| Difficult Airway Management
at the Department
of Anesthesiology |
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Fiberoptic
Intubation Movie SECTION 3 SECTION 4 |
The “Open it up, line it up” approach for
FIBEROPTIC INTUBATION
Watch the movie first! - Fiberoptic Intubation movie Six Essentials to Success
1Choose the appropriate fiberoptic intubation mode Anesthetized
Oral ■
Practice anesthetized oral fiberoptic intubations until you are completely
familiar with the equipment, setup and anatomy. Practice until you are
thoroughly versed in manipulating the fiberoptic shaft and airway. ■
Always establish effective mask ventilation and good oxygen saturation and
limit each attempt to one minute. ■ Try
to practice with a skilled practitioner, who can use a TV monitor to guide
you. Do not do oral fiberoptic
intubations on anesthetized patients in whom a rapid sequence intubation
is indicated, e.g., patients with a full stomach, potential for gastric
reflux and/or obesity. Anesthetized
Nasal Awake Oral You may consider using an awake
oral approach in Mallampati Grade III and IV patients (Figure A). With
these patients, the posterior pharyngeal wall is not visible and the
thyromental distance is less than 7 cm. Awake Nasal An awake nasal approach is indicated in patients undergoing an operation on the mouth and/or oral cavity. 2
Setup the fiberoptic scope. Place the bronchoscope and its cart on the left side of the patient. Why?
Because the cables insert on the left side of the bronchoscope handle when
the bronchoscope lever is on the under side (as it should be). Make sure
all cables are free of loops. ■ Turn the light source on high when
you start the intubation. ■ Optional—Flow oxygen
through the scope suction port to improve oxygenation and to displace
secretions. 3
3Prepare the
awake patient. Carefully
explain the intubation procedure to the patient. Administer supplemental
oxygen via nasal prongs. Give glycopyrrolate
(.2 –.3 mg IV) and sedate with 1–2 mg midazolam IV 30 minutes prior to
topical anesthesia.
Then before topical anesthesia, titrate fentanyl 50 to 250 mg
IV. Keep the patient responsive! Topical anesthesia:
Trans-oral trickle
Time the injection of each increment to coincide with inspiration. Pause
for a minute after the first 2 cc but continue to hold the tongue to
prevent swallowing. Total lidocaine
dose should not exceed 3–4 mg/kg.* Reduce the dose if the patient has
impaired liver function.
Transtracheal injection (not shown) An alternative approach,
especially for obese patients with excessive oral mucosa, is to use a
20-gauge plastic catheter and inject 4 cc of 2-4% lidocaine through the
cricothyroid ligament. Then, while the patient inhales, spray the
oropharynx with 4% lidocaine and allow 10 minutes for analgesia to take
effect. Superior laryngeal nerve blocks can be done at this time, but they
aren’t needed if there is a good transtracheal injection and pharyngeal
spray. Note: If the patient is awake prior to intubation, place a dental bite block between the teeth to one side (Figure). Remember, one bite of the scope shaft costs about $2,000.
Once on the operating room table, whether the patient is awake or to be anesthetized, elevate the head at least 8 cm. Lower the table as far as possible and/or stand on a lift. Your goal is to straighten the fiberoptic shaft and hence gain better control of the tip. 4Open
up the airway. While artificial airways are available to aid in exposing the cords, the tongue pull method, described here, does not require such an airway at all. I use the tongue pull for both oral and nasal approaches. n After
a couple of deep breaths (you and the patient), suction the pharynx
whether the patient is anesthetized or awake. n If the patient is anesthetized, apply the suction tube to the tip of the tongue. Drag the tongue upward (Figure).
n
Instruct your assistant to monitor oxygen saturation while you are doing
the intubation. Know where that tip points before it disappears from view!
n
Look at the shaft, not through the eye piece. Position the
shaft above the middle of the patient’s mouth or nose at 90 degrees to
the horizontal. n Flex the tip of the shaft maximally and position the shaft so that the flexed tip points precisely down the middle of the neck (Figure).
n
Now straighten
the tip. In an oral approach: without tilting or bending or
rotating the shaft even a tiny bit, insert the shaft exactly in the
midline of the mouth and oropharynx until the tip hits the rear of the
mouth (about 9 cm). In a nasal approach, insert the tip into the nose,
keeping the tip slightly flexed so that it follows the base of the nose
until you view the posterior nasal pharynx. n Now carefully bring the eyepiece down to your eye or look at the TV monitor. Then slowly flex the tip of the shaft so you see the epiglottis or glottis, or, in a nasal approach, until you see the "tunnel" consisting of the palate above and the posterior nasal pharynx below.
If you get
“lost,” withdraw the shaft completely and check the flexed tip
orientation. If you get “lost” again, advance in the midline toward
the darkest site, i.e. “head for the black.” n
Advance the tip under the epiglottis until the cords come into view. If
you find the tip off to one side of the glottis, rotate both shaft and
handle until the tip is over the glottis. n If
there is no open space between the epiglottis and posterior pharynx, have
your assistant let go of the tongue and left up on the mandible. If
you are midline, you’ll see the glottic opening. 6Advance
the shaft and tube.
n
Advance the
fiberoptic scope tip until you can just see the carina. If the patient is
awake, don’t advance the tip past mid-trachea because you may induce
coughing. n Use
your left hand to loosen the endotracheal tube connector from the
bronchoscope handle. n Now, grasp the endotracheal tube at its midpoint and rotate it 90 degrees counterclockwise so the Murphy eye is anterior. This maneuver prevents the tube tip from hanging up on the right arytenoid. Hang-up occurs because the fiberoptic shaft falls posteriorly into the interarytenoid fissure (Figure).
If
the tube still hangs up, rotate the tube another 90 degrees counterclockwise.
n
Advance the endotracheal tube into the trachea over the bronchoscope shaft
until the 22-cm or 23-cm mark on the tube is at the teeth. n
Withdraw the fiberoptic shaft and secure the endotracheal tube. epiglottis. To avoid this hang-up, rotate the tube 90 degrees clockwise as you advance it.
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