Anaesthetic Vivas - Airway Mx

Front 1

Airway Assessment - Difficult Intubation

Back 1

MP score
Thryomental Distance
Neck extension
mouth opening / interincisor distance
dentition
airway swelling/mass/deviation
OSA
Neck circumference

Front 2

Airway Ax - Difficult BMV

Back 2

"OBESE"

Obese = BMI > 26
Bearded
Elderly (Age > 55)
Snoring (OSA)
Edentulous

Front 3

AFOI

Back 3

I would prepare theatre with...
(diff intubation trolley, FOB/Tube - ie, bullet-tipped tube size 7, etc, oral airway Berman/Ovassapian, appropriate assistance, +/- 2nd anaesthetist if possible running sedation, ie, remifentanil low dose)

I would prepare patient with...
- monitoring
- premed (glyco...fentanyl)
- topicalisation (devilbiss, 4% lignocaine up to 9mg/kg, or cophenylcaine spray, or Mucosal atomisation device, etc....)... end points are loss of gag and change in voice.

I would then perform FOB with the surgeon's in theatre (with the patient sitting, lying, etc).

I would confirm correct placement with visual, and ETCO2, then induce GA.

Front 4

Gas Induction

Back 4

I would prepare theatre with....
In addition to my usual equipment I would have.. (difficult intubation trolley, VDL)

Monitoring...

I would topicalise the oropharynx as able.

I would have senior assistance, and the surgeon's scrubbed in theatre.

I run a low dose remifentanil infusion (0.05-0.1mcg/kg/min), and induce with sevo/100% O2.

Front 5

RSI

Back 5

In addition to my usual monitoring/equipment and assistance, I would have
- difficult intubation trolley
- 2nd person for cricoid pressure.

I would preoxygenate until ET-O2 was adequate, then induce with propofol/sux (+/- fentanyl). Ask assistant to place cricoid pressure on LOC, intubate, confirm position, and that's it.

Front 6

DAS Difficult Airway Algorithm

Back 6

Standard induction (non-depolarising MR)

* Plan A - initial intubation plan (Direct laryngoscopy)
No more than 4 attempts, trying different position, operator, laryngoscope.
*Plan B - secondary intubation plan
iLMA/LMA, FOB, etc
*Plan C - Oxygenation
Face mask ventilation, 2hands, OPA/NPA
*Plan D - CICV
Rescue technique with LMA
Cricothyroidotomy (needle or surgical).


RSI
*Plan A - initial intubation plan (direct laryngoscopy)
NO more than 3 attempts at intubation.
**NO Plan B in RSI
*Plan C - Oxygenation
FM ventilation as required
*Plan D - CICV
LMA rescue technique
Cricothryoidotomy.

Front 7

CICO

Back 7

- Sats falling or < 90%?
- failure to intubate x 2
- failure of supraglottic airway

Call Code Blue and prepare for Cricothyroidotomy.

Front 8

Overall Airway Ax

Back 8

I would perform my usual preop airway Ax, and in addition assess - neck size, anatomy, submandibular compliance, and lower airway (ie, SVC obstruction, etc). I would be assessing for difficulty with BMV, direct laryngoscopy, and potential for surgical airway.

I would do this via Hx / Ex / Ix.

Hx - anaesthetic charts, difficult airway letter, dental damage, OSA, positional dyspnoea, voice change, etc.

Ex - MP score, TMD, neck movement/anatomy, mandibular protrusion, neck circumference, mass, airway deviation, resp distress, stridor, sitting upright, pemberton's sign

Ix - CT-scan, C-spine xray, nasendoscopy, flow-volunme loops (spirometry).

Front 9

STOP - BANG score for OSA

Back 9

S - Snoring (loudly)

T - Tired during day

O - Obstruction = Apnoea witnessed

P - Pressure = High = >140/90

B - BMI > 35

A - Age > 50

N - Neck circumference > 40cm

G - Gender = Male


3/8 = high likelihood of OSA
6/8 = high likelihood of severe OSA
Polysomnography = AHI

Front 10

Sleep studies

Back 10

Polysomnography
- EEG, Oral/Nasal Airflow, Resp effort, Pulse oximetry, ECG, Electrooculagram
- apnoeas can be central or obstructive (resp effort or not)

Apnoea = cessation of airflow for > 10 secs or associated with desaturation > 4% drop
Hypopnoea = airflow <50% for > 10 secs

AHI
< 5 = Normal
5-15 = Mild OSA
15-30 = Mod OSA
>30 = Severe OSA
(Although varies acc to labs)


Overnight Oximetry
- Sats < 90%
- Overnight Desaturation Index - per hour

>10, >93% sensitivity for OSA. Good positive predictor.

Front 11

Extubation Criteria

Back 11

General
- Awake
- analgesed
- Warm
- Reversed
- HD stable

Respiratory
- VC>10-15ml/kg
- TV > 5ml/kg
- RR<25-30
- paO2 of 100 on fiO2 40% (p/f ratio of > 200)