A 68-year-old, 5-foot, 10-inch male patient with acute-on-chronic ...

[nevelica]

A 68-year-old, 5-foot, 10-inch male patient with acute-on-chronic respiratory failure due to COPD has been placed on NIV with these settings: IPAP = 8 cm H2O, EPAP = 4 cm H2O, FIO2 = 0.28.
 
  The patient's measured exhaled volume is 350 mL with a spontaneous respiratory rate of 24 breaths/min. The resulting arterial blood gas values are: pH = 7.27, PaCO2 = 77 mm Hg, PaO2 = 64 mm Hg, SaO2 = 88, HCO3 = 36 mEq/L. What action should the respiratory therapist take at this time?
  a. Increase the FIO2 to 0.4.
  b. Increase the EPAP to 6 cm H2O.
  c. Increase the IPAP to 12 cm H2O.
  d. Decrease the EPAP to 2 cm H2O.

Question 2

All of the following patients are intubated and receiving mechanical ventilation. Which of them is most likely to require slow liberation from mechanical ventilation?
 
  a. A patient who overdosed on diazepam
  b. A postoperative patient who had knee surgery
  c. A patient with a severe exacerbation of asthma
  d. A patient with chest contusions from a motor vehicle crash

[nickk12214]

Answer to Question 1

ANS: C
This patient has an acute-on-chronic respiratory acidosis that has not been corrected by the NIV at the current settings. The resulting VT is 4.7 mL/kg, which is not enough to reduce the PaCO2 to an acceptable DIF for this patient (the pH should be about 7.37). Titrating the IPAP DIF to maintain an exhaled VT of 5-7 mL/kg can be accomplished by increasing the IPAP.

Answer to Question 2

ANS: D
A large percentage of patients who need temporary mechanical ventilation do not require a grad-ual withdrawal process. Such patients include those receiving postoperative ventilatory support for recovery from anesthesia, treatment of uncomplicated drug overdose, and exacerbation of asthma. The patient with chest contusions from an accident has a higher risk of developing prob-lems that will require a more gradual weaning process.