2. The Pediatric Airway
• Introduction
• Normal Anatomy
• Physiology
• Airway evaluation
• Management of
normal vs.
abnormal airway
• Difficult airway
3. Introduction
• Almost all of pediatric codes are due to
respiratory origin
• 80% of pediatric cardiopulmonary arrest are
primarily due to respiratory distress
• Majority of cardiopulmonary arrest occur at <1
year old
4. Normal Pediatric Airway Anatomy
• Larynx composed of
hyoid bone and a series
of cartilages
• Single: thyroid, cricoids,
epiglottis
• Paired: arytenoids,
corniculates, and
cuneiform
5.
6. Pediatric Anatomy cont.
Laryngeal folds consist of:
• Paired aryepiglottic folds extend from epiglottis
posteriorly to superior surface of arytenoids
• Paired vestibular folds (false vocal cords) extend
from thyroid cartilage posteriorly to superior surface of
arytenoids
• Paired vocal folds (true vocal cords) extend from
posterior surface of thyroid plate to anterior part of
arytenoids
• Interarytenoid fold bridging the arytenoid cartilages
• Thyrohyoid fold extend from hyoid bone to thyroid
cartilage
7. Pediatric Anatomy cont.
Sensory Innervation:
Recurrent Laryngeal Nerve-supraglottic larynx
Internal Branch of Superior Laryngeal Nerve-
infraglottic larynx
Motor Innervation:
External branch of Superior Laryngeal Nerve-
cricothyroid muscle
Recurrent Laryngeal Nerve-all other laryngeal muscles
Blood Supply
Laryngeal branches of the superior and inferior thyroid
arteries
8. 5 Differences between Pediatric
and Adult Airway
• More rostral larynx
• Relatively larger tongue
• Angled vocal cords
• Differently shaped epiglottis
• Funneled shaped larynx-narrowest
part of pediatric airway is cricoid
cartilage
9. More rostral pediatric larynx
Laryngeal apparatus develops from brachial clefts and
descends caudally
Infant’s larynx is higher in neck (C2-3) compared to adult’s
(C4-5)
10. Relatively larger tongue
• Obstructs airway
• Obligate nasal
breathers
• Difficult to visualize
larynx
• Straight laryngoscope
blade completely
elevates the epiglottis,
preferred for pediatric
laryngoscopy
11. Angled vocal cords
• Infant’s vocal cords
have more angled
attachment to trachea,
whereas adult vocal
cords are more
perpendicular
• Difficulty in nasal
intubations where
“blindly” placed ETT
may easily lodge in
anterior commissure
rather than in trachea
Image from: http://www.utmb.edu/otoref/Grnds/Pedi-airway-2001-
15. Funneled shape larynx
ADULT INFANT
• narrowest part of
infant’s larynx is the
undeveloped cricoid
cartilage, whereas in the
adult it is the glottis
opening (vocal cord)
• Tight fitting ETT may
cause edema and
trouble upon extubation
16. Funneled shape larynx
ADULT INFANT • Uncuffed ETT
preferred for
patients < 8 years
old
• Fully developed
cricoid cartilage
occurs at 10-12
years of age
17. Pediatric Respiratory Physiology
• Pulmonary surfactant produced by Type II
pneumocytes
at 24 wks GA
• Sufficient pulmonary surfactant present
after 35 wks GA
• Premature infants prone to respiratory
distress syndrome
(RDS) because of insufficient surfactant
• Betamethasone can be given to pregnant
mothers at 24-35wks GA to accelerate fetal
surfactant production
18. Pediatric Respiratory Physiology
• Extrauterine life not possible until 24-25 weeks of
gestation
• Two types of pulmonary epithelial cells: Type I
and Type II pneumocytes
• Type I pneumocytes are flat and form tight
junctions that interconnect the interstitium
• Type II pneumocytes are more numerous,
resistant to oxygen toxicity, and are capable of
cell division to produce Type I pneumocytes
19. Pediatric Respiratory Physiology cont.
• Work of breathing for each kilogram of
body weight is similar in infants and adult
• Oxygen consumption of infant (6
ml/kg/min) is twice that of an adult (3
ml/kg/min)
• Greater oxygen consumption = increased
respiratory rate
•
• Tidal volume is relatively fixed due to
anatomic structure
20. Pediatric Respiratory Physiology cont.
• Minute alveolar ventilation is more
dependent on increased respiratory rate
than on tidal volume
• Lack Type I muscle fibers, fatigue more
easily
• FRC of an awake infant is similar to an
adult when normalized to body weight
• Ratio of alveolar minute ventilation to FRC
is doubled, under circumstances of
hypoxia, apnea or under anesthesia, the
infant’s FRC is diminished and
desaturation occurs more precipitously
21. Physiology: Effect Of Edema
Poiseuille’s law
R = 8nl/ πr4
If radius is halved, resistance increases 16 x
Image from: http://www.hadassah.org.il/NR/rdonlyres/59B531BD-EECC-4FOE-9E81-14B9B29D139B1945/AirwayManagement.ppt
22. Normal Inspiration and Expiration
turbulence
Image from: http://www.hadassah.org.il/NR/rdonlyres/59B531BD-EECC-4FOE-9E81-14B9B29D139B1945/AirwayManagement.ppt
25. Airway Evaluation
Medical History
• URI predisposes to coughing,
laryngospasm, bronchospasm, desat
during anesthesia
• Snoring or noisy breathing (adenoidal
hypertrophy, upper airway
obstruction, OSA)
• Chronic cough (subglottic stenosis,
previous tracheoesohageal fistula
repair)
• Productive cough (bronchitis,
pneumonia)
• Sudden onset of new cough (foreign
body aspiration)
26. Airway Evaluation
Medical History
• Inspiratory stridor (macroglossia,
laryngeal web, laryngomalacia,
extrathoracic foreign body)
• Hoarse voice (laryngitis, vocal cord
palsy, papillomatosis)
• Asthma and bronchodilator therapy
(bronchospasm)
• Repeated pneumonias (GERD, CF,
bronchiectasis, tracheoesophageal
fistula, immune suppression,
congenital heart disease)
• History of foreign body aspiration
27. Airway Evaluation
Medical History
• Previous anesthetic problems
(difficulty intubation/extubation or
difficulty with mask ventilation)
• Atopy, allergy (increased airway
reactivity)
• History of congenital syndrome
(Pierre Robin Sequence, Treacher
Collins, Klippel-Feil, Down’s
Syndrome, Choanal atresia)
• Environmental: smokers
28. Signs of Impending Respiratory Failure
• Increase work of breathing
• Tachypnea/tachycardia
• Nasal flaring
• Drooling
• Grunting
• Wheezing
• Stridor
29. Supraglottic Glottic Subglottic
Trachea
Sound Sonorous, gurgling Biphasic stridor High-pitched stridor
Coarse, Inspiratory stridor
expiratory stridor,
Structures Nose / Pharynx / Epiglottis Larynx Subglottic trachea
Vocal cords
Congenital Micrognathia ,Pierre Robin Laryngomalacia Subglottic stenosis
Macroglossia, Vocal cord paralysis Tracheomalacia
Down syndrome Laryngeal web Tracheal stenosis
Storage disease Laryngocele Vascular ring
Choanal atresia Hemangioma cyst
Lingual thyroid
Thyroglossal cyst
Acquired Adenopathy Papillomas Croup
Tonsillar hypertrophy Foreign body Bacterial tracheitis
Foreign body Subglottic stenosis
Pharyngeal abscess Foreign body
Epiglottitis
Causes of Stridor: Anatomic Location, Sound, and Etiology
30. Signs of Impending Respiratory Failure
• Head bobbing
• Use of accessory muscles/retraction of muscles
• Cyanosis despite O2
• Irregular breathing/apnea
• Altered consciousness/agitation
• Inability to lie down
• Diaphoresis
31. Causes of acute upper airway obstruction that
are commonly life-threatening
Epiglottitis
Retropharyngeal abscess
Bacterial tracheitis
Croup
Foreign body
Anaphylaxsis
Neck trauma
Burns thermal or caustic
32. Airway Evaluation
Physical Exam
• Facial expression
• Nasal flaring
• Mouth breathing
• Drooling
• Color of mucous
membranes
• Retraction of
suprasternal, intercostal
or subcostal
• Respiratory rate
• Voice change
• Mouth opening
• Size of mouth
33. Airway Evaluation
Physical Exam
• Mallampati
• Loose/missing teeth
• Size and configuration of
palate
• Size and configuration of
mandible
• Location of larynx
• Presence of stridor
(inspiratory/expiratory)
• Baseline O2 saturation
• Global appearance
(congenital anomalies)
• Body habitus
34. Diagnostic Testing
• Laboratory and radiographic evaluation
extremely helpful with pathologic airway
• AP and lateral films and fluoroscopy may
show site and cause of upper airway
obstruction
• MRI/CT more reliable for evaluating neck
masses, congenital anomalies of the lower
airway and vascular system
35. Imaging may be
useful in identifying
the location and nature
of the airway
obstruction but should
never interfere
with the stabilization of a
child with
a critical obstruction.
39. MRI/CT
Usually not useful in an acute setting
More reliable for evaluating neck masses and
congenital anomalies of the lower airway
and vascular system
40. Diagnostic Testing
• Perform radiograph exam only when there is no
immediate threat to the child’s safety and in the
presence of skilled personnel with appropriate
equipment to manage the airway
• Intubation must not be postponed to obtain
radiographic diagnosis when the patient is
severely compromised.
• Blood gases are helpful in assessing the degree of
physiologic compromise; however, performing an
arterial puncture on a stressed child may
aggravate the underlying airway obstruction
42. Airway Management: Normal Airway
• Challenging because of unique anatomy
and physiology
• Goals: protect the airway, adequately
ventilate, and adequately oxygenate
• Failure to perform any ONE of these tasks
will result in respiratory failure
• Positioning is key!
43. Bag-Mask Ventilation
•Clear, plastic mask with inflatable rim •Place fingers on mandible to avoid
provides atraumatic seal compressing pharyngeal space
•Hand on ventilating bag at all times to
•Proper area for mask application-bridge
monitor effectiveness of spontaneous breaths
of nose extend to chin
•Continous postitive pressure when needed
•Maintain airway pressures <20 cm H2O to maintain airway patency
Image from: http://www.hadassah.org.il/NR/rdonlyres/59B531BD-EECC-4FOE-9E81-14B9B29D139B1945/AirwayManagement.ppt
44. Oropharyngeal Airway
PROPER
SIZE POSITION
Image from: http://www.hadassah.org.il/NR/rdonlyres/59B531BD-EECC-4FOE-9E81-14B9B29D139B1945/AirwayManagement.ppt
46. Nasopharyngeal Airway
•Distance from nares to angle of mandible approximates the
proper length
•Nasopharyngeal airway available in 12F to 36F sizes
•Shortened endotracheal tube may be used in infants or small
children
•Avoid placement in cases of hypertrophied adenoids -
bleeding and trauma
Image from: http://www.hadassah.org.il/NR/rdonlyres/59B531BD-EECC-4FOE-9E81-14B9B29D139B1945/AirwayManagement.ppt
47. Nasopharyngeal Airway
•Distance from nares to angle of mandible approximates the
proper length
•Nasopharyngeal airway available in 12F to 36F sizes
•Shortened endotracheal tube may be used in infants or small
children
•Avoid placement in cases of hypertrophied adenoids -
bleeding and trauma
Image from: http://www.hadassah.org.il/NR/rdonlyres/59B531BD-EECC-4FOE-9E81-14B9B29D139B1945/AirwayManagement.ppt
48. Sniffing Position
Patient flat on operating table, the oral (o),
pharyngeal (P), and tracheal (T) axis pass
through
three divergent planes
A blanket placed under the occiput aligns the
pharyngeal (P) and tracheal (T) axes
Extension of the atlanto-occipital joint aligns the
oral (O), pharyngeal (P), and tracheal (T) axes
Image from:
http://depts.Washington.edu/pccm/Pediatric%20Airway%20management.ppt
49. Selection of laryngoscope blade:
Miller vs. Macintosh
• Miller blade is preferred for infants and younger
children
• Facilitates lifting of the epiglottis and exposing
the glottic opening
• Care must be taken to avoid using the blade as a
fulcrum with pressure on the teeth and gums
• Macintosh blades are generally used in older
children
• Blade size dependent on body mass of the patient
and the preference of the anesthesiologist
50. Endotracheal Tube
Age Wt ETT(mm ID) Length(cm)
Preterm 1 kg 2.5 6
1-2.5 kg 3.0 7-9
Neonate-6mo 3.0-3.5 10
6 mo-1 3.5-4.0 11
1-2 yrs 4.0-5.0 12
51. Endotracheal Tube
New AHA Formulas:
Uncuffed ETT:
(age in years/4) + 4
Cuffed ETT: (age in years/4) +3
ETT depth (lip): ETT size x 3
52. Complications of Endotracheal Intubation
• Postintubation Croup
• Incidence 0.1-1%
• Risk factors: large ETT, change in patient
position introp, patient position other than
supine, multiple attempts at intubation,
traumatic intubation, pts ages 1-4, surgery
>1hr, coughing on ETT, URI, h/o croup
• Tx: humidified mist, nebulized racemic
epinephrine, steroid
53. Complications of Endotracheal Intubation
• Laryngotracheal (Subglottic) Stenosis
• Occurs in 90% of prolonged endotracheal
intubation
• Lower incidence in preterm infants and
neonates due to relative immaturity of cricoid
cartilage
• Pathogenesis: ischemic injury secondary to
lateral wall pressure from ETT edema,
necrosis, and ulceration of mucosa, infx
• Granulation tissues form within 48hrs leads
to scarring and stenosis
54. Cuff vs Uncuffed Endotracheal Tube
• Controversial issue
• Traditionally, uncuffed ETT recommended in
children < 8 yrs old to avoid post-extubation
stridor and subglottic stenosis
• Arguments against cuffed ETT: smaller size
increases airway resistance, increase work of
breathing, poorly designed for pediatric pts, need
to keep cuff pressure < 25 cm H2O
• Arguments against uncuffed ETT: more tube
changes for long-term intubation, leak of
anesthetic agent into environment, require more
fresh gas flow > 2L/min, higher risk for
aspiration
55. Cuff vs Uncuffed Endotracheal Tube
-Concluding Recommendations-
• For “short” cases when ETT size >4.0, choice of
cuff vs uncuffed probably does not matter
• Cuffed ETT preferable in cases of: high risk of
aspiration (ie. Bowel obstruction), low lung
compliance (ie. ARDS, pneumoperitoneum, CO2
insufflation of the thorax, CABG), precise control
of ventilation and pCO2 (ie. increased intracranial
pressure, single ventricle physiology)
56. Laryngeal Mask Airway
• Supraglottic airway device developed by Dr.
Archie Brain
• Flexible bronchoscopy, radiotherapy, radiologic
procedures, urologic, orthopedic, ENT and
ophthalmologic cases are most common pediatric
indications for LMA
• Useful in difficult airway situations, and as a
conduit of drug administration (ie. Surfactant)
• Different types of LMAs: Classic LMA, Flexible
LMA, ProSeal LMA, Intubating LMA
• Disadvantages: Laryngospasm, aspiration
58. Other Supraglottic Devices
• Laryngeal tube
• Latex-free, single-lumen silicone tube, which is closed at distal end
• Two high volume-low pressure cuffs, a large proximal oropharyngeal
cuff and a smaller distal esophageal cuff
• Both cuffs inflated simultaneously via a single port
• Situated along length of oropharynx with distal tip in esophagus
• Sizes 0-5, neonates to large adults (only sizes 3-5 available in US)
• Limited data available for its use in children
59. Other Supraglottic Devices
• Cobra Perilaryngeal Airway
• Perilaryngeal airway device with distal end shaped like a cobra-head
• Positioned into aryepiglottic folds and directly seats on entrance to
glottis
• Inflation of the cuff occludes the nasopharynx pushing the tongue and
soft tissues forward and preventing air leak
• Available in sizes pediatric to adult ½ to 6
• No studies currently available evaluating this device in children
61. Tracheotomy
Cricothyroidotomy is difficult
b/c of small membrane and
flexibility
Early complications
Pneumothorax, bleeding,
decannulation, obstruction,
infections
Late complications
Granuloma, decannulation,
SGS, tracheocutaneous
fistula
67. Congenital Anomalies
Tracheoesphageal Fistula
• Feeding difficulties (coughing,
choking and cyanosis) and breathing
problems
• Associated with congenital heart
(VSA, PDA, TOF), VATER, GI,
musculoskeletal and urinary tract
defects
• Occurs in 1/ 3000-5000 births
• Most common type is the blind
esophageal pouch with a fistula
between the trachea and the distal
esophagus (87%)
68. Congenital Anomalies
Tracheoesphageal Fistula
Radiograph of a
neonate with
suspected esophageal
atresia. Note the
nasogastric tube
coiled in the proximal
esophageal pouch
(solid arrow). The
prominent gastric
bubble indicates a
concurrent
tracheoesphageal
fistula (open arrow)
69. Congenital Anomalies
Choanal Atresia
• Complete nasal obstruction
of the newborn
• Occurs in 0.82/10 000
births
• During inspiration, tongue
pulled to palate, obstructs
oral airway
• Unilateral nare (right>left)
• Bilateral choanal atresia is
airway emergency
• Death by asphyxia
• Associated with other
congenital defects
71. Clinical manifestations
• - unilateral :
Asymptomatic for along period till the first attack of upper
respiratory tract infection,diagnosis may be suggested by
nasal discharge or persistent nasal obstruction .
• - bilateral :
Difficulty with mouth breathing make vigerous attempts to
inspire , often suck in their lips ,and develop cyanosis .
Distressed children then cry ( which relieve the cyanosis ) and
become more calm with normal skin colour , only to repeat
the cycle after closing their mouths . Those who are able to
breath through their mouths at once experience difficulty
when suckling and swallowing , becoming cyanotic when
they attempt to feed .
72. diagnosis
• - inablity to pass afirm cather 3 to 4 cm
into the nasopharynx through each nostril .
• - the atritic plate can be seen directly with
fibro optic rhinoscopy .
• -the anatomy is best evaluated by using
high resolution CT scan .
73. treatment
• - bilateral : -
• - An oral airway or intubation .
• - trasnasal endoscopic surgical repair .
• - stents are usually left in place after the repair for
weeks to prevent restenosis or closure .
• - tracheostomy should be considered in child has
other potentially life threatening problems and in
whom early surgical repair of the choanal atresia
may not be appropriate or feasible .
74. treatment
• - unilateral :-
• - operative correction may be deffered for
several years
• - in both nuilateral or bilateral cases ,
restenosis necessitating dilatation or
reoperation , or both , is common .
• - mitomycin-c has been used to help
prevent the development of granulation
tissue and stenosis .
75. Congenital Syndromes
Pierre Robin Sequence
• Occurs in 1/8500 births
• Autosomal recessive
• Mandibular hypoplasia, micrognathia,
cleft palate, retraction of inferior dental
arch, glossptosis
• Severe respiratory and feeding
difficulties
• Associated with OSA, otitis media,
hearing loss, speech defect, ocular
anomalies, cardiac defects,
musculoskeletal (syndactyly, club feet),
CNS delay, GU defects)
77. Congenital Syndrome
Treacher Collins Syndrome
• Mandibulofacial dysotosis
• Occurs in 1/10 000 births
• Cheek bone and jaw bone underdeveloped
• External ear anamolies, drooping lower
eyelid, unilateral absent thumb
• Respiratory difficulties
• Underdeveloped jaw causes tongue to be
positioned further back in throat (smaller
airway)
• Associated with OSA, hearing loss, dry
eyes
79. Congenital Syndrome
Down’s Syndrome
• Trisomy 21
• Occurs in 1/660 births
• Short neck, microcephaly, small mouth
with large protruding tongue, irregular
dentition, flattened nose, and mental
retardation
• Associated with growth retardation,
congenital heart disease, subglottic
stenosis, tracheoesophageal fistula,
duodenal atresia, chronic pulmonary
infection, seizures, and acute lymphocytic
leukemia
• Atlantooccipital dislocation can occur
during intubation due to congenital laxity
of ligaments
81. Inflammatory (Epiglottitis)
• Etiology: Haemophilus influenzae type B
• Occurs in children ages 2-6 years
• Disease of adults due to widespread H. influenza
vaccine
• Progresses rapidly from a sore throat to dysphagia
and complete airway obstruction (within hours)
• Signs of obstruction: stridor, drooling, hoarseness,
tachypnea, chest retraction, preference for upright
position
• OR intubation/ENT present for emergency surgical
airway
• Do NOT perform laryngoscopy before induction of
anesthesia to avoid laryngospasm
• Inhalational induction in sitting position to maintain
spontaneous respiratory drive (Sevo/Halothane)
• Range of ETT one-half to one size smaller
84. The treatment of epiglottitis.
Instrumentation: Avoid instrumentation. In suspected
epiglottitis.
Specialist consult: An anesthesiologist or otorhinolaryngologist
should be involved early in the management of epiglottitis.
Monitoring: Patients must be monitored for respiratory fatigue
visually and with continuous pulse oximetry. Accessibility to
equipment and expertise for immediate intubation is required
in the event of respiratory failure. If endotracheal intubation is
not possible, cricothyroidotomy may be required.
Oxygen: Oxygen is administered according to pulse oximetry
results. Dry air may worsen inflammation. Use of humidified
oxygen or a room humidifier is recommended.
Antibiotics: Presumptive intravenous antibiotics are indicated,
tailored to results from blood cultures.
85. The treatment of epiglottitis.
Glucocorticoids: Either intravenous or inhaled glucocorticoids
are sometimes given to reduce inflammation. However,
controlled trials of the effectiveness of this approach in
epiglottitis are limited.
Volume deficits: Correct volume deficits with intravenous fluids.
Sedatives: Avoid sedatives that may suppress the respiratory
drive.
Other medications: In patients with croup, aerosolized racemic
epinephrine is sometimes used to reduce mucosal edema;
however, the role of this drug in persons with epiglottitis is
not defined. Adverse events have been reported in patients
with epiglottitis.24 Beta-2 agonists are not typically used in
patients who do not have asthma
86. The treatment of epiglottitis.
Glucocorticoids: Either intravenous or inhaled glucocorticoids
are sometimes given to reduce inflammation. However,
controlled trials of the effectiveness of this approach in
epiglottitis are limited.
Volume deficits: Correct volume deficits with intravenous fluids.
Sedatives: Avoid sedatives that may suppress the respiratory
drive.
Other medications: In patients with croup, aerosolized racemic
epinephrine is sometimes used to reduce mucosal edema;
however, the role of this drug in persons with epiglottitis is
not defined. Adverse events have been reported in patients
with epiglottitis.24 Beta-2 agonists are not typically used in
patients who do not have asthma
87. Inflammatory
• Etiology: Parainfluenza virus
• Occurs in children ages 3 months to 3 years
• Barking cough
• Progresses slowly, rarely requires
intubation
• Medically managed with oxygen and mist
therapy, racemic epinephrine neb and IV
dexamethasone (0.25-0.5mg/kg)
• Indications for intubation: progressive
intercostal retraction, obvious respiratory
fatigue, and central cyanosis
