A morbidly obese male with an unstable cervical fracture and a history of a difficult intubation
(Mallampati class IV airway with mouth opening <15 mm) is scheduled for a C3-4 cervical fusion. Which
intubation technique with in-line stabilization is MOST appropriate?
Asleep direct laryngoscopy
Awake fiberoptic bronchoscopy
Asleep fiberoptic bronchoscopy
Awake video laryngoscopy - Answers Awake fiberoptic bronchoscopy
Justification
An awake fiberoptic bronchoscope intubation is the most appropriate airway management technique in
a patient with a history of a difficult intubation and 3 predictors of a difficult airway (morbid obesity,
Mallampati class IV, and mouth opening <15 mm). Additionally, this technique will cause the least
cervical spine motion and will allow the patient to maintain spontaneous ventilation. Morbidly obese
patients may be difficult to mask ventilate and can desaturate quickly after induction of anesthesia,
indicating that induction of anesthesia may be most appropriate after the airway is secured. A possible
contraindication to video laryngoscopy intubation is a mouth opening <15 mm.
Airway management with a supraglottic airway is CONTRAINDICATED in a patient with:
symptomatic hiatal hernia.
asthma.
coronary artery disease.
,hypothyroidism. - Answers symptomatic hiatal hernia.
Justification
Supraglottic airways are contraindicated when the patient is at high risk for aspiration of gastric
secretions. A patient with a symptomatic hiatal hernia is at high risk for aspiration of gastric secretions.
An E-cylinder of oxygen with a service pressure of 1,900 PSI contains how many liters of oxygen?
1,590
190
660
330 - Answers 660
Justification
A filled E-cylinder of oxygen has a service pressure of 1,900 PSI and contains 660 L of oxygen. An E-
cylinder that is half empty (service pressure of 950 PSI) would contain half that volume, or 330 L of
oxygen.
Which neuromuscular monitoring technique is appropriate for the evaluation of time to recovery from a
deep blockade with rocuronium (Zemuron)?
Double-burst stimulation
Posttetanic count stimulation
Tetanic stimulation
,Train-of-four stimulation - Answers Posttetanic count stimulation
Justification
Deep blockade secondary to nondepolarizing neuromuscular blocking agents is characterized by no
twitch response in a train-of-four (0/4), but with the presence of a posttetanic count =1 twitch.
Posttetanic count stimulation is useful in helping to estimate the amount of time until reappearance of a
train-of-four response (=1/4 twitches). Because there is no response to train-of-four and single-twitch
stimulation under the condition of deep neuromuscular blockade, these modes of stimulation cannot be
used to determine the degree of block. The time until return of the first response to train-of-four
stimulation is related to the number of posttetanic twitch responses present.
What is responsible for an abrupt decrease in end-tidal carbon dioxide (ETCO2) to near zero with the
absence of an ETCO2 waveform?
Malfunction of unidirectional inspiratory valve
Exhausted carbon dioxide absorbent material
Loss of suction on the scavenge system
Anesthesia circuit disconnection - Answers Anesthesia circuit disconnection
Justification
The sudden decrease in ETCO2 and absence of an ETCO2 waveform would occur with an anesthesia
circuit disconnect, discontinuing the sampling of expired carbon dioxide. The malfunction of the
unidirectional inspiratory valve and exhausted carbon dioxide absorbent material would result in an
increase in ETCO2 (increasing ETCO2 waveform).
Which muscle relaxant is MOST appropriate in patients with advanced liver disease?
, Rocuronium (Zemuron)
Pancuronium (Pavulon)
Cisatracurium (Nimbex)
Vecuronium (Norcuron) - Answers Cisatracurium (Nimbex)
Justification
Cisatracurium is metabolized by Hofmann elimination. All other choices have some degree of liver
metabolism
During administration of anesthesia to a patient with sickle cell disease, which action minimizes sickling?
Restriction of fluids
Administration of 100% oxygen
Avoidance of hyperthermia
Continued hypoventilation - Answers Administration of 100% oxygen
Justification
Increased oxygen concentration limits the sickling process. The rest of the choices contribute to sickling.
Sickling is increased with lowered oxygen tensions, acidosis, low cardiac output with low-flow states,
and hypothermia. Current therapy includes prevention of hypothermia, providing hydration, controlling
ventilation to avoid acidosis, and giving supplemental oxygen.
Which valve on the anesthesia gas machine allows respiratory gas to flow to and from a patient?