AIRWAY ASSESSMENT & THINKING BEYOND ANATOMY (2).pptx

AIRWAY

1. AIRWAY ASSESSMENT & THINKING BEYOND ANATOMY Dr Swati Soni Consultant Intensivist SDMH

2. Why airway assessment Optimal patient preparation Proper selection of equipment and technique Participation of personnel experienced in difficult airway management.

3. Safe airway management airway evaluation identification of the difficult airway assessment of other clinical factors selection of the likely most successful plan of action reasonable alternative plan

4. DIFFICULT AIRWAY Difficult airway is an airway for which an experienced practitioner anticipates or encounters difficulty with face mask ventilation, tracheal intubation, supra glottic airway use or recognizes the use of surgical airway. Predictors of airway management can be caterogerized as anatomical and physiological. Obesity is significant predictor of airway difficulty because of combination of anatomical and physiological factors. ASA 2022 GUIDELINES

5. According to the  2022 American Society of Anesthesiologists Practice Guideline for Management of the Difficult Airway , difficult airways can be further divided into seven types: difficult facemask ventilation, difficult laryngoscopy, difficult supraglottic airway ventilation, difficult or failed tracheal intubation, difficult or failed tracheal extubation , difficult or failed invasive airway, and inadequate ventilation. The worst case situation is "failure to intubate and ventilate", and up to one-third of anesthesia-related deaths are due to failure to intubate and ventilate, so this deserves our utmost attention. The occurrence of a difficult airway can lead to tracheal or esophageal injury, aspiration, and severe hypoxemia, which can cause irreversible brain damage and lead to death.

6. How to assess History ( previous history of difficult intubation/ difficult extubation , history of neck surgery/ burns, history of concurrent diseases, history of GERD, recent meals) General examination (morbidly obese/ pregnant/ dentition- prominent upper incisor, receding JAW/ distortion- edema, blood, tumor, infection/ disproportion/ dysmobility - cervical spi n e , TM joint.) Specific tests / indices.

7. The only validated airway assessment method for a critical ill patient is the MACOCHA score. MACOCHA : M allampati class III or IV, A pnea syndrome (obstruction), C ervical spine limitation, O pening of mouth<3 cm, C oma, H ypoxemia, A nesthetist not trained

8. DIFFICULT BAG AND MASK VENTILATION radiation(head and neck)/ restriction(poor lung compliance) obesity/ obstruction of upper airway/ obstructive sleep apnoea mask seal age over 55 year no teeth

9. DIFFICULT INTUBATION BY DIRECT LARYNGOSCOPY An airway exam should include an assessment of mouth opening, dentition, thyromental distance, neck circumference, Mallampati scor e and cervical spine mobility. The mnemonic, LEMON, is often used to evaluate an airway. L: Look externally for facial trauma/ large incisors, large tongue E: Evaluate 3-3-2 rule M: Mallampati >3 O: Obstruction ( epigottitis, peritonsillar abscess) N: Neck mobility restricted. Indicators such as a diminished mouth opening of lesser than 3 fingers, a large neck, a short thyromental distance of lesser than 3 fingerbreadths, Mallampati 3 or 4, or limited neck extension should alert the provider of a possible difficult airway and prompt for proper preparation.

10. DIFFICULT CRICOTHYROIDOTOMY SURGERY MASS(HEMATOMA/ ABSCESS) ACCESS OR ANATOMY(OBESITY/ POOR LANDMARKS) RADIATION (TISSUE SCARING/ DEFORMITY) TUMOR

11. DIFFICULT SUPRAGLOTTIC AIRWAY PALCEMENT RESTRICTED MOUTH OPENING OBSTRUCTION DISRUPTED OR DISTORTED AIRWAY SHORT THYROMENTAL DISTANCE

12. Established high-end methods of difficult airway assessment Preoperative endoscopic airway examination (PEAE) Various visible-light endoscopes, such as the video laryngoscope, visual light sticks, transnasal flexible endoscopic laryngoscope and fiberoptic bronchoscope, can help anesthesiologists view airway anatomy directly. The use of these endoscopes can dramatically reduce the rate of failed intubation and laryngeal/airway trauma.

13. Imaging X-ray, ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI) have been widely used to diagnose difficult airway.

14. Some of the problems we can't ignore with X-rays, CT and MRI are their radiation, inconvenience and high cost, but not with ultrasound. Ultrasonography can image not only some anatomical structures also visible by video laryngoscopy, such as the tongue, epiglottis, and glottis, but also some anatomical structures that are not visible with laryngoscopy, such as the hyoid bone, cricoid cartilage, and soft tissues of the neck. In fact, the diagnostic index and AUC of ultrasound were similar to those of CT and X-ray in predicting difficult airways, and the diagnostic value of all three was much better than the modified Mallampati score

15. AIRWAY IN ICU (OTHER THAN ANATOMY) is oxygenation adequate???? if oxygen saturation falling despite adequate oxygenation maneuvere, this is a failed airway, even before any intubation attempt. Eg:- difficult bag mask ventilation, can’t intubate, cant ventilate scenario. severely hypoxemic patients ( pneumonia/ ARDS). critically ill patients with poor functional residual capacity.

16. Is a forced to act immediately scenario present:- if there is rapid dynamic airway deterioration eg. consider a morbidly obese patient with severe status asthamticus who is combative and fatigued, oxygen saturation falling to 80s despite maximal therapy- a prompt decision to give RSI drugs and create the best possible situation for a single best attempt at tracheal intubation. another example is patient with rapidly worsenin g of airway swelling due to anaphylaxis- partial airway obstruction.

17. Are significant anatomic barriers identified???? RSI may be contraindicated when significant anatomic barriers present and laryngoscopy is predicted to fail. complete upper airway obstruction, loss of facial or oropharyngeal lamndmarks, facial trauma which significantly distorts the upper airway anatomy- these are few absolute contraindications of RSI, a surgical airway is needed.

18. Are there physiologic derangements that render the patient intolerant to apnoea or at risk of peri intubation cardiovascular collapse??? A patient who is at risk for rapid oxygen desaturation. A patient who presents with shock or with profound refractory hypotension may be dependent on sympathetic drive and remaining myocardial function to maintain perfusion. induction agents induced vasodialation and myocardial depression my result in complete loss of circulation with in minutes. patients in shock have six fold increased risk of peri intubation arrest. similiarly a patient with metabolic acidosis is at risk for worsening their acidosis once the respiratory compensation is removed by NMA.

19. what if there is increased ICP????? The techniques and medications used in airway management may increase ICP through several mechanism, include reflex sympathetic response to laryngoscopy.

20. is patient candidate for neuromuscular blockade????

21. AI to predict difficult airway The potential of AI in healthcare is enormous. At the same time, the birth and rapid development of technologies such as face recognition and analysis have made it possible to apply them to predict difficult airways.  nowdays new AI generated apps are available which use few patient patient characterstics like history, facial anatomy, surgical procedure and vitals signs and categorize airway basic or advanced based.

22. THANK YOU