New Orleans EMS Airway Lecture Series: Lecture 4 The Pediatric Airway

1. New Orleans EMS Airway Lecture Series: Lecture 4The Pediatric Airway Jeffrey M. Elder, M.D. Deputy Medical Director

2. Challenges of the Pediatric Airway • Age related dosing and equipment • Anatomical Variations based on age • Anxiety of a sick child

3. Pediatric AirwayAnatomy

4. Tongue • Located completely in the oral cavity until 2 years old • No portion makes up the upper/anterior pharyngeal wall • Potential site of airway obstruction • Difficult ventilation

5. Occiput • A child’s head/occiput are proportionately larger than and adult’s • Neck flexion while supine • Leads to obstruction • Overcome with the sniffing position (want EAC just anterior to the shoulders) • Roll placed under back(infant) • None – small child • Roll placed under occiput

6. Positioning

7. Sniffing Position

8. Nasal Passage • Increased mucosa and lymphoid tissue • Nasal airway is primary pathway for normal breathing in the infant • Warming, humidification, particle filtration • Compromised breathing with increased secretions, NGT placement, nasal congestion

9. Larynx • Newborns • Larynx at the base of the occiput/C1 to C4 • Enables epiglottis to lock the larynx into the nasopharynx by passing up behind the soft palate • Provides a direct air channel from the nares to the lungs, allowing liquids to pass on the sides into the esophagus

10. Larynx • Two separate anatomic pathways • Respiratory tract from the nose to the lungs • Digestive tract from the mouth to the stomach • Large Tongue • Entirely within the oral cavity • High Glottis • Difficult line of vision from mouth to the larynx during laryngoscopy • Anterior Airway

11. Anatomic Changes in Childhood • Occurs after the second year of life • Posterior 1/3 of tongue descends into the neck, forming upper anterior pharyngeal wall • By 7 years, the larynx lies between C3 and C6 • In adulthood, the larynx lies between C4 – C7 • Now loose the two separate pathways

12. Anatomy • In adults, the vocal cords and trachea are of equal dimensions • In newborns, the narrowest portion of the airway is the cricoid ring • Tight ET tubes may lead to cricoid damage, subglotticstenosis

13. Functional Issues • Children easily obstruct the airway • Racemic epinephrine can have dramatic results in the smallest areas of the airway (croup –cricoid ring) • Larger airway calibers do not see such dramatic results (epiglotitis) – forced nebs can lead to dynamic upper airway obstruction • Noxious stimuli can lead to dynamic obstruction and respiratory arrest • Crying child increases work of breathing 32-fold – “leave them alone” • BMV may bridge through an obstruction • i.e. Epiglotitis • Increased inspiratory effort may collapse the airway – (extrathoracic trachea) • PPV can stent the airway open are relieve the obstruction

14. Physiology • Basal Oxygen consumption is approximately twice that of adults • Children have a decreased functional residual capacity (FRC) to body weight ratio • Desaturate much more quickly!! • Even given equivalent duration of preoxygenation • Be prepared to provide supplemental oxygen by BMV if oxygen saturation drops below 90%

15. Airway Management

16. Evaluation • History • PMHx, Prematurity, Previous Intubations • Observation • Tachypnea • Accessory Muscle Use • Nasal Flaring • Tripoding

17. Evaluation • Position of comfort • Grunting • Cyanosis • Drooling • Wheezing • Rales

18. Signs of Respiratory Failure • Decreased level of consciousness • Grunting and increased work of breathing • Poor Air Entry / Decreased breath sounds • Bradycardia • Apnea/Slow Respiratory Rate

19. Reasons to Intubate • Failure to Oxygenate • Failure to Ventilate • Expected Clinical Course

20. Airway Management

21. The 7 P’s of RSI • Preparation • Preoxygenation • Pretreatment • Paralysis with induction • Positioning • Placement with proof • Postintubation management

22. Airway Equipment • Suction Device • Oxygen source • Bag Valve Mask • ET Tube • 1 size smaller and larger • Laryngoscope blade & Handle • EtCO2 Detector • Tube Holder • Alternate Airway Equipment • OPA, Combitube, LMA, cric. kit • RSI Medications

23. Equipment Sizes • ET Tube • Diameter = (age/4) + 4 • Width of child’s 5th fingernail • Depth = Tube Size x 3 • Uncuffed Tube for less than 8 years old • Laryngoscope Blade • Be careful of size 0 and 00 • Based on Broselow Tape

24. Bag Valve Mask Ventilation • Must fit over the nose, cheeks, mouth, and chin • Place in sniffing position • In line stabilization • Jaw thrust • OPA/NPA • From ear to mouth • Inspect for foreign body • Cricoid pressure

25. Bag Valve Mask Ventilation • Pediatric/Adult Size bag • Pop off valve 35-45 cm of water • A skill that needs practice! • 1 or 2 person ventilation

26. Rapid Sequence Induction • Etomidate 0.3 mg/kg • Succinylcholine 2 mg/kg • faster metabolism than adults • Still first line for full-stomach or emergency intubation • Rocuronium 1 mg/kg • Atropine 0.02 mg/kg min. 0.1mg • Lidocaine 1mg/kg

27. Endotracheal Intubation • Usually after airway control and ventilation/oxygenation • Preoxygenation • Don’t bag – 3 minutes of 100% oxygen via BVM • Pick the right equipment! • Most effective and reliable airway management/protection • Always a clinical decision

28. Endotracheal Intubation • Attempts should not last over 30 seconds • Straight or Curved blade • Miller – picks up epiglottis • Straight blades preferred in small children • Picks of epiglottis directly and tongue/mandible more easily elevated from field of vision • Macintosh – enter the vallecula

29. Post Intubation Management • Verification of Tube Placement • Visualization • ETC02 • Auscultation • Secure the tube with tape or commercial device • Head/neck immobilization in small children to avoid neck movement and dislodgement

30. Post Intubation Management • Place NG tube after ETI • Decompress the stomach • Avoid micro aspiration in mechanically ventilated patients

31. Contraindications to RSI • Major Laryngeal trauma • Upper Airway Obstructions • Distorted Facial/Airway Anatomy • Operator Concern of Difficult Airway

32. The Difficult Airway

33. The Difficult Airway • Direct Examination • Mental-Hyoid Distance • Upper-Lower Incisor Distance • Large Tongue • Blood, swelling, secretions • Limited C spine mobility/scoliosis • Limited mandibular ROM • Maxillofacial/ Larynx trauma • *Angoiedema • *Anaphylaxis • *Epiglottitis • *Croup • Morbid Obesity • Micrognathia • Burns • Foreign Body

34. Adjunct AirwaysCombitube • Only if > 4 feet tall • Rescue Airway Device

35. Adjunct AirwaysLMA • Rescue option in the failed airway • May cause partial airway obstruction in infants (rotational placement) • Loss of seal/movement • Contraindicated in FB aspiration obstruction

36. Adjunct AirwaysLMA

37. Adjunct AirwaysCricothyroidotomy • Contraindicated < 10 yrs • Needle Cric <10 yrs • 14g needle, 5cc syringe, 3mm ETT adapter, BVM • Can’t intubate, Can’t ventilate • Trauma, angioedema, epigolttitis

38. Adjunct AirwaysCricothyroidotomy

40. References • Trauma Reports Volume 8, No. 1. Jan/Feb 2007. AHC Media, LLC. • Managing the Pediatric Airway in the ED, Pediatric Emergency Medicine Practice. Volume 3, No. 1. January 2006 • Manual of Emergency Airway Management, 3rd Edition. Walls, R. and Murphy, M. 2008.