1. Applied Anatomy of Airway www.anaesthesia.co.in anaesthesia.co.in@gmail.com

2. Airway? Pathway in which air passes Natural & artificial Natural airway = upper airway Nasal cavity, mouth, pharynx, larynx Trachea,bronchus, bronchial division

4. Anatomical airway

5. Nasal cavity Phylogeniticaly breathing occurs through nose Enables to smell danger, unconditional supply of air while feeding Resistance to air flow twice that of mouth breathing Exercise & respiratory distress mouth breathing is facilitated

6. Nasal Cavity

7. # cribriform plate of ethmoid  csf rhinorhoea Inadverdant placement of NPA, NTT, NG into anterior cranial fossa Chronic nasal intubation cause sinus sepsis

8. Floor of nose & Inferior turbinate Oriented perpendicular to fascial plane Nasal instrumentation should be done perpendicular to this plane Major air passage lies beneath inf. Turbinate Inf. Turbinate limits the size of NTT

9. Vasculature of nose Vasularized sub mucosa Branches of internal carotid artery Nasal packing only way to control bleeding Antero inferior septum- site of epistaxsis Orient leading edge of NTT away from septum

10. Nasal airway calibre change Prior to vasoconstrictorAfter vasoconstrictor

11. Innervation of nasal cavity

12. The Kratschmer reflex leads to bronchiolar constriction upon stimulation of the anterior nasal septum in animals. Similar reflex seen in the postop period when a pt becomes agitated when the nasal passage is packed

13. Mechanism of perforation & submucosal tunneling

14. Tonsils – possible cause of airway obstruction

15. Pharynx Musculofascial tube connects nasal and oral cavity with larynx and esophagus Lacks of bony / cartilagenous frame work Patency maintained by muscle tone only Common site of laceration during traumatic intubation Lead to hematoma, cellulites and total airway collapse

16. Pharynx

17. Sites of airway obstruction

18. Velopharynx – the site of airway obstruction

19. Laryngeal frame work

20. Direct layngoscopic view of larnyx

21. Intrinsic muscles of larynx

22. Normal vocal cord movement

23. Vocal cord Palsies Selmons law : nerve fibers to abductors are vulnerable to injury than adductors Partial b/l RLN palsy leads to stridor Pure adductor palsy, rare clinical entity

24. Cadaveric position of cord Combined b/l RLN & SLN palsy Use of musle relaxants

25. Cricothyroid membrane Extends from inf. border of thyroid cartilage to sup. border of cricoid 9 mm Ht / 22 mm width Sup. 1/3 traversed by sup. Cricoid vessel Laterally by ant. Jugular & inf thyroid veins Midline neck, low 1/3 of CTM – safe site for performing cricothyroidotomy

26. Appropriate position of ETT Endo tracheal tube tip follows tip of the nose position

27. www.anaesthesia.co.in anaesthesia.co.in@gmail.com