Pediatric Airway Management4- Differently Shaped Epiglottis
Infant epiglottis ohmega () shaped and angled away from axis of trachea
More difficult to lift an infant’s epiglottis with laryngoscopic blade
5- Funnel shaped larynx
Narrowest part of infant’s larynx is the cricoid cartilage:
Tight fitting ETT may cause edema.
Uncuffed ETT preferred for patients < 8 years old
The only complete ring
Recently, the concept of the child having a funnel-shaped 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
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
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
Straight Laryngoscope Blade – used to pick up the epiglottis
Intubation - Positioning
OA/PA/LA
Trauma positioning
Externally
Internally
ET Tube sizes
Newborn 3.5 3.5 9
Children > 2 years:
Equipment choosing
Uncuffed tubes (in mm):
(Age in years/2) + 12
Tracheal Tube Sizes Insufflation Pressure ? Muscle Relaxants?
Insertion length (Alveolar ridge)
Nasopharyngeal Airway
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?
Macintoch
Miller
Age
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
PVC
Silicone
LMA Sizing
LMA Size
Patient Size
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
Patient’s weight
Loose or missing teeth.
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
Wired jaw
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
Scleroderma
Same rules and sizing as LMA
Need special armored tube for intubation
New similar devices exist
Combitube
Regular (over 5.5 feet tall)
Not useful in most kids
Easy to place
Feel tracheal rings
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
Intubation through LMA (Blind)
Fibreoptic Intubation through LMA
Failed airway
Failed ventilation
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
Broselow-Luten Emergency System