Flashcards in Chapter 2 - Airway And Ventilatory Management Deck (30)
What is the definition of a definitive airway?
A cuff inflated below the level of the vocal cords, connected to an O2-enriched source of ventilation, and secured with tape
What 2 things do you do if there are gastric contents in an airway?
Suction (Yankauer) and rotate patient to lateral position
What 3 things do you see in MaxFax fractures? What is the main concern in a bilateral mandibular fracture?
3 things = Haemorrhage, dislodged teeth, increased secretions.
Bilateral mandibular fractures can cause loss of normal airway structural support, leading to airway obstruction when supine.
Blunt/penetrating neck injuries can disrupt larynx/trachea - what is the main concern?
Obstruction or bleeding into the tracheobronchial tree, necessitating a definitive airway (even if obstruction is partial)
What are the 3 signs of (albeit rare) larynx fracture? What is the treatment? What other main structures can be damaged?
Hoarseness, Subcut Emphysema, and a palpable fracture.
Try flexible endoscopic intubation; if it fails, do tracheostomy - but even this may be difficult, so cricothyroidotomy may be lifesaving.
Damage may occur to oesophagus/carotids/jugular veins.
Assuming no alcohol, when assessing behaviour, agitation = ? and obtundation = ?
When listening, stridor/snoring = ?, hoarseness = ?
Agitation = Hypoxia
Obtundation = Hypercarbia
Stridor/snoring = Partial pharynx/larynx occlusion
hoarseness = Laryngeal obstruction
What are the causes of decreased ventilation?
1. Airway obstruction,
2. Pre-existing pulmonary disease
3. Intracranial injury
4. Chest trauma (causing pain and therefore rapid shallow breathing)
5 C-spine injury sparing phrenic nerves, which causes abdominal breathing and paralysis of intercostal muscles.
What are 2 signs of decreased ventilation? Why is pulse oximetry unhelpful when assessing ventilation?
1. Asymmetric chest movements (eg flail chest)
2. Decreased air entry on one or both sides
Pulse Oximetry measures oxygenation/perfusion, but not ventilation, for which you need end-tidal CO2.
What does LEMON stand for, and what is it?
It's the way to assess airway difficulty.
L = Look for C-spine injury, severe arthritis, obesity, overbite, significant maxfax trauma etc
E = Evaluate 3-3-2 rule
M = Mallampati
O = Obstructive conditions (eg epiglottitis, peritonsillar abscess)
N = Neck mobility - patients in a hard spinal collar can't move neck at all, therefore intubation is hard.
What are the Mallampati classifications?
I = Soft palate/uvula/fauces/pillars visible; II = soft palate/uvula/fauces visible; III = soft palate and base of uvula visible; IV = Hard palate only
What is the 3-3-2 rule?
To allow simple intubation, you need:
3+ finger breadths between the patient's top and bottom incisor teeth (with mouth open)
3+ finger breadths between the hyoid bone and chin (with mouth closed).
2+ finger breadths between thyroid notch and floor of mouth (with mouth closed).
What equipment is needed when preparing for the arrival of a patient with a possible obstructed airway?
Suction, O2, OP/NP airways, bag-mask, laryngoscope, bougie, extra-glottis devices, surgical/needle cricothyroidotomy kit, ET Tube, pulse oximetry, CO2 detection device, drugs
Why shouldn't you put an OP airway in a conscious patient?
Gagging --> Aspiration.
What's the important thing to remember about putting an OP airway in children?
Don't rotate it 180 degrees, as you can damage the mouth/pharynx.
Name 4 types of Extra/Supraglottic devices.
Laryngeal Mask Airway (LMA), Intubating LMA (ILMA), Laryngeal Tube Airway (LTA), or Multilumen Oesohageal Airway.
What are the three types of airway? What are the Airway, Breathing and Disability criteria for needing them?
3 types = orotracheal, nasotracheal or surgical (cricothyroidotomy or tracheostomy).
Airway criteria = Inability to maintain patent airway (eg inhalation injury, facial fracture, retropharyngeal haematoma)
Breathing criteria = Inadequate oxygenation by face mask, or apnoea.
Disability = GCS < 8, sustained seizure or to protect against aspiration.
What are two main complications of NASOtracheal airways?
Sinusitis and pressure necrosis. And if patient is apnoeic, orotracheal intubation is mandatory.
What 4 types of fracture are relative contraindications to NASOtracheal intubation?
Facial, frontal sinus, basilar skull and cribriform plate fractures (as evidenced by raccoon eyes, battle's sign, rhinorrhoea or otorrhoea).
What manoeuvre helps to visualise the vocal cords?
Backward, Upward, Rightward Pressure (BURP) on thyroid cartilage ( you need extra hands to do this!).
When passing a Bougie blindly, should the angled tip be positioned anteriorly or posteriorly?
How is tracheal position confirmed when passing it?
Confirm position by feeling a 'click' of the distal tip rubbing along the cartilaginous tracheal rings (felt in 65-90% of bougie placements).
What 3 checks should be made to confirm an ET Tube is in the right place?
What complications should you look for once ventilating?
1. Auscultate for equal breath sounds bilaterally plus NO borborygmi (stomach gurgling sounds).
2. CO2 detection device
Look out for tension pneumothorax (due to positive pressure) and gastric distension, which can cause the stomach to press on the vena cava, causing hypotension and bradycardia.
What diameter ET Tube should be used to pass over a bougie? If the tube gets stuck at the epiglottic folds, what manoeuvre should be carried out?
Withdraw the tube slightly, and turn it 90 degrees before advancing.
What are the 10 steps of Rapid Sequence Induction?
1. Plan in case of failure! (surgical airway kit nearby)
2. Ensure suction and positive pressure ventilation are ready.
3. Preoxygenate with 100% O2.
4. Apply pressure over cricoid.
5. Administer induction agent (e.g. Etomidate 0.3mg/kg) or sedate.
6. Administer 1-2mg/kg succinylcholine (or equivalent)
8. Inflate cuff, auscultate, check end CO2.
9. Release cricoid pressure.
10. Ventilate and CXR to confirm position.
What is the advantage of Etommidate?
What is the main thing to watch out for when using Succinylcholine?
Etomidate doesn't affect BP or intracranial pressure (but can suppress adrenals).
Succinylcholine can cause hyperkalaemia (so use with caution in burns/electrical/crush injuries, or CKD).
What are 4 indications for a surgical airway?
1. Failed ET Tube
2. Oedematous glottis
3. Fractured larynx
4. Oropharyngeal haemorrhage.
What size cannula should be used in Needle Cricothyroidotomy? How long can this airway last and why? What flow rate of O2 should be used?
12-14 gauge (adults) or 16-18 (children).
It lasts 30-45 minutes as there is gradual accumulation of CO2.
Use 5-7Lmin as persistent glottis obstruction can cause an increase in pressure, leading to pulmonary rupture and tension pneumothorax.
What are 7 complications/side-effects of a Needle Cricothyroidotomy?
Aspiration (of blood), Oesophageal laceration, Haematoma, Thyroid Perforation, Pneumothorax, Subcut Emphysema, Poor ventilation.
What is the lower age limit for Surgical Cricothyroidotomy and why?
12 years old; it can damage the cricoid cartilage which is the only support for the upper trachea in young children.
What are 5 complications of a Surgical Cricothyroidotomy?
Aspiration, False Passage, Laryngeal/Subglottic Stenosis, Laceration of trachea/oesophagus, Vocal cord paralysis.