airway management with assessment and guidelines 1.pptx

Airway management and clinical implications

1. DIFFICULT AIRWAY ASSESSMENT , MANAGMENT AND GUIDELINES. Presenter :- Dr. Sparsh Singh Department of Anaesthesiolgy Ganesh Das Hospital, Shillong . 1

2. What is an AIRWAY? The passage through which air passes during respiration COMPONENTS OF THE AIRWAY Mouth Nose Pharynx Larynx Trachea Mainstem bronchi 2

3. LARYNX Cartilaginous skeleton held together by ligaments and muscle. Extends from laryngeal inlet(C3-C4) to lower border of cricoid cartilage (C6). Composed of 9 cartilages – Unpaired: Thyroid Cricoid Epiglottis Paired: Arytenoid Corniculate Cuneiform 3

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5. The muscles of larynx are supplied by recurrent laryngeal nerve except cricothyroid which is innervated by external laryngeal nerve. The posterior cricoarytenoid muscles abducts the vocal cords whereas the lateral cricoarytenoid muscles are the principal adductors. 5

6. FUNCTIONS OF AIRWAY Air conduction Warming Filtration Humidification Removal of foreign particles 6

7. WHY ASSESSMENT IS IMPORTANT? Assessment of airway helps in Optimal patient preparation Proper selection of equipment and technique Participation of personnel experienced in the difficult airway management 7

8. What to look for? Facial anomalies like maxillary hypoplasia ( apert syndrome, crouzon syndrome), mandibular hypoplasia( pierre robin syndrome, treacher collins syndrome)/hyperplasia (acromegaly, cherubism ). Temporomandibular joint pathology Anomolies of mouth and tongue like microstomia , ludwigs angina, tumors of mouth and tongue, macroglossia . Problems with teeth – missing or buck tooth Anomaly of the nose like choanal atresia, hypertrophic turbinates , DNS 8

9. Cntd . Pathology of palate like narrow arched palate, cleft defects, soft palate swelling and hematomas. Pathology of pharynx – hypertrophic tonsils and adenoids, tumors and abscesses. Pathology of larynx – epiglotitis , laryngomalacia , granuloma, stenosis, inflammatory edema. 9

10. Causes for difficulty in mouth opening Ankylosing spondylitis Rheumatoid arthritis TMJ fixity Scleroderma Local acute infection Localized tumor Circumoral burns with scarring 10

11. Causes for difficulty in head extension Ankylosing spondylitis Rheumatoid arthritis Cervical spondylitis or fusion Scleroderma Cystic hygroma Large hydrocephalus and encephalocele 11

12. AIRWAY ASSESSMENT A preanesthetic airway assessment is mandatory before every anesthetic procedure. Several anatomic and functional maneuvers can be performed to estimate the difficulty of endotracheal intubation. Mouth opening – an incisor distance of 3 cm or greater is desirable in an adult. Mallampati classification – it examines the size of tongue in relation to oral cavity. 12

13. MALLAMPATI CLASSIFICATION Class I: entire palatal arch, bilateral faucial pillars is visible down to the bases of the pillars Class II: upper part of faucial pillars and most of the uvula are visible. Class III: soft and hard palates are visible Class IV: only hard palate is visible Class III and IV → Difficult to Intubate 13

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15. Thyromental distance – distance between the mentum and the superior thyroid notch. A distance greater than 3 fingerbreadths is desirable. Neck circumference – greater than 17 inches is associated with difficulties in visualization of glottic opening. 15

16. Hyomental distance – grade 1 - >6 cm grade 2 – 4 – 6 cm grade 3 - <4 cm (usually associated with impossible laryngoscopy and intubation) Sternomental distanc e – measured with head in full extension and mouth closed. A distance of <12.5 cm predicts a difficult laryngoscopic intubation. 16

17. DIFFICULT AIRWAY A clinical situation in which a conventionally trained anesthesiologist experiences difficulty with mask ventilation, difficulty with tracheal intubation or both. 17

18. DIFFICULT MASK VENTILATION It is not possible for the unassisted anesthesiologist to maintain SPO2>90% using 100% O2 and positive pressure mask ventilation in a patient whose SPO2 was > 90% before anesthetic intervention and/or It is not possible for the unassisted anesthesiologist to prevent or reverse signs of inadequate ventilation during positive pressure mask ventilation 18

19. SIGNS OF INADEQUATE MASK VENTILATION Absent or inadequate chest movement. Absent breath sounds. Gastric air entry or dilatation. Cyanosis. Haemodynamic changes due to hypoxia or hypercarbia . Decreasing oxygen saturation. Absent or inadequate exhaled CO2 19

20. PREDICTORS OF DIFFICULT MASK VENTILATION B EARDED O BESE (>26KG/M2) AND U PPER AIRWAY OBSTRUCTION N O TEETH (EDENTULOUS) E LDERLY (>55 YEARS) S NORERS OTHER CRITERIA:- MOANS 20

21. HAN’S SCALE OF DIFFICULT MASK VENTILATION I. VENTILATED BY MASK II. VENTILATED BY MASK WITH ORAL/NASAL AIRWAY WITH / WITHOUT MR III. DIFFICULT MASK VENTILATION WITH/ WITHOUT MR IV. UNABLE TO MASK VENTILATE WITH/WITHOUT MR 21

22. DIFFICULT LARYNGOSCOPY It is not possible to visualize any portion of the vocal cords with conventional laryngoscope (ASA definition). 22

23. DIFFICULT ENDOTRACHEAL INTUBATION Proper insertion of the tracheal tube with conventional laryngoscopy requires more than 3 attempts or more than 10 minutes. 23

24. INTUBATION ATTEMPT An intubation attempt is defined as “Intubation activities occuring during a single continuous laryngoscopy maneouver ”. Thus, even if several attempts were made to place an ETT during the course of a single laryngoscopy, it would be counted as a single intubation attempt. 24

25. BEST ATTEMPT LARYNGOSCOPY Laryngoscopy performed by reasonably experienced laryngoscopist with the patient in optimal sniff position having no significant muscle tone and the laryngoscopist has an option of change of blade type and length . 25

26. PREDICTORS OF DIFFICULT LARYNGOSCOPY AND TRACHEAL INTUBATION DIRECT ASSESSMENT Reduction of a-o extention : 1. No reduction 2. 1/3 rd reduction 3. 2/3 rd reduction 4. Complete reduction 2/3 rd or complete reduction is a clear pointer to difficult rigid laryngoscopy. 26

27. Delikan’s test – assesses movement of occiput on atlas during extension. Prayer sign - The patient cannot bend their fingers backwards while approximating palms. Seen in long term juvenilediabetic patients due to stiff joint syndrome. 27

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29. Palm print sign : Patient’s fingers and palms painted with blue ink and pressed firmly against a white paper. 0 - all phalangeal areas visible 1 - deficient interphalangeal areas of 4th and 5th digits 2 - deficient interphalangeal areas of 2nd to 5th digits 3 - only tips seen 29

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31. ASSESSMENT OF TMJ FUNCTION TM joint exhibits 2 functions: Rotation of the condyle in the synovial cavity. Forward displacement of the condyle. First movement is responsible for 2-3cm mouth opening and the second is responsible for further 2-3cm mouth opening. 31

32. SUBLUXATION OF THE MANDIBLE Index finger is placed in front of the tragus & the thumb is placed in front of the lower part of the mastoid process. Patient is asked to open his mouth as wide as possible. Index finger in front of the tragus can be indented in its space and the thumb can feel the sliding movement of the condyle as the condyle of the mandible slides forward. 32

33. CALDER TEST The patient is asked to protrude the mandible as far as possible. The lower incisors will lie either anterior to, aligned with or posterior to the upper incisors . The latter two suggest reduced view at laryngoscopy. 33

34. LEMON ASSESSMENT L - Look externally (facial trauma, large incisors, beard, large tongue) Evaluate 3-3-2 rule 3 - Inter incisor gap 3 - Hyomental distance 2 - Distance between thyroid cartilage and floor of the mouth. M – Mallampati grade O - Obstruction (epiglottitis, quinsy) N - Neck mobility. 34

35. WILSON SCORING 5 factors – Weight Upper cervical spine mobility Jaw movement Receding mandible Buck teeth Each factor: score 0-2 Total score < 5 – Easy laryngoscopy , 6 to 7 - Moderate difficulty, > 7 - Severe difficulty 35

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37. RULE OF 1-2-3 1 finger breadth for subluxation of mandible. 2 finger breadth for adequacy of mouth opening. 3 finger breadth for hyomental distance. In emergency situation, above test can be rapidly performed within 15sec to assess the TMJ function , mouth opening and SM Space. Significant difficulty in 2 or more of these components requires detailed examination. 37

38. RULE OF THREE 3 finger in the interdental space. 3 finger between mentum and hyoid bone. 3 finger between thyroid cartilage & sternum 38

39. X-RAY X-Ray neck (lateral view) • Occiput - C1 spinous process distance < 5mm. • Increase in posterior mandible depth > 2.5cm. • Ratio of effective mandibular length to its posterior depth <3.6. • Tracheal compression. 39

40. FOUR D’s OF DIFFICULT AIRWAY ASSESSMENT Dentition (prominent upper incisor, receding chin) Distortion(edema, blood, vomitus, tumor, infection) Disproportion(short chin to larynx distance, bull neck) Dysmobility (TMJ and cervical spine pathologies) 40

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42. What doe s AS A 22 say?

43. Three ‘nonsurgical’ techniques to establish a patent airway If a ‘best e ffort’ at any of the th r ee lifelines is unsucces s ful, this m andates spira l movement inward to the next lifeline Failure to establish patent airway after best effort at all three lifelines culminates in arrival at the central zone to initiate ‘CICO rescue’FONA

44. AIDA A r ecommendations Assessment None of the available tests are reliable Always be prepared for difficult airway Preparation Pre-oxygenation and peri-intubation oxygenation Head-up position 20 Tidal volume breath for 3 mints 8 vital capacity breaths for 60 secs 10 L/min of O2 Target ETO2 > 90% & N2 < 4% C P A P & PSV Apnoeic Oxygenation through 15L/min Nasal O2 THRIVE

45. Laryngoscopy and Intubation – failed Call for help, continue oxygenation 15L/min Maximum 2 more attempts Repeat only if SpO2 > 95% Change plans after first attempt, optimise position etc Blind insertion in grade 3b & 4 is not recommended Confirmation of intubation

46. SAD – 2 nd generation High sealing pressure Max 2 attempts Only 4.2% of devices inserted successfully at the third attempt.

47. RESCUE STRATEGIES: Continue nasal Oxygen 15L/min One final attempt at mask ventilation Use optimal technique and adjuncts, Ensure complete neuromuscular blockade,

48. p VENTILATION FAILURE PRECEEDS OXYGENATION FAILURE AIDAA recommends proceeding to emergency cricothyroidotomy when there is CVF, EVEN IF oxygenation is maintained and not when hypoxaemia sets in. CAL L FOR ADDI T IONA L HELP CONTINUE ATTEMPTS AT OXYGENATION THROUGH UPPER AIRWAY 37 What should be the Trigger?

49. CALL FOR AD D ITIO N AL HELP Complete ventilation failure (CVF ) Situation where intubation, ventilation using SAD and face mask have all failed after giving the best attempt, even if oxygenation may be maintained

50. Position Landmark – cricothyroid membrane Laryngeal Handshake

51. Di r ect / V L (max 3+1 attem pt) 2 nd generation SAD Change device or size (max 3 attempts) Oxygenate & ventilate If facemask ventilation impossible, paralyse Final attempt of facemask ventilation Use 2 person technique Declare CICO Surgical Cricothyroidectomy

52. 2008 DAS 2015 DAS 2016 AIDAA CICV CICO CVF Terminologies

53. Obstetrics Incidence of difficult airway 1 in 224, 8 times more Always full stomach Decreased OES pressure Increased chance of aspiration Rapid desaturation Assess the front of neck access Priority is for mother’s safety

54. HELP, RSI, One more attempt in optimum condition Gentl e IPPV wit h AP L valve closed t o < 20 cm H2O Release Cricoid pressure partial or complete

55. Mother sustains Cardiac arrest: Perform CPR with left uterine displacement Perform Caesarean delivery within 4 mins of cardiac arrest

56. One more attempt - Max 2 attempts Fina l atte m pt ( 3 rd ) s h ould be allowed only by an a naes t he s iol o gist with paediatric experience 43

57. CVF is very rare Technical difficulty of locating the correct anatomical structures Emergency rescue should not be delayed till there is desaturation Needle cricothyrotomy / transtracheal needle puncture should be replaced with tracheostomy within 40 mins

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59. Game plan Assess airway Perioxygenate SpO2 < 95% as cut off for escalating airway interventions Limit the no of intubation & SAD attempts as per the guidelines Never hesitate to call for additional help CVF the trigger for Emergency Crico (Stab – twist – bougie – tube) Have a Post Procedural Plan and Standard reporting UADA Never use a guideline and a equipment for the first time in crisis Follow a guideline which best fits as per your limitations Preparedness and rehearsal are the key to overcome crisis

60. REFRENCES Miller's Anesthesia 9 th edition Clinical Anesthesiology , 5th Edition, G . Edward Morgan, Jr., Maged S. Mikhail, Michael J. Murray Rashid M Khan Airway management, 7 th edition