A pediatric patient intubated with a 3.5-mm endotracheal tube is ...

[erika]

A pediatric patient intubated with a 3.5-mm endotracheal tube is receiving pressure support ven-tilation. The respiratory therapist notes patient-ventilator asynchrony and a rapid deceleration of flow that prematurely ends inspiration.
 
  The most appropriate action to alleviate this is which of the following?
  a. Increase the PS level.
  b. Increase the rise time.
  c. Decrease the PS level.
  d. Increase the flow cycle.

Question 2

A preterm neonate is being supported with nasal SiPAP.
 
  The baseline CPAP level is set at 6 cm H2O, the high CPAP level at 10 cm H2O, the rate is 20 sigh breaths, and the FIO2 is 0.8. The baby's PaO2 on these settings has been steadily declining and is now 48 mm Hg. The physician and respiratory therapist decided to use nasal HFV before intubating and using mechanical ventilation. The initial settings for NHFV for this patient should include which of the following?
  a. MAP = 10 cm H2O; frequency = 8 Hz; FIO2 = 1.0
  b. MAP = 10 cm H2O; frequency = 10 Hz; FIO2 = 0.8
  c. MAP = 6 cm H2O; frequency = 8 Hz; FIO2 = 0.8
  d. MAP = 6 cm H2O; frequency = 10 Hz; FIO2 = 1.0

[bubulittle310@msn.cn]

Answer to Question 1

ANS: B
ET tubes smaller than 4.5 mm may provide excessive resistance during PS. This can cause pres-surization of the ventilator circuit before sufficient flow enters the patient's airway. The result is a rapid deceleration of flow, which may prematurely end the inspiratory phase (premature pres-sure support termination PPST). This phenomenon does not allow the augmentation of VT, and patient-ventilator asynchrony may result. When PPST is suspected, a slower rise time can be used, which may reduce or eliminate the problem.

Answer to Question 2

ANS: D
The initial mean airway pressure for nasal HFV is usually set to equal the previous level of CPAP, with a frequency of 10 Hz. Because the nasal SiPAP baseline level was set at 6 cm H2O, the NHFV should be set at that level. The only option with those two set parameters includes the FIO2 of 1.0, which should be titrated down when oxygenation improves.