
 Aspiration more commonAspiration more common
 R mainstem intubationR mainstem intubation
more commonmore common

12. Evaluation of the AirwayEvaluation of the Airway
Historical InterviewHistorical Interview
 Prior difficult intubation?Prior difficult intubation?
 Surgical history – head and neckSurgical history – head and neck
 Congenital and Acquired SyndromesCongenital and Acquired Syndromes
– Down syndrome, Pierre Robin syndrome, Ludwig’sDown syndrome, Pierre Robin syndrome, Ludwig’s
anginaangina
 Medical condition that may predisposeMedical condition that may predispose
to difficult intubationto difficult intubation
-- Morbid Obesity, TMJ dysfunction, TumorsMorbid Obesity, TMJ dysfunction, Tumors
 Review of previous anesthetic recordsReview of previous anesthetic records

13. MacroglossiaMacroglossia

14. Evaluation of the AirwayEvaluation of the Airway
Ancillary TestsAncillary Tests
 RadiographsRadiographs (cervical x-ray)(cervical x-ray)
 CT ScanCT Scan
 MRIMRI
 Pulmonary Function TestsPulmonary Function Tests
 Direct Fiber-optic ExaminationDirect Fiber-optic Examination

15. EpiglottitisEpiglottitis

16. Evaluation of the AirwayEvaluation of the Airway
Physical ExamPhysical Exam
General assessmentGeneral assessment
- cachexia, need for O2 support, cyanosis,- cachexia, need for O2 support, cyanosis,
morbid obesity, VS including SpO2morbid obesity, VS including SpO2
Focused Airway ExamFocused Airway Exam

17. MALLAMPATI CLASSIFICATIONMALLAMPATI CLASSIFICATION
I II III IVII
I II III IVCLASS
Pharyngeal pillars +
Uvula +
Soft palate +
Hard palate
P, u, S, H S, H H

18. MALLAMPATI CLASSIFICATIONMALLAMPATI CLASSIFICATION
 Patient sitting, mouth fully opened, tongue
fully extended, without phonation
 Significant interobserver variability
 Sensitivity : 60-80%
 Specificity : 53-80%

19. Thyromental DistanceThyromental Distance
estimates theestimates the
displacement ofdisplacement of
the tonguethe tongue
notch of thyroid cartilage
tip of the mandible
Normal = 6.5 cm
neck fully extended

20. Thyromental DistanceThyromental Distance
 Questioned the most re: predictive valueQuestioned the most re: predictive value
 Sensitivity : 60-80%
 Specificity : 80-90%
 Arne and El-Ganzouri : highly insensitive
but very specific (17% and 99%)
 Chou and Wu : adjust this measure to pt’sChou and Wu : adjust this measure to pt’s
heightheight

21. Mouth Opening/Incisor GapMouth Opening/Incisor Gap
< 3 cm< 3 cm – reduces– reduces
prevalence of easyprevalence of easy
intubation fromintubation from
95% to 62%95% to 62%

22. Neck MovementNeck Movement
 Neck Flexion :Neck Flexion : >80 degrees>80 degrees
 Neck Extension :Neck Extension : >90 degrees>90 degrees

23. Bell House and Dore ClassificationBell House and Dore Classification

24. Mandible ProtrusionMandible Protrusion

25. Multivariate Predictors of DifficultMultivariate Predictors of Difficult
Tracheal IntubationTracheal Intubation
 1996, El-Ganzouri1996, El-Ganzouri
 Prospective analysis of 10,507 consecutive adultProspective analysis of 10,507 consecutive adult
patients presenting for surgery under generalpatients presenting for surgery under general
anesthesiaanesthesia
 A multivariate model for stratifying the riskA multivariate model for stratifying the risk
 Compared to Mallampati Class I as a singleCompared to Mallampati Class I as a single
predictor. A risk index score of threepredictor. A risk index score of three
demonstrates a higher sensitivity (59 vs 44)demonstrates a higher sensitivity (59 vs 44)

26. Multivariate Predictors of DifficultMultivariate Predictors of Difficult
Tracheal IntubationTracheal Intubation
 Mouth openingMouth opening
 Thyromental distanceThyromental distance
 Mallampati ClassMallampati Class
 Neck MovementNeck Movement
 Ability to Protrude theAbility to Protrude the
MandibleMandible
 Body WeightBody Weight
 History of DifficultHistory of Difficult
IntubationIntubation

27. Maneuvers for Opening the AirwayManeuvers for Opening the Airway
Head Tilt orHead Tilt or
Chin LiftChin Lift

28. Maneuvers for Opening the AirwayManeuvers for Opening the Airway
JawJaw
ThrustThrust

29. Upper Airway ObstructionUpper Airway Obstruction

30. ORAL AIRWAYORAL AIRWAY

31. NASAL AIRWAYNASAL AIRWAY

32. MASK VENTILATIONMASK VENTILATION

33. INDICATIONS FOR ENDOTRACHEALINDICATIONS FOR ENDOTRACHEAL
INTUBATION (operative)INTUBATION (operative)
1.1. Need to deliver positive pressureNeed to deliver positive pressure
ventilationventilation
2.2. Protection of the respiratory tractProtection of the respiratory tract
3.3. Head, neck, chest surgeryHead, neck, chest surgery
4.4. GA in nonsupine positionGA in nonsupine position
5.5. Neuromuscular paralysis institutedNeuromuscular paralysis instituted
6.6. Need to treat intracranial HTNNeed to treat intracranial HTN
7.7. Lung isolationLung isolation

34. INDICATIONS FOR ENDOTRACHEALINDICATIONS FOR ENDOTRACHEAL
INTUBATION (non-operative)INTUBATION (non-operative)
1.1. Decreased consciousnessDecreased consciousness
2.2. Tracheobronchial toiletTracheobronchial toilet
3.3. Severe pulmonary and multi-systemSevere pulmonary and multi-system
injury associated with respiratory failureinjury associated with respiratory failure
 Severe sepsisSevere sepsis
 Airway obstructionAirway obstruction
 Hypoxemia/hypercarbia of various etiologiesHypoxemia/hypercarbia of various etiologies

35. Objective MeasuresObjective Measures
((FOR ENDOTRACHEAL INTUBATIONFOR ENDOTRACHEAL INTUBATION))
 RR > 35/minRR > 35/min
 Vital Capacity < 15 ml/kgVital Capacity < 15 ml/kg
 Inability to generate a negative inspiratory forceInability to generate a negative inspiratory force
of 20 mm Hgof 20 mm Hg
 PaO2 < 70 mm Hg on 40% FiO2PaO2 < 70 mm Hg on 40% FiO2
 A-a gradient > 350 mm Hg on 100% O2A-a gradient > 350 mm Hg on 100% O2
 PaCO2 > 55 mm HgPaCO2 > 55 mm Hg
 Dead Space (Vd/Vt) > 0.6Dead Space (Vd/Vt) > 0.6

36. LARYNGOSCOPYLARYNGOSCOPY

37. Alignment of the AxesAlignment of the Axes

38. Alignment of the AxesAlignment of the Axes
Neck Flexion

39. Alignment of the AxesAlignment of the Axes
Neck Flexion + Atlanto-Occipital Extension
“Sniffing Position”

40. Cormack - LehaneCormack - Lehane
ClassificationClassification
Entire
glottic
aperture
Posterior aspect
of glottic aperture
Tip of epiglottis
Soft palate

41. LARYNGEAL MANIPULATIONLARYNGEAL MANIPULATION
B - backward
U - upward
R - rightward
P - pressure
BURP
Maneuver

42. Equipment for Airway ManagementEquipment for Airway Management
 ORAL AIRWAYSORAL AIRWAYS
– Relieves obstructionRelieves obstruction
due to tongue fallingdue to tongue falling
backwardbackward
– Initially insertedInitially inserted
towards hard palatetowards hard palate
then rotated 180then rotated 180
degreesdegrees
– Can cause gag /vomitCan cause gag /vomit
reflexreflex
 NASAL AIRWAYSNASAL AIRWAYS

43. Equipment for Airway ManagementEquipment for Airway Management
 Anesthesia Face MaskAnesthesia Face Mask
– Should fit over the bridge ofShould fit over the bridge of
the nose cheeks and chin tothe nose cheeks and chin to
produceproduce AIRTIGHT SEALAIRTIGHT SEAL
– Increased dead spaceIncreased dead space
therefore larger TV requiredtherefore larger TV required
– Clear mask preferable to seeClear mask preferable to see
vomitus/secretions and colorvomitus/secretions and color

44. Equipment for Airway ManagementEquipment for Airway Management
 LaryngoscopesLaryngoscopes
– Consist of handle and bladeConsist of handle and blade
– Handle has the batteries.Handle has the batteries.
Usually rough for better gripUsually rough for better grip
– Blades are designed to enterBlades are designed to enter
mouth, displace the tongue,mouth, displace the tongue,
elevate epiglottis and exposeelevate epiglottis and expose
the Vocal cordthe Vocal cord
 STRAIGHT BLADE- MILLERSTRAIGHT BLADE- MILLER
 CURVED BLADE- MACINTOSHCURVED BLADE- MACINTOSH

45. Equipment for Airway ManagementEquipment for Airway Management
 Endotracheal tubeEndotracheal tube
– Increases resistanceIncreases resistance
to gas flowto gas flow
– Increases dead spaceIncreases dead space
– IT or Z 79 (indicatesIT or Z 79 (indicates
lack of tissue toxicity)lack of tissue toxicity)
– High volume-lowHigh volume-low
pressure cuff preferredpressure cuff preferred
(<25 torr) : prevents(<25 torr) : prevents
tracheal mucosatracheal mucosa
ischemiaischemia

46. Equipment for Airway ManagementEquipment for Airway Management
 Endotracheal tubeEndotracheal tube
– Very flexible thus aVery flexible thus a
STYLET maybe neededSTYLET maybe needed
– Can be inserted orally,Can be inserted orally,
nasally or thru thenasally or thru the
tracheostomy stomatracheostomy stoma
– With Murphys eye ( allowsWith Murphys eye ( allows
ventilation even if main portventilation even if main port
is occludedis occluded
 StyletStylet
– Malleable metal insertedMalleable metal inserted
thru the tube for difficultthru the tube for difficult
intubationintubation

47. Equipment for Airway ManagementEquipment for Airway Management
 LMA (Laryngeal MaskLMA (Laryngeal Mask
Airway)Airway)
– Relatively new deviceRelatively new device
– Alternative to ETTAlternative to ETT
– Aspiration?Aspiration?
– Easier to insertEasier to insert
 ILMA (Intubating LMA)ILMA (Intubating LMA)
– An ETT may be inserted thruAn ETT may be inserted thru
the LMAthe LMA

48. Equipment for Airway ManagementEquipment for Airway Management
COMBITUBE

49. Equipment for Airway ManagementEquipment for Airway Management
GLIDESCOPEGLIDESCOPE

50. Equipment for Airway ManagementEquipment for Airway Management
 Fiberoptic BronchoscopeFiberoptic Bronchoscope

51. Equipment for Airway ManagementEquipment for Airway Management
 Cricothyrotomy KitCricothyrotomy Kit

52. Equipment for Airway ManagementEquipment for Airway Management
 Retrograde Intubation KitRetrograde Intubation Kit

53. Equipment for Airway ManagementEquipment for Airway Management
 Tracheostomy SetTracheostomy Set

54. Difficult AirwayDifficult Airway
 the clinical situation in which athe clinical situation in which a
conventionally trained anesthesiologistconventionally trained anesthesiologist
experiences difficulty with maskexperiences difficulty with mask
ventilation, difficulty with trachealventilation, difficulty with tracheal
intubation, or both.intubation, or both.

55. Prediction of the Difficult AirwayPrediction of the Difficult Airway
 Recent data from the Closed ClaimsRecent data from the Closed Claims
Project of the American Society ofProject of the American Society of
Anesthesiologists (ASA)Anesthesiologists (ASA)
Adverse respiratory eventsAdverse respiratory events – largest– largest
source of injurysource of injury
inadequate ventilationinadequate ventilation (38%)(38%)
esophageal intubationesophageal intubation (18%)(18%)
difficult intubationdifficult intubation (17%)(17%)

56. Prediction of the Difficult AirwayPrediction of the Difficult Airway
 Of these respiratory eventsOf these respiratory events
death or brain damage -death or brain damage - 85%85%
substandard care -substandard care - 12.5%12.5%
preventable -preventable - 12.5%12.5%
 Better prediction and anticipation of theBetter prediction and anticipation of the
difficult airway - lead to reduction in thesedifficult airway - lead to reduction in these
numbersnumbers

57. Definition of Terms – Four conceptsDefinition of Terms – Four concepts
 Difficult Mask VentilationDifficult Mask Ventilation
 Difficult LaryngoscopyDifficult Laryngoscopy
 Difficult IntubationDifficult Intubation
 Failed IntubationFailed Intubation

58. Difficult Mask VentilationDifficult Mask Ventilation
 No universally acceptable classificationNo universally acceptable classification
 (1) inability of unassisted anesthesiologist to(1) inability of unassisted anesthesiologist to
maintainmaintain SpO2 > 90%SpO2 > 90% using 100% oxygen andusing 100% oxygen and
positive pressure mask ventilation in a patientpositive pressure mask ventilation in a patient
whose SpO2 was 90% before anestheticwhose SpO2 was 90% before anesthetic
intervention; orintervention; or
 (2) inability of the unassisted anesthesiologist to(2) inability of the unassisted anesthesiologist to
prevent or reverse signs of inadequateprevent or reverse signs of inadequate
ventilation during positive pressure maskventilation during positive pressure mask
ventilation.ventilation.

59. Difficult LaryngoscopyDifficult Laryngoscopy
 difficult laryngoscopydifficult laryngoscopy = not being able to see any part of= not being able to see any part of
thethe vocal cordsvocal cords with conventional laryngoscopywith conventional laryngoscopy
 Cormack and Lehane ClassificationCormack and Lehane Classification
 Four grades of laryngoscopy based on structuresFour grades of laryngoscopy based on structures
visualizedvisualized
 Grade three and fourGrade three and four or grade four alone as correlatingor grade four alone as correlating
with a potentially difficult intubationwith a potentially difficult intubation

60. Difficult IntubationDifficult Intubation
 Less straightforwardLess straightforward
 In 1993, The ASA Committee on PracticeIn 1993, The ASA Committee on Practice
Guidelines for Management of the DifficultGuidelines for Management of the Difficult
Airway defined it as intubation when “theAirway defined it as intubation when “the
proper insertion of the ET tube withproper insertion of the ET tube with
conventional laryngoscopy requiresconventional laryngoscopy requires moremore
than three attempts and/or …more than 10than three attempts and/or …more than 10
minutesminutes

61. Failed IntubationFailed Intubation
 The inability to place the endotrachealThe inability to place the endotracheal
tube into the airwaytube into the airway
 0.05% or0.05% or 1:22301:2230 of surgical patientsof surgical patients
 0.13% to 0.35%, or 1:750 to0.13% to 0.35%, or 1:750 to 1:2801:280 ofof
obstetric patientsobstetric patients

62. DIFFICULT AIRWAY
GENERAL ANESTHESIA
+/- PARALYSIS
RECOGNIZED
PROPER
PREPARATION
ASA DIFFICULT AIRWAY ALGORITHMASA DIFFICULT AIRWAY ALGORITHM
UNRECOGNIZED
AWAKE
INTUBATION
CHOICES
SUCCEED
FAIL
SURGICAL
AIRWAY
MASK
VENTILATION
NO
YES
EMERGENCY
PATHWAY
NON -EMERGENCY
PATHWAY
LMA
COMBITUBE
TTJV
INTUBATION
CHOICES
INTUBATION
CHOICES
SURGICAL
AIRWAY
SUCCEED
FAIL
CONFIRM
ANESTHESIA
WITH MASK
VENTILATION
AWAKEN
SURGICAL
AIRWAY
EXTUBATE
OVER JET
STYLET
REGIONAL
ANESTHESIA
CANCEL
CASE
REGROUP
Intubation choices include use of different
laryngoscope blades, LMA as an intubation
conduit (with or without fiberoptic guidance),
fiberoptic intubation, intubating stylet or tube
changer, light wand, retrograde intubation,
and blind oral or nasal intubation.
*
*
*
AWAKEN

63. LMA in the Difficult Airway AlgorithmLMA in the Difficult Airway Algorithm

64. Techniques for Difficult VentilationTechniques for Difficult Ventilation
 two-person mask ventilationtwo-person mask ventilation
 oral and nasopharyngeal airwaysoral and nasopharyngeal airways
 laryngeal mask airwaylaryngeal mask airway
 esophageal-tracheal combitubeesophageal-tracheal combitube
 transtracheal jet ventilationtranstracheal jet ventilation
 rigid ventilating bronchoscoperigid ventilating bronchoscope
 surgical airway accesssurgical airway access

65. Techniques for Difficult IntubationTechniques for Difficult Intubation
 alternative laryngoscopic bladesalternative laryngoscopic blades
 intubating styletintubating stylet
 gum elastic bougiesgum elastic bougies
 awake intubationawake intubation
 fiberoptic intubationfiberoptic intubation
 blind intubation (oral or nasal)blind intubation (oral or nasal)
 retrograde intubationretrograde intubation
 surgical airway accesssurgical airway access

66. ASA Difficult Airway AlgorithmASA Difficult Airway Algorithm
Take-Home MessagesTake-Home Messages
 If suspicious of trouble –If suspicious of trouble – secure the airway awakesecure the airway awake
 If you get into trouble –If you get into trouble – awaken the patientawaken the patient
 Have a plan B and C immediately available or inHave a plan B and C immediately available or in
place –place – think aheadthink ahead
 Intubation choices –Intubation choices – do what you do bestdo what you do best

67. THANKS GUYS!THANKS GUYS!