1. Airway Management

2. Airway Anatomy
Airway Assessment
Airway Devices
Difficult Airway
Surgical Airway
Complications

3. Airway Anatomy
Fig The Larynx

4. Airway Assessment

5. Risk factors for Difficult airway
Mouth opening less than 4cm
Thyromental distance less than 6cm
Mallampati Class III or IV
Neck movements less than 80%
Limited jaw protrusion
Body Weight > 110kg
History of difficult intubation

7. Structured Airway Evaluation

9. Airway Devices

11. Bag Mask Ventilation (BMV)

13. Difficulties with BMV Lack of proper seal Facial trauma
Limited chest wall movement e.g. distended abdomen
Poor neck stability
Obesity
Airway obstruction

14. Laryngeal Mask Airway (LMA)

15. Indications Alternative to face mask for maintaining airway
Suitable in elective procedures where tracheal intubation is not necessary
Known or unexpected difficult airway
Establishing airway in unconscious patient with absent glossopharyngeal and laryngeal reflexes when intubation not possible

16. Contraindications
Patients with aspiration risk e.g. Not fasted, obese, pregnant
Patients with decreased pulmonary compliance e.g. Pulmonary fibrosis

17. Endotracheal Intubation

18. The Decision to Tube...
Is there failure of airway maintenance or protection?
Is there failure of ventilation?
Is there failure of oxygenation?
Is there an anticipated need for intubation (ie, what is the expected clinical course)?

19. Indications Surgery on head, face, neck, shoulder or thorax
Patients at risk of aspiration/regurgitation
Muscle paralysis
Lengthy surgery
Major abdominal surgery
Failure of mask anaesthesia
Abnormal positions
Limited airway access
Morbid obesity

20. Positioning

21. Verifying Placement ET CO2 Auscultation Chest movement Direct vision
Vital signs
Condensation in tube
Tube markings
Movement of reservoir bag
Pulse oximetry
Fiberoptic bronchoscopy

22. The Difficult Airway
“One that requires multiple attempts, multiple operators, multiple devices, excessive lifting force, external laryngeal manipulation, or is performed with an inadequate glottic view”

23. The LEMON Law Look externally: body habitus, obesity, facial trauma
Evaluate (3-3-2 rule):
3:mouth opening > 3 fingers
3: Thyromental distance > 3 fingers
2: Superior laryngeal notch >2 fingers

25. Mallampati score
Obstruction/Obesity
Neck mobility e.g can be placed in “sniffing” position

26. Difficult BMV Mask seal e.g. anatomy, facial hair, vomitus
Obstruction/Obesity
Age
No teeth
Stiffness e.g. poor lung compliance

29. Fig. 9.5 Cannot intubate, cannot ventilate algorithm
Transtracheal jet ventilation (TTJV) or low pressure ventilation
Fig. 9.5 Cannot intubate, cannot ventilate algorithm

30. Anatomical Considerations in Children
The position of the larynx is higher and more anterior than in adults, hyperextension of the neck may worsen obstruction of the upper airway.
Airways more susceptible to obstruction from edema, mucous plugs, or foreign body
Larger occiput causes passive flexion of the cervical spine, a rolled towel under the child's upper shoulders keeps the chin tilted up
Tongue is relatively larger compared to the oral cavity in the child than in the adult and can fall back against the hypopharynx in a child with a decreased level of consciousness

31. Anatomy of Cricothyroid space

32. Surgical Airway
Needle/catheter cricothyroidotomy

33. Minitracheostomy

34. Complications
Barotrauma (subcutaneous emphysema, pneumothorax, pneumomediastinum, pneumopericardium)
Breakage or bending of the needle
Kinking, dislodgement, or breakage of the catheter
Perforation of the esophagus or other structures in the neck or thorax
Bleeding at the insertion site or into the trachea, causing obstruction
Expiratory obstruction
Hypoventilation with hypercapnia and acidosis
Sore throat
Infection

35. Emergency Cricothyroidectomy

36. Extubation Criteria CNS criteria Ventilation and oxygenation criteria
The patient should be awake and cooperative
Protective reflexes are present (cough, gag, and swallow)
Ventilation and oxygenation criteria
The patient is breathing spontaneously
The respiratory rate is less than 25/min
The tidal volume is at least 5 ml/kg
The vital capacity is at least 15 ml/kg
The arterial pH is greater than 7.35
The arterial PaCO2 is less than or equal to 50 mmHg
The oxyhemaglobin saturation is greater than or equal to 90% when the FiO2 is less than or equal to 0.4
Neuromuscular criteria
The patient has unassisted head lift greater than 5 s
Full reversal from neuromuscular relaxant drug blockade has been documented by testing with a nerve stimulator

37. Airway Emergencies Pharyngeal Muscle Weakness
Loss of pharyngeal tone → obstruction
Due to residual neuromuscular blocks, anesthetic effect or opoids
Managed with jaw thrust + CPAP
Consider reversals if persistent

38. Laryngospasm More common in paeds Risk factors
Inadequate anaesthesia
Premature extubation
Semicomatose state
Aspiration
NGT
Positive pressure ventilation ± succinylcholine (0.1 mg/kg IV)

39. Aspiration Risk factors
Emergency
Abdominal surgery
Pregnancy
Obesity/recent meal
Delayed gastric emptying e.g. Hx reflux
Preventative measures include: antacids, RSI, ET
Managed with 100% O2, suction, PPV/PEEP

40. Hypoxia
Inadequate O2 supply