Anaesthetic management of patient with Maxillofacial injury

1. Anaesthetic management of patient with Maxillofacial injury Moderator – Prof AnjanTrikha Presenter - Priya www.anaesthesia.co.in anaesthesia.co.in@gmail.com

2. Krishna • 25years/male • Student • Resident of Delhi

3. Chief complaints : • Pain and difficulty in chewing × 1 week • Restriction of mouth opening ×1 week

4. History of present illness : • H/O fall from tree one week back • Following which patient developed Pain and swelling on left side of jaw Pain on opening mouth Difficulty in chewing food • No H/O loss of consciousness • No H/O oral, nasal or ear bleed

5. Past history • No H/O any previous GA exposure • No H/O asthma, TB,DM & any drug allergy Personal history : • Non smoker Treatment history : • Inter maxillary wiring was done after trauma Family history : • Not significant

6. General physical examination • Alert, conscious &oriented • No pallor, icterus, clubbing, cyanosis, edema and lymphadenopathy Vitals • PR- 70 beats/min all peripheral pulses palpable • BP – 124/78mm Hg R, upper arm, supine • Weight – 58 kg

7. Airway examination : • Inter incisor gap – wiring present • Length of upper incisor -<1.5 cm • No buck teeth or loose teeth • MMP class – could not be assessed • Upper lip bite – unable to do because of wiring • Thyromental distance = 6.5 cm • Sub mandibular compliance - normal

8. Neck movements • Flexion - adequate • Extension - adequate • Neck thickness normal • No short neck • Nasal patency – equally patent, no deviation or growth seen

9. Respiratory system : • B/L vesicular breath sounds present • No adventitial sounds Cardiovascular system: • First and second heart sound heard, no murmur present

10. Central nervous system : • Higher mental functions normal • No sensory and motor weakness Abdomen : • No visible swelling • No organomegaly

11. Investigations: • Hb – 12gm% • Platelets – 2 lakhs/mm3 • TLC – 8400/mm3 • Na/K – 140/4.2meq/l • Urea/creatinine – 20/0.9mg/dl • LFT - WNL

12. OPG X-ray – fracture in ramus of mandible left side with inter maxillary fixation (IMF) in situ

13. Provisional diagnosis • Fracture mandible left ramus with reduced mouth opening posted for open reduction and internal fixation

14. Surgical procedure planned Open reduction and internal fixation of mandible fracture with plating

15. Summary : • 25 year old male with left mandibular fracture with interdental wiring in situ posted for open reduction and internal fixation

16. Plan • Nasal intubation laryngoscopy guided after removal of wiring

17. Problems : • Nasal intubation – its inherent risks • Sharing of airway • Access to airway • Extubation issues • PONV prophylaxis • Post operative airway obstruction

18. Preoperative prepration • Inform about procedure & risk • Written consent • Premedication aspiration prophylaxis- oral ranitidine antisialogogue – Glycopyrrolatei.m nasal decongestant – xylometazoline drops • Pre op fasting • Wiring was removed on the day of surgery

19. Otprepration • Check machine and emergency equipments • Standard monitoring – ECG, NIBP, pulse oximetry,capnography • iv access secured – extension tubing • Nasal prepration with xylometazoline drops • Softening of nasal tube • Preoxygenation for three minutes

20. Sniffing position • Induction – fent 2mcg/kg, propofol 2-3mg/kg • Mask ventilation assessed ->Vecuronium – 0.1mg/kg • Lubricated 7.5 size nasal RAE tube introduced through rt nostril • Tube guided into glottis under laryngoscopy • Equal air entry confirmed

21. Eye padding, oral packing done • Positioning for surgery • Maintainence – oxygen, air and isoflurane, vecuronium, fentanyl • Antiemetics – dexamethasone and ondensetron • Monitor airway pressure

22. Reversal – neostigmine and glycopyrrolate • Removal of pack and thorough suctioning • Extubation – fully awake, adequate tidal volume, following commands • Postoperative- • Oxygen by face mask • Pulse oximetry • Beware of vomiting aspiration

23. Specific equipments & tools • RAE (nasal) tube, naso pharyngeal airways, warm saline, magill forceps & LA jelly • Fibreopticbronchoscopy, suction apparatus • Lidocainepreprations- 2% viscous,2% injectable solution,10 or 15% spray,4% topical solution • Eye pads, throat pack, small pillows & rolls • Intravenous accesses secured

24. Airway management choices • Fibreoptic guided intubation after i.vinduction,paralysis & IPPV awake with sedation • Blind nasal intubation- awake post induction and paralysis • Light wand guided • Retrograde intubation • tracheostomy

25. Difficult airway: • A clinical situation in which a conventionally trained anaesthesiologist experiences difficulty with mask ventilation, difficulty with tracheal intubation or both

26. Difficult mask ventilation • It is not possible for unassisted anaesthesiologist to maintain the SpO2 > 90% using 100% O2 and positive pressure mask ventilation in a patient whose SpO2 was > 90% before or • It is not possible for the unassisted anaesthesiologist to prevent or reverse signs of inadequate ventilation during mask ventilation

27. Difficult laryngoscopy • It is not possibe to see any portion of the vocal cords after multiple attempts at conventional laryngoscopy Difficult tracheal intubation • A clinical situation in which intubation requires more than three attempts or ten minutes using conventional laryngoscopic techniques

28. Optimal laryngoscopy attempt • Performance by a reasonably experienced laryngoscopist • The use of the optimal sniffing position • The use of OELM • One change in length/type of blade

29. Assessment • History • Specific tests for assessment • Difficult mask ventilation • Difficult laryngoscopy • Difficult surgical airway access • Radiologic / photographic assessment

30. History • Congenital difficult airways • Acquired • Rheumatoid arthritis, Acromegaly, tumors of tongue, larynx • Iatrogenic • radiotherapy, Laryngeal/tracheal/TMJ surgery • Reported previous anaesthetic problems • Database

31. 11 point scoring • Inter-incisor gap : >3cm • Buck teeth + • Length of incisor: <1.5cm • Upper lip Bite • MMP class • Palate: arching / narrowing • TMD: >6cm • Mandibular compliance • Neck length: sufficient • Neck diameter: thin or thick • Neck movement

32. Specific Tests • Mouth opening • Evaluation of tongue size relative to pharynx • Mandibular space • Mobility of the joints • TMJ • Neck mobility

33. Inter-incisor Gap • With maximal mouth opening • Acceptable value > 4 cm • Positive results: Easy insertion of a 3 cm deep flange of the laryngoscope blade < 3 cm: difficult laryngoscopy < 2 cm: difficult LMA insertion • Affected by TMJ and upper cervical spine mobility

34. Evaluation of tongue size relative to pharynx Samsoon-Young’s modification of Mallampati Test • Patient in sitting position • Maximal mouth opening in neutral position • Maximal tongue protrusion without arching • No phonation

35. Class III or IV: signifies that the angle between the base of tongue and laryngeal inlet is more acute and not conducive for easy laryngoscopy • Limitations • Poor interobserver reliability • Limited accuracy

36. 73% 19% 8%

37. Correlation between MMP score and laryngoscopy grade Airway Management, Jonathan Benumof

38. Mandibular space Thyromental distance (Patil test) • Distance from the tip of thyroid cartilage to the tip of mandible • Neck fully extended • Minimal acceptable value – 6.5 cm Significance • Negative result – the larynx is reasonably anterior to the base of tongue • Very low sensitivity-20%

39. Modification to improve the accuracy • Ratio of height to thyromental distance (RHTMD) • Useful bedside screening test • RHTMD < 25 or 23.5 – very sensitive predictor of difficult laryngoscopy Sternomental Distance (Savva Test) • >12.5cm

40. Evaluation of Neck Mobility • Patient is asked to hold the head erect, facing directly to the front  maximal head extension  angle traversed by the occlusal surface of upper teeth • Grade I : > 35° • Grade II : 22-34° • Grade III : 12-21° • Grade IV : < 12°

42. Placing one finger on the patient’s chin  One finger on the occipital protuberance Result • Finger on chin higher than one on occiput  normal cervical spine mobility • Level fingers  moderate limitation • Finger on the chin lower than the second  severe limitation • Angle traversed by the vertex or forehead > 90° from max flexion to max extension is a specific +ve test for atlanto-occipital joint.

43. Mandibular Protrusion Test • Class A: able to protrude the lower incisors anterior to the upper incisors • Class B: lower incisors just reach the margin of upper incisors • Class C: lower incisors cannot reach the margin of upper incisors Significance • Class B and C: difficult laryngoscopy

44. Upper Lip Bite Test • Class I: Lower incisors can bite the upper lip above vermilion line • Class II: can bite the upper lip below vermilion line • Class III: can not bite the upper lip Less inter-observer variability

45. Predictors of Difficult Mask Ventilation • Age > 55 years • BMI > 26 kg/m2 • History of snoring • Beard • Edentulous

46. Difficult LMA Insertion • Mouth opening < 2 cm • Intraoral/pharyngeal masses (e.g. lingual tonsils) Difficult Direct Tracheal Access • Gross obesity • Goitre • Deviated trachea • Previous radiotherapy • Surgical collar

47. Statistical Significance

48. Combination of predictors Wilson Score • 5 factors • Weight, upper cervical spine mobility, jaw movement, receding mandible, buck teeth • Each factor: score 0-2 • Total score > 2  predicts 75% of difficult intubations

49. Quick look back Difficult mask ventilation • Mask fit • Obesity • Age • No teeth • Snoar

50. Difficult laryngoscopy • Look • Evaluate…3.3.2 • Mallampati • Obstruction • Neck movement