Laryngology Seminar
Flexible Fibreoptic Intubation (FFI)- an alternative way of emergent
airway management
R3 蘇旺裕 2002/03/13
1967 Dr. Peter Murphy, 1st fibreoptic-guided tracheal intubation in anaesthetized pt
Introduction (Training needs manual dexterity & hand-eye coordination)
Difficult airway: conventionally trained anaesthesiologist experience difficulty with
mask ventilation, difficulty with tracheal intubation or both
Difficult laryngoscopy: (10%) impossible to see any of the vocal cords
(Cormack & Lehane, 1991)
Difficult endotracheal intubation: (1%) proper insertion of an endotracheal tube with
conventional laryngoscopy that requires more than 3 attempts, 10 min or both
Failed intubation: inability to place an endothracheal tube (0.05%)
Difficult mask ventilation: (0.01-0.03%) inadequate ventilation, maintain SaO2> 90%
(100% O2), positive pressure ventilation in pt with pre-op saturation>90%
Prediction (1)- Hx, PE
Risk: Obese, short neck, macroglossia, receding mandible (micrognathia), limited
mouth opening, structural anomaly, post R/T…
Prediction (2)- specific airway assessment
Patil distance <6cm (normal thyromental distance>6.5)
Savva distance <12cm (normal sternomental distance>12.5)
Mallampati classification, 1985 (Modified by Samsoon & Young, 1987)
1.anticipated difficult airway
pathological or anatomical factors
preserve natural airway
maintain spontaneous breathing
easier to intubate, less CV changes
can protect airway from aspiration of gastric contents
can monitor patient’s neurological status
2. anticipated difficult airway & awake intubation not feasible
uncooperative children/adults (learning difficulties, altered
cons level, language difficulties, bleeding…)
Awake FFI Procedure
Explanation & consent
Sedation (amnesia, analgesia)
Not complete numbness
No muscle relaxant
Monitoring
Continuous ECG, pulse oximetry, intermittent BP
Oxygenation
100% O2, hypopnea may last up to 2 min
if SaO2 drops below 90-95%→ mask ventilation
Premedication
Sedative & anxyolytics: relieve anxiety, produce amnesia (lorazepam, diazepam)
Opioids: mild sedatives, good analgesics, depress airway reflex, suppress cough
(morphine)
Prophylaxis of aspiration: cricoid pressure (Pimperan, H2-blocker)
Antisialogogues: dry mouth ensures cleaner field, better absorption & longer duration of
action of LA (atropine, Buscopan)
Conscious sedation
Benzodiazepine (Midazolam- quick onset, short duration; diazepam- slower, longer)
Opioids (morphine-no anxiolysis; fentanyl- quick onset, short duration)
Propofol (fast, easy to titrate, ! hypotension, !respiratory depression)
Upper airway local anaesthesia
Topical application of local anaesthesia (nasal, oral)- fast, easy
Inhalation of nebulized xylocaine- time-consuming
Nerve blocks (glossopharyngeal n., sup. laryngeal n.- supra- & infra- glottis)
Practical fibreoptic intubation techniques
Patient's position (supine, less usually sitting)
Operator's position (behind pt's head or stand besides)
Prepare local anesthesia (oral, nasal, upper airway)
Prepare for sedation, oxygenation
Check monitors, suction
Set up & check fibreoptic endoscopy equipments
Select route & tracheal tube
Perform endoscopy, advance tip over glottis
Railoading the tracheal tube (under direct vision)
Confirmation of tracheal tube position
Back-up plan if fails
Awake patient & cancel the operation
Transtracheal jet ventilation (TTJV)
Surgical airway (tracheostomy, cricothyrotomy)
Indications
Previous Hx of difficult intubation and/or mask ventilation
Anticipated difficult laryngoscopy on PE
Anticipated difficult mask ventilation
Risk of aspiration of gastric contents (trauma, emergency surgery & obstetrics)
Critical airway obstruction
haemodynamic stability desired
neurological assessment after intubation (unstable c-spine)
teaching, training & consolidation of experience
Contraindications
inexperience
patient refusal
local anaesthetic sensitivity
uncooperative adults
most children
Characteristics of FFI making it ideals intubating devices
Flexibility conforms easily to normal & difficult airway anatomy
Continuous visualization of airway during endoscopy
Less traumatic than rigid laryngoscope
Can be used with other intubating techniques (eg. direct laryngoscopy)
Can be used with ventilatory devices (eg. LMA)
Can be used on patients of all age groups
Can be used for oral or nasal intubation
Definitive check of tube position in trachea
Ability to use camera & monitor for teaching
Reference
1. Mansukh Popat. Practical Fibreoptic Intubation. Butterworth-Heinemann, 2001.
2. Williams K.N., Carli F., Cormack R.S. Unexpected difficult laryngoscopy: a
prospective survey in routine general surgery. Br J Anaes 1991; 66: 38-44.
3. Samson GLT, Young JRB. Difficult tracheal intubation: a retrospective study.
Anaesthesia 1987; 42: 487-90.
4. Benumof JL. ASA Difficult airway algorithm: new thoughts and considerations. In:
Hagberg CA ed. Handbook of Difficult Airway Management, pp 31-48. Churchill
Livingstone, Philadelphia, 2000.
5. Mallampati SR, GattSP, Gugino LD et al. A clinical sign to predict difficult
tracheal intubation: a prospective study. Can Anaesth Soc J 1985; 32: 429-34.
6. Mason RA. Learning fiberoptic intubation: fundamental problems. Anaesthesia
1992; 47: 729-31.
7. Rade B. Vukmir. Airway Management in the Critically Ill. 2001.
unanticipated difficult laryngoscopy during routine induction- can’t intubate, can
ventilate (recognized only after induction of anaesthesia)
unanticipated difficult intubation during rapid sequence induction
unanticipated difficult airway- can’t intubate & ventilate