Pediatric Airway Management

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Transcript Pediatric Airway Management

H. HOSSEINI MD
Airway anatomy differences
Airway anatomy differences
Airway Shape
Adapted from
Walls et al.
Manual of
Emergency
Airway Management.
2nd Ed. 2004.
2- Relatively Larger Tongue:
Obstructs airway
Obligate nasal breathers
Difficult to manipulate & stabilize with
laryngoscopic blades
4- Differently Shaped Epiglottis
Infant epiglottis ohmega (Ώ) shaped and angled away
from axis of trachea
More difficult to lift an infant’s epiglottis with
laryngoscopic blade
5- Funnel shaped larynx
The only complete ring
Narrowest part of infant’s larynx is the cricoid cartilage:
Tight fitting ETT may cause edema.
Uncuffed ETT preferred for patients < 8 years old
Recently, the concept of the child having a funnelshaped airway with the cricoid as the narrowest portion
of the airway has been challenged. Based on
bronchoscopic images,
Dalal and colleagues (2009) suggest for infants and
children the glottis, not the cricoid, may be the
narrowest portion.
Five Cardinal Anatomical Features
of Infant’s Larynx
1- Higher Larynx
Acute angulation between plane of tongue & plane of
glottis makes exposure difficult ►straight blade
►exaggerated by mandibular hypoplasia (Pierre Robin
syndrome).
Positioning
Adapted from
Walls et al.
Manual of
Emergency
Airway Management.
2nd Ed. 2004.
3- Anteriorly Angulated Vocal Cords:
The anterior attachment of vocal cords are lower than
posterior attachment ► difficulty in nasal intubations
where “blindly” placed ETT lodges in the anterior
commissure rather than in the trachea.
Respiratory Physiology
Obligate nasal breathers
 Immaturity of coordination between respiratory efforts
and oropharyngeal motor/sensory input.
 During quiet respiration, the tongue rests against the roof
of the mouth.
Respiratory Physiology
Respiratory Parameters
 High metabolic rate (5-8 ml/kg/min)
 Tidal volume (6-7 ml/kg/min)
 High respiratory rate (40-60 breaths/min)
 High alveolar ventilation (130 ml/kg/min)
 Lung compliance is less while chest wall compliance is
more than those in adults {reduced FRC and atelectasis}
►PEEP.
Respiratory Physiology
Effect of Edema on WOB
Laryngoscope Blades
Macintosh
Miller
Using The Miller Blade
Better in younger
children with a floppy
epiglottis
Straight Laryngoscope
Blade – used to pick up
the epiglottis
Intubation Positioning
 Goal is to align three axes
 OA/PA/LA
 Medical positioning
 Head tilt chin lift
 Towels (older = head, younger = shoulders)
 Trauma positioning
 Manual in-line stabilization
PositioningMedical
vs.
Trauma
Positioning
Intubation Approach
 Remember, much different than adults
 Externally
 Larger head/occiput
 Head flexes forward and can obstruct
 Internally
 Larger tongue
 Friable tissues
 Different angles and shapes
Airway Differences
Nose
Tongue
Trachea
Cricoid
Airway
Special Techniques for Intubation
Rigid Laryngoscopy
The retromolar, paraglossal, or lateral approach to rigid laryngoscopy
utilizing a straight blade.
ET Tube sizes





Age
kg
Newborn
3 mos
1 yr
2 yrs
12
ETT
3.5
6.0
10
4.5
Length (lip)
3.5
9
3.5
10
4.0
11
12
 Children > 2 years:
 ETT size:
 ETT depth (lip):
Age/4 + 4
Age/2 + 12
Equipment choosing
 Other methods for choosing ET tubes
Uncuffed tubes (in mm):
age
4
Cuffed tubes:
+ 4
Uncuffed size - 0.5
Tube Placement
 ETT depth – use the black line
 (Age in years/2) + 12
 ETT internal diameter x 3
Tracheal Tube Sizes
Insufflation Pressure ?
Muscle Relaxants?
Age
Size (mm ID)
Insertion length
(Alveolar ridge)
Preterm 1000g
Preterm 1000-2500g
2.5
3.0
6-9 cm
Neonate-6 Month
3.0-3.5
10 cm
6 Month – 1 Yr
3.5-4.0
11 cm
1-2 Yrs
4.0-5.0
12 cm
Beyond 2 Yrs
age (yrs)/4 + 4
age (yrs)/2 + 12
Techniques to open the Airway
Nasopharyngeal Airway
Size
Hazards: long, bleeding 30%, intracranial placement
Techniques to Open the Airway
Head tilt- Chin lift - Jaw Thrust – Oropharyngeal Airway
Aligning of the Upper Airway Axes
( More than 6 Years Old)
Three-axes theory?
Tracheal Intubation
Laryngoscopic Blade Sizes
Age
Miller
Macintoch
Preterm
0
-
Neonate
0
-
Neonate-2 Yrs
1
-
2-6 Yrs
-
2
6-12 Yrs
2
2
>12 Yrs
3
3
Micro-cuff ETT
More anatomical fit
Sealing at low pressures
More distal position
Greater permeability for nitrous
oxide
For neonates ≤3 kg and infants ≤1
year, ID 3.0-mm
For children 1 to 2 years of age, ID
3.5-mm
For children ≥2 years, ID (mm) =
age/4 + 3.5
Post-intubation croup was 0.4%
(2/500 children)
Endotracheal tubes fabricated without the Murphy eye
are known as Magill tubes,
whereas those that have this opening are called Murphy
tubes.
However, there are potential disadvantages to the
presence of a Murphy eye on an endotracheal tube,
including a tendency for accumulation of secretions and
the possibility that a stylet, catheter, or bronchoscope
may get stuck, requiring the removal of the entire
assembly.
LMA: Reusable Classic, Disposable Unique, ProSeal
Silicone
Softer,
deeper mask
bowl, bite
block,
improves
stability
PVC
Silicone
LMA Sizing
LMA Size
Patient Size
1
Neonate / Infants < 5 kg
1½
Infants 5-10 kg
2
Infants / Children 10-20 kg
2½
Children 20-30 kg
3
Children/Small adults 30-50 kg
4
Adults 50-70 kg
5
Large adult >70 kg
LMA
 Used in any age
 Easy to place
 Few complications
 Contraindications:
 Gag reflex
 FBs
 Airway obstruction
 High ventilation pressure
 Does not secure airway
Following its blind passage through the oral cavity, the
proper seating of an LMA is generally heralded by a
slight rise of the device when the mask’s cushion
is inflated with air. Care should be taken to use the
minimal effective inflation pressure for the cuff, typically
up to 60 cmH2O. The routine use of a manometer is
advocated
The more cephalad and anterior position of the larynx of
a child as compared with an adult has prompted the use
of an alternate insertion technique in children. In this
case, the LMA is inserted with its cushion placed against
the hard palate. The device is then rotated through 180
degrees until the cushion is seated at the laryngeal inlet .
This method for the insertion of an LMA appears to be
especially useful in preschool and young school-age
children.
LMA sizes
Mask size
Patient’s weight
Maximum cuff
volume (ml)
(Least effective
volume)
Largest TT (mm
ID)
1
1-5 kg
4
3.5
1.5
5-10 kg
7
4.0
2
10-20 kg
10
4.5
2.5
20-30 kg
14
5.0
3
> 30 kg
20
6.0, non-cuffed
Causes of Difficult Airway
Congenital Anomalies
Tumors
Infection
Musculoskeletal Problems
 Loose or missing teeth.
 Size and configuration of palate.
 Size and configuration of mandible (side view).
 Location of larynx in relation to the mandible.
 Presence of inspiratory stridor :epiglottitis, croup,
extrathoracic foreign body.
 Both inspiratory and expiratory stridor: aspirated foreign
body, vascular ring, or large esophageal foreign body.
 Prolonged expiration: lower airway disease?
 Baseline oxygen saturation in room air.
 Bilateral microtia (ear deformity easily notable) is
associated with mandibular hypoplasia & difficulty in
visualizing the laryngeal inlet (42%) & with unilateral
microtia (2.5%).
 Are there congenital anomalies that may fit a recognizable
syndrome? The finding of one anomaly mandates a search
for others.
microtia
Musculoskeletal Problems
Ankylosis of jaw, cervical spine
Unstable or dislocated cervical vertebrae
Wired jaw
Cervical cord tumor
Halo traction apparatus
Facial trauma, fractures, laceration, burns
Evaluation of the Upper Airway
(Diagnostic Testing)
 X-ray, MRI and CT.
Radiologic airway examination in a child with a compromised
airway must be undertaken only when there is no immediate
threat to the child's safety and only in the presence of skilled
and appropriately equipped personnel able to manage the
airway.
 Endoscopic evaluation (flexible fiberoptic endoscopy)
 Arterial blood gas analysis (chronic airway obstruction
with respiratory acidosis)
Encephalocele
Bilateral Cleft Palate
Hallermann-Streiff S.
Achondroplasia
Pierre Robin S.
Down S.
Crouzon S.
Seckel S.
Treacher Collins S.
Goldenhar S.
Apert S.
Nager S.
Mucopolysaccaridosis
Type IH (Hurler)
Type 1 H/S (Hurler-Scheie)
Type II Hunter
Type III (Sanfilippo)
Tumors
Cystic hygroma
Hemangioma of tongue, pharynx
Teratoma
Infection
Retropharyngeal abscess
Epiglottitis
Laryngotracheobronchitis
(subglottic croup)
Ludwig’s angina
Adenotonsillitis, abscess, hypertrophy (
obstructive sleep apnea)
Scleroderma
Laryngeal web
I-LMA
 Only sizes 3, 4, 5
 Same rules and sizing
as LMA
 Need special armored
tube for intubation
 New similar devices
exist
 Leave LMA portion in
place in field
Combitube
 Two sizes
 Small (4 to 5.5 feet tall)
 Regular (over 5.5 feet tall)
 Not useful in most kids
 Easy to place
 Contraindications
 Gag reflex
 Esophageal disease
 Caustic ingestions
 FBs/Airway obstruction
Bougie
 Replaces stylet
 Able to use with poor
view
 Feel tracheal rings
 Feel carina
 Intubate over it
 Keep blade in place
 Two person technique
 Need to practice
Other Toys
 Lighted stylet
 Flexible fiberoptic
scopes
 Rigid fiberoptic scopes
 Bullard
 Shikani
 Video laryngoscopy
Bullard laryngoscope
Optimal External Laryngeal Manipulation (OELM)
OELM is particularly helpful for infants & children with immobile or
shortened necks.
Either by an assistant or the laryngoscopist.
Intubation Guides
Lighted Stylet
Light Wand
TTJV
Glidescope Video Laryngoscope
Ventilation Techniques
Multi-handed Mask Ventilation
Intubation through LMA (Blind)
Fibreoptic Intubation through LMA
Fibreoptic Assisted Intubation
Surgical Airways Cricothyrotomy
 Indications (only if >10 years old)
 Failed airway
 Failed ventilation
 Predictors of difficulty
 Previous neck surgery
 Obesity
 Hematoma or infection
Cricothyrotomy Techniques
Open
 Locate CTM
 Stabilize larynx/prep
 Incise skin
 Vertical
 Horizontal through CTM
 Insert spacer/dilator
Closed
 Locate CTM
 Stabilize larynx/prep
 Insert needle
 Direct inferiorly
 Insert guidewire
 Remove needle
 Insert cuffed tube
 Small skin incision
 Check breath sounds
 Insert dilators/UC tube
 Check breath sounds
Percutaneous Cricothyrotomy
Percutaneous needle cricothyrotomy provides only a
mean for oxygen insufflation and does not reliably
provide adequate ventilation.
If glottic or subglottic pathology is not suspected, LMA
placement to establish ventilation may be
appropriately attempted first.
Cricothyrotomy Complications
 Bleeding
 Laryngeal or tracheal injury
 Infection
 Pneumomediastinum
 Subglottic stenosis
Retrograde Intubation
Broselow Tape
 8 color codes (6-36 kg)
 Broselow-Luten Emergency
System
 Color-coded bags with equip
 Quicker, more efficient
Broselow Tape
 Equipment sizes
 Airway adjuncts
 Intubation equip
 Oxygen delivery
 Vascular access
 Defibrillation
 NGT, suction caths
 BP cuff
 Chest tubes
 Foley
 Medications
 Antiarrhythmics
 Arrest medications
 Anticonvulsants
 Overdose meds
 Increased ICP meds
 Induction agents
 Paralytics
 Vasopressors
 IV drips
Broselow Tape
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