This document discusses pre-operative evaluation and airway management. The objectives of pre-operative evaluation are to establish medical and medication histories, perform a physical exam, obtain consent, and develop an anesthesia plan. Goals include informing patients of risks, educating them on anesthesia procedures, and answering questions. Pre-operative evaluation involves reviewing a patient's medical history, performing a physical exam including vital signs and airway assessment, assigning an ASA classification, and considering appropriate pre-operative tests and fasting guidelines. The document also discusses airway anatomy, evaluation techniques like Mallampati scoring, and airway management options including face masks, oropharyngeal and nasopharyngeal airways, laryngoscopy, and endotrache

1. PRE-OPERATIVE EVALUATION AND
AIRWAY MANAGEMENT
CC Jackie Lou C. Acha
Department of Anesthesiology
West Visayas State University Medical Center
August 27, 2013

2. Objectives of Preoperative Evaluation
• To establish a medical, anesthesia and
medication history
• To perform a physical exam
• To establish a doctor-patient relationship
• To obtain consent
• To make an anesthesia plan

3. Goals of Pre-operative Evaluation
• Inform the patient of the risks
• Educate the patient regarding anesthesia and
perioperative events
• Answer question and reassure the patient and
family
• Notify NPO status
• Instruct allowable and prohibited medications

4. Pre-Anesthetic Evaluation
Purpose: Review of Database
1. MEDICAL HISTORY
a. Current Problem
b. allergies
c. drug intolerances
d. present therapy
e. illicit drug use
f. previous anesthetic experience

5. 2. PHYSICAL EXAMINATION
 Vital Signs
 Airway
 Heart
 Lungs
 Extremities
 Neurologic Examination

6. 3. ASA Classification
Class Definition
1 A normal healthy patient
2 A patient with mild systemic disease and no functional
limitations
3 A patient with moderate-severe disease that limits activity
4 A patient with severe systemic activity that is a constant
threat to life
5 A moribund patient who is equally likely to die in the next
24 hours with or without surgery
6 A brain-dead patient for organ donation
“E” Added for Emergency operations

7. • AIRWAY EXAMINATION
Mallampati Classification
Class Direct Visualization
I Soft palate, fauces, uvula, pillars
II Soft palate, fauces, uvula
III Soft palate, uvular base
IV Hard palate Only

8. Routine Pre-Operative Laboratory Evaluation
Hemoglobin or Hematocrit
-All menstruating women
-All patients over 60 years of age
-All patients likely to experience significant
blood loss and may require transfusion
Serum Glucose and Creatinine
-All patients over 60 years of age
-Diabetic patients

9. Electrocardiogram (ECG)
-patients > 40 yo
-specific indications – HPN, palpitations, previous MI
Chest Radiograph
-patients > 60 yo
-specific clinical indications – HPN, malignancy, acute
pulmonary symptoms

10. • Urinalysis
• T3, T4, TSH

11. Preoperative Fasting
• Recommended fasting period
– 2 hours for clear liquids in all patients
– > 6 hours after a light meal
– 8 hours after a meal that includes fried or fatty
foods

12. PRE-OPERATIVE MEDICATION
• Psychological Preparation
• Pharmacologic Preparation

13. Primary Goals of Pharmacologic
Premedication
1. Relief of anxiety
2. Sedation
3. Amnesia
4. Analgesia
5. Prevention of airway secretion
6. Prevention of autonomic reflex responses
7. Reduction of gastric fluid volume
8. Increase in gastric fluid pH
9. Reduction of anesthetic requirements
10. Prophylaxis against allergic reaction

14. Secondary Goals of Pharmacologic
Premedication
1. Decrease vagal activity
2. Facilitation of smooth induction of
anesthesia
3. Post-operative analgesia
4. Prevention of post-operative nausea and
vomiting

15. Drug Classes for Premedication
o Benzodiazepines
o Opioids
o Anthihistamines
o Anticholinergics
o Histamine receptor antagonists (H2 antagonists)
o Antacids
o Proton pump inhibitors
o Antiemetics
o Gastrokinetic agents
o A2-adrenergic agonists

16. Airway Management
• For successful airway management
 Anatomy of airway
 Evaluation of airway
 Proper equipments
 Adequate skills

17. Anatomy of the Airways

18. Nasal and Oral Cavity
• Warms and humidifies
the air
• Provides 2/3 of airway
resistance

19. Pharynx
• Anteriorly communicate
with nasal and oral cavity
and larynx
• 3 parts of pharynx:
– Nasopharynx
– Oropharynx – at the level
of C2-C3
– Hypopharynx - at the level
of C4-C6
• Epiglottis – demarcate
oropharynx and
hypopharynx
– Adults – crescent shape
– Infants – u-shape

20. Larynx
• Cartilaginous skeleton
• 9 cartilages (3 paired
and 3 unpaired)
– 3 paired
• Arytenoid
• Corniculate
• Cuneiform
– 3 unpaired
• Thryroid
• Cricoid
• Epiglottis

21. Larynx

22. Trachea
• ~15 cm in adults
• Supported by 17-18 C-
shaped cartilages
• 1st tracheal ring –
anterior of 6th cervical
vertebrae
• Ends at the carina at
the level of 5th thoracic
vertebra

23. Primary Bronchi
• Right principal bronchus
– 1.8 cm long
– larger than the left
– deviates less from the
axis of the trachea
• Left principal bronchus
– 5 cm long

24. Adult vs Pediatric Airway

25. Evaluation of the Airway
• PATIENT HISTORY
– Symptoms related to the airway should be elicited
• Snoring
• Chipped teeth
• Changes in voice
• Dysphagia
• Stridor
• Bleeding
• Cervical spine pain or limited ROM
• TM joint pain/dysfunction
– Previous problems with airway

26. Evaluation of the Airway
• PHYSICAL EXAMINATION
– Thyromental distance – measure mentum to
thyroid notch in the neck extended position
• <6-7 cm or 3 fingerbreadth – poor laryngoscopic view
– Interincisor gap
• interincisor distance with the mouth fully opened
• <3 cm – poor laryngoscopic view

27. Evaluation of the Airway
– Atlanto-Occipital Extension/Neck Mobility
• Flexion of the neck and elevating head ~3cm – aligns
laryngeal and pharyngealaxis to obtain line of vision
during laryngoscopy
– Submandibular compliance
• Area in which pharyngeal soft tissue must be displaced
to obtain the line of vision during laryngoscopy

28. Evaluation of the Airway
– Mallampati Classification
• Correlation of oropharyngeal space with ease of direct
laryngoscopy and intubation
• Observer at eye level, head in neutral position, maximal
mouth opening and tongue protrusion without
phonating
• Examination of oropharyngeal structure

30. Mallampati Airway Classification
• Class I: soft palate, fauces, uvula, pillars
• Class II: soft palate, fauces, portion of uvula
• Class III: soft palate and base of uvula
• Class IV: hard palate only
A high Mallampati score (class 3 or 4) is
associated with more difficult intubation

31. Evaluation of the Airway
• The efficacy of direct laryngoscopy is measured in
terms of the best view of the larynx achieved
• Cormack and Lehane Score
• Laryngoscopic view
• Visualization of the entire laryngeal aperture

32. Cormack and Lehane Score
• Grade 1: most of glottis visible
• Grade 2: only posterior portion of glottis
• Grade 3: only epiglottis
• Grade 4: no airway structures visible

33. Upper Airway Obstruction

34. Signs of Upper Airway Obstruction
• Hoarse voice
• Decreased air in and out
• Stridor
• Retraction of
suprasternal/supraclavicular/intercostal space
• Cyanosis

35. Upper Airway Obstruction
• Head extension and jaw thrust
– move the hyoid bone and attached structures
anteriorly and relieve airway obstruction to a
variable extent

36. Head Extension

37. Jaw Thrust
• Achieved by exerting
anterior pressure
behind the angles of the
mandible
• Uses the sliding
component of the TMJ
to move the mandible,
hyoid bone, and
attached structures
anteriorly

38. Oxygenation and Preoxygenation
• A.K.A. denitrogenation
• Maximize O2 stores before induction to
prolong the period before the onset of
hypoxemia in the event of serious difficulty
with airway management
• 100% O2 from a close-fitting facemask before
induction of anesthesia

39. Breathing 100% O2
– Three minutes of tidal volume breathing
– Deep breathing with a high fresh gas flow for 1.5
minutes
5 minutes of 100% O2, via tight fitting face mask
– furnish up to 10 minutes of O2 reserve after
apnea

40. Airway Management Techniques
Face Mask Ventilation
– simplest and least
invasive anesthesia
technique
– suitable for short
operations
– also used for controlled
ventilation before and
after the use of
tracheal tubes

41. Face Mask
• should fit over the bridge
of the nose with the
upper border aligned with
the pupils
• Sides should seal just
lateral to the nasolabial
folds
• Bottom should seat
between the lower lip
and chin
• Ventilating pressure
< 20cm H2O

42. Sealing the Mask to the Face
• 1st requirement to ensuring
good fit
– Air-filled cushion that does
not leak
• Hypothenar eminence
– Used to draw the soft tissue
of the left cheek to meet the
cushion
• Ulnar 3 fingers of the left
hand
– Grip the mandible to displace
anteriorly
• Thumb and index finger
– Holds the mask on the face

43. Assessment of Ventilation
Adequate Ventilation Inadequate ventilation
Normal breath sounds Stridor, phonation, snoring
Sequential rise and fall of the subcostal
region
Motionless subcostal region
Upper chest expansion before or during
subcostal expansion
Upper chest retraction during subcostal
expansion; intercostal or
supraclavicular retraction, tracheal tug,
flaring nasal alae
Prompt refilling of the reservoir bag
during exhalation
Depleted reservoir bag
Appropriate tidal volume measured
with each breath
Reduced tidal volume measure
Square shaped capnogram with
normal end-expiratory CO2
Capnogram without plateau; large or
small end expiratory CO2
SpO2>97% SpO2<97%
Normal VS and ECG Abnormal VS and ECG

44. • If head extension and jaw thrust fail to
maintain an unobstructed airway
– oropharyngeal airway
– nasopharyngeal airway
– SAD
– tracheal intubation

45. Oropharyngeal Airway
• Keep the tongue from
blocking the airway
• Allow for easier
suctioning of the airway
• Used on unconscious
patients without a gag
reflex
• Used in conjunction
with bag valve mask

46. Nasopharyngeal Airways
• Conscious patient who
cannot maintain airway
• Can be used with intact
gag reflex
• Should not be used with
head injuries or
nosebleeds

47. Endotracheal Intubation
• Indications
- Provide a patent airway
- Prevent aspiration of gastric contents
- Need for frequent suctioning
- Facilitate positive-pressure ventilation of the lungs
- Operative position other than supine
- Operative site near or involving the upper airway
- Airway maintenance by mask difficult

48. Equipments for ET Insertion
• Endotracheal tube
• Suction catheter
• Laryngoscope
• Laryngoscope blades
• Equipment for providing positive-pressure
ventilation of the lungs with oxygen

49. Technique
• Elevate head 8-10 cm
• Extend head at atlanto-occipital joint
=> “Sniff position”
• Patient’s face near intubator’s xiphoid
cartilage
• Counter pressure of the right thumb on
mandibular teeth and right index finger on the
maxillary teeth => Scissors maneuver

50. Sniff Position

51. Scissors Maneuver

52. Sellick Maneuver
• Exert downward external
pressure to displace the
cartilaginous cricothyroid
ring posteriorly
• Compress esophagus
against cervical vertebrae
• Prevent spillage of gastric
contents into pharynx
• 30 to 40 Newtons or 8-9
pounds weight force
• Pressure released once the
airway is secured & cuff
inflated

53. Endotracheal Intubation

54. Laryngoscopy – positioning of head &
insertion of blade
• Laryngoscope is held in
the left hand
• Blade inserted on the
right of the patient’s
mouth
• Pressure on the teeth
and mouth must be
avoided while
advancing the blade
forward

55. Laryngoscopy – lifting the handle
• Depression or lateral
movement of the
patient’s thyroid
cartilage externally on
the neck (OELM) or
backward upward
rightward pressure
(BURP) may facilitate
exposure of the glottic
opening

56. Laryngoscopy – continue to lift the blade
towards roof

57. Insertion of endotracheal tube
• Tube is held in the right
hand like a pencil
• Curve directed
anteriorly
• Advance toward the
glottis from the right
side of the mouth
• Tube is advance until
proximal end is 1-2cm
past the vocal cords

58. Laryngoscopic view

59. • Remove laryngoscope blade
• Inflate ET cuff to create a seal against the
tracheal mucosa

60. Laryngoscopic view

61. Post-intubation auscultation
1. Right infra-
clavicular
3. Right infra-
mammary
5. Gastric
2. Left infra-
clavicular
4. Left infra-
mammary

62. Laryngoscope

63. Curved Macintosh Laryngoscope

64. Curved Macintosh Laryngoscope
• Tip is advanced into the space between the
base of the tongue and pharyngeal surface of
the epiglottis
• Forward and upward movement stretches the
hypoepiglottic ligament, elevates the
epiglottis and exposes the glottic opening
• Blade 3 or 4 standard for adult

65. Straight (Miller) blade
• Tip is passed beneath the laryngeal surface of
the epiglottis
• Forward and upward movement directly
elevates the epiglottis to expose
the epiglottic opening

66. Curved vs. Straight Blade
• Curved blade
– less trauma to the teeth with more room for
passage of ET and less bruising of the epiglottis
• Straight blade
– better exposure of the glottic opening

68. Endotracheal Tube
• Specified according to internal diameter
• Made of clear, inert polyvnyl chloride plastic
that molds to the contour of the airway after
softening on exposure to body temperature

69. ET Sizes
Age Weight (Kg) ET (mm)
Premature <1.5 2.5
Premature 1.5 – 2.5 3.0
Newborn 3.5 3.5
1 10 4.0
2-3 15 4.5
4-6 20 5.0
7-9 30 5.5
10-12 40 6.0
13-15 50 6.5
>16 >60 7.0

70. • Rigid implement made of flexible metal
• Inserted inside endotracheal tube to maintain
chosen shape
• It is bent over the tube to prevent protrusion
beyond the endotracheal tube & cause injury
• Facilitates intubation when glottis
visualization is minimal / absent & a semi-
blind or blind insertion is attempted
Stylet

71. Stylet

72. Complication of ET intubation
• Direct trauma
• Dental injury
• Systemic hypertension and tachycardia

73. Extubation
• Either deeply anesthetized or fully awake
• If under light anesthesia ( disconjugate gaze,
breath-holding or coughing and not
responsive to command) – laryngospasm
• Preferred if at risk from increased intracranial
or intraocular pressure, surgical wound
bleeding, or wound dehiscence

74. Checklist for Extubation
 No medical indication for continued intubation
 Muscle relaxants fully reversed
 Spontaneous ventilation is adequate
 Desired level of consciousness achieved
 All equipment for airway management present
 Denitrogenate with high flow oxygen
 Clear pharynx for suction
 Deflate the cuff
 Apply positive pressure to the breathing system and gently remove the
tracheal tube
 Clear the pharynx by suction again
 Reassess airway patency and ventilation
 Apply mask with high flow oxygen
 Check vital signs

75. Extubation complications
• Laryngospasm
• Inhalation of gastric contents
• Pharyngitis (disappears after 48-72H)
• Damage to tracheal mucosa
• Tracheal stenosis

76. THANK YOU!