Author Question: Which of the following factors affects the consumption of source gas (O2) during the operation of ... (Read 31 times)

saraeharris · **on:** Jul 16, 2018

Which of the following factors affects the consumption of source gas (O2) during the operation of mechanical ventilators that are pneumatically or fluidically controlled? I. PEEP II. pulmonary compliance III. set minute ventilation IV. Fio2

A. I only
B. IV only
C. II, III only
D. I, II, III, IV

Question 2

The therapist is involved with preparing a mechanically ventilated patient for transport from the ICU. Which of the following humidification mechanisms should the therapist recommend for this patient during transport, which is expected to last about 1 hour? I. pass-over humidifier II. heat-moisture exchanger III. wick humidifier IV. None is necessary.

A. II only
B. IV only
C. I, III only
D. I, II, III only

mceravolo · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: D
A. Incorrect response: See explanation D.
B. Incorrect response: See explanation D.
C. Incorrect response: See explanation D.
D. Correct response: Under ideal conditions, all gas leaving the O2 source is delivered to the patient. However, in pneumatically or fluidically controlled ventilators, these control circuits often consume gas to power inspiration and expiration. Gas consumption is defined as gas used by the ventilator for operating circuits or valves, which is exhausted into the atmosphere and not delivered to the patient.

Answer to Question 2

ANS: A
A. Correct response: Humidification of the patient's airway is often overlooked during transport. Part of the reason is the difficulty and impracticality of transporting the patient with a humidification system during transport. The logistics and dangers of transporting an electrically powered, position-dependent, water-filled device are exasperating. However, humidification must be provided because delivery of anhydrous medical gases to the tracheobronchial tree can cause tissue damage in less than 30 minutes. A passive humidification device (i.e., a heat-moisture exchanger (HME) or artificial nose) may be used. An HME collects the patient's own respired heat and moisture during expiration, and returns them to the patient's respiratory tract during the ensuing inspiration. HMEs are not as efficient as heated humidification systems, but are particularly suited for patient transport.
B. Incorrect response: See explanation A.
C. Incorrect response: See explanation A.
D. Incorrect response: See explanation A.