Difficult airway

difficult airway

1. DIFFICULT AIRWAY PRESENTED BY:- Dr Pratyush Kumar Dr Tapas Ranjan Behera Dr Deepak Bharaj

2. DEFINITION The clinical situation in which a conventionally trained anaesthetist experiences difficulty with masked ventilation, difficulty with tracheal intubation or both.

3. Difficult ventilation : The inability of a trained anaesthetist to maintain oxygen saturation >90 using face mask for ventilation and 100% inspired oxygen, provided that the pre-ventilation oxygen saturation level was within the normal range. Difficult intubation: More than 3 attempts Longer than 10mins Failure of optimal best attempt

4. CAUSES

5. ANAESTHESIOLOGIST: Inadequate preoperative assessment Inadequate equipment preparation Inexperience Poor technique EQUIPMENT: Malfunction/ Unavailability PATIENT: Congenital and acquired causes

6. CONGENITAL CAUSES: Down’s syndrome Pierre Robin Syndrome : Micrognathia , Macroglossia , Cleft soft palate Goldenhar’s Syndrome: auricular and ocular defects, molar and mandibular hypoplasia, occipitalization of atlas ACQUIRED CAUSES: Infections: Supraglottitis , Croup, Abscess, Ludwig’s angina Arthritis : Rheumatoid Arthritis, Ankylosing Spondylitis Tumour Trauma Obesity Acute burns Acromegaly

7. ASSESSMENT OF DIFFICULT AIRWAY History General physical examination Specific test for assessment: Difficult mask ventilation Difficult laryngoscopy Difficult surgical airway access Radiologic assessment

8. HISTORY Congenital airway abnormalities Acquired conditions like rheumatoid arthritis, benign and malignant tumours of longue, larynx etc Iatrogenic conditions like oral/pharyngeal radiotherapy, laryngeal/ tracheal surgery, TMJ surgery Reported previous anaesthetic problems

9. GENERAL EXAMINATION Adverse anatomical features e.g. small mouth, receding chin, high arched palate, large tongue, morbid obesity Mechanical limitation: Reduced mouth opening Post-radiotherapy fibrosis Poor cervical spine movement Poor dentition: prominent/ loose teeth Orthopaedic/ orthodontic equipment Patency of nasal passage

10. AIRWAY EVALUATION Evaluation of tongue size relative to pharynx Mandibular space Assessment of glottic opening Mobility of the joints: TMJ Neck mobility(cervical)

11. AIRWAY ASSESSMENT INDICES Individual indices Group indices: Wilson’s score Benumof’s analysis Saghei & safavi test Lemon assessment Radiological indices

12. INDIVIDUAL INDICES Mallampati test

13. Hyomental distance Distance between mentum and hyoid bone Grade I: >6cm Grade II: 4-6cm Grade III: <4cm Grade III denotes impossible laryngoscopy & intubation

14. Sternomental distance Distance from upper border of the manubrium to the tip of mentum , neck fully extended mouth closed Minimal acceptable value- 12.5cm Single best predictor of difficult laryngoscopy and intubation

15. Inter-incisor gap Inter-incisor distance with maximal opening Normal value >5cm / admits 3 fingers. Significance: <3cm : difficult laryngoscopy <2cm : difficult Laryngeal Mask Airway(LMA) insertion Affected by TMJ and upper cervical spine mobility

16. Mandibular protrusion test

17. GROUP INDICES

18. Wilson score

19. Lemon assessment L- look externally Obesity Short neck Prominent upper incisors(Buck teeth) Facial trauma Macroglossia

20. E- Evaluate 3-3-2 rule 3 fingers in mouth 3 fingers fit from mentum to hyoid cartilage 2 fingers fit from the floor of the mouth to the top of thyroid cartilage.

21. M- Mallampati score Score of 3-4 suggest higher risk O- Obstruction Severe angioedema Supraglottic swelling Tumours N- Neck mobility Atlanto -occipital angle Angle <21 degrees suggests higher risk

22. MANAGEMENT OF DIFFICULT AIRWAY

23. Difficult airway cart

24. THANK YOU