Questions with Verified Answers
Graded A+
1. Choice of SGA vs ETT Answer: From UCSF site
My personal (positive) indication checklist for using an SGA includes the following items Answer:
-My patient does not have a significant aspiration risk
-My patient has a body mass that will allow me to use IPPV or PS if needed and achieve good tidal
volumes without high airway pressures
-I can access the airway during surgery
-If I had to convert from SGA to ETT during surgery I could easily do so
laryngeal mask provides better haemodynamic stability at induction and during emergence compared
with intubation and extubation. In addition, coughing is reduced during emergence with the classic
design laryngeal mask. Anesthetic requirements for 'tolerating' the laryngeal mask are lower than for
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,an ET tube, while oxygen saturation during emergence is higher. The incidence of a sore throat post-
operatively is reduced with the classic laryngeal mask design. SGAs are also easier to insert and are
placed blindly requiring a comparatively low skillset, as opposed to endotracheal tubes which need at the
very least a laryngoscope for placement and require more expertise to insert. The incidence of
laryngospasm during emergence is also lower with SGAs (Yu et al, 2010).
On the other hand, SGAs have some major downsides compared to intubation with an endotracheal tube
Answer:
First and foremost, SGAs do not protect the lungs from aspiration as a cutted endotracheal tube does.
Even though second generation devices otter improved aspiration protection (read 'Supraglottic airways
(SGAs)' on how they do that) compared to first generation devices, they do not otter the protection of
an endotracheal tube.
Secondly, the cutt seal pressure achieved with an SGA is limited compared to that of an ET tube.
Again, second generation devices fare better, often providing a seal up to 30- 35 cmH2O airway
pressure. The cutt seal of an endotra
2. Contraindictions to Cricoid Pressure (Sellick's Manuever) Answer:
Although considered a rare event, Sellick indicates that cricoid pressure may be detrimental in
the context of ongoing vomiting with concern for esophageal rupture as the vomitus dilates the
esophagus against a closed cricopharyngeus.
A relative contraindication is a cervical injury as posteriorly directed pressure may act as an exacerbating
factor.
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,It is recommended that cricoid pressure is released if there is a poor laryngeal view during the insertion
of a supraglottic airway device.
3. Correct Sizing of LMA Answer: From ASAHQ.com Answer:
We developed an easy single formula to determine LMA size based on patient weight as follows Answer:
LMA size is greater than or equal to Answer:
The square root of (the patient weight in kg / 5)
With this formula, it is easy to calculate a suitable LMA size for a patient of known weight. In addition,
there is
little ditterence between the calculated LMA size-patient weight relation between this formula and the
recommended formula.
For example, if the patient weighs 15 kg, the calculation would be as follows Answer: LMA size
e(15/5)0.5= (3)0.5= 1.7. In this case, a No. 2 LMA would be used.
Although some suggest that adult sizes of LMA (No. 4 and No. 5) can be selected based on sex, this
formula may also be applicable to these adult sizes. This formula is easy to remember and, we hope,
helpful in clinical situations.
4. Difficult Airway Algorithm Answer: DISCUSS AS A GROUP
general
5. Endobronchial Intubation Effects Answer: Undetected
anesthesia
endobronchial intubation during can cause serious complications such as
hypoxia, atelectasis and pneumothorax.
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, 6. Head Movement ETT Position Answer: From Head rotation, flexion, and extension
alter endotracheal tube position in adults and children. (2009)
In all patients, flexing the head resulted in the ETT moving towards the carina, and extension resulted in
the tube being displaced in the opposite direction. In adults, head rotation to the right resulted in
withdrawal of the ETT in all but one patient; displacement was 0.8 ± 0.5 cm (mean ± SD) (P < 0.001).
Head rotation to the left resulted in the endotracheal tube being displaced in an unpredictable direction
by 0.1 ± 0.6 cm. In children, head rotation to the right or left resulted in withdrawal of the ETT.
7. Head Position for Tracheal Intubation Answer: Sniflng Position
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