Author Question: The therapist is about to initiate mechanical ventilation using heliox as the source gas. Which of ... (Read 42 times)

jilianpiloj

  • Hero Member
  • *****
  • Posts: 521
The therapist is about to initiate mechanical ventilation using heliox as the source gas. Which of the following considerations should the therapist take into account while setting the mechanical ventilator?
 
  A. to use volume ventilation
  B. to employ pressure ventilation
  C. to administer continuous mandatory ventilation with the patient sedated and paralyzed
  D. to avoid using any closed-loop modes of mechanical ventilation

Question 2

The therapist is using a Servo ventilator to ventilate a patient with heliox. How should the therapist anticipate the flow sensors on this ventilator to be affected by heliox?
 
  A. Because the flow sensors operate on the principle of thermal conductivity, they will be affected by heliox.
  B. Because the flow sensors are influenced by viscosity, they will be less affected by heliox.
  C. They are affected by gas density and will read erroneously.
  D. They will sense the flow of heliox accurately.



zhanghao

  • Sr. Member
  • ****
  • Posts: 316
Answer to Question 1

ANS: B
A. Incorrect response: See explanation B.
B. Correct response: Heliox administration via mechanical ventilation can be problematic. Ventilators are designed to deliver a mixture of air and O2. The different density and viscosity of helium can affect the delivered Vt and the exhaled Vt. For some ventilators, no reliable Vt is delivered with heliox. For other ventilators, a Vt higher than desired may be delivered. This problem can be circumvented partially by selecting pressure ventilation rather than volume ventilation. Unlike flow sensors, pressure sensors are not affected by a different gas composition.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.

Answer to Question 2

ANS: B
A. Incorrect response: See explanation B.
B. Correct response: The effect of heliox on the ability of the ventilator to correctly monitor flow and Vt depends on the method that is used for this measurement. Monitoring devices that are density dependent are inaccurate in the presence of heliox. Devices that use the principle of thermal conductivity are also affected. However, devices that are influenced by gas viscosity rather than by gas density are affected to a lesser degree because the viscosity of helium is only slightly different from that of air or O2. Screen pneumotachometers such as those used in the Servo ventilators are affected by viscosity rather than density. Thus, the flow sensors in these ventilators are affected to a lesser degree than occurs in other ventilators.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Pregnant women usually experience a heightened sense of smell beginning late in the first trimester. Some experts call this the body's way of protecting a pregnant woman from foods that are unsafe for the fetus.

Did you know?

Hyperthyroidism leads to an increased rate of metabolism and affects about 1% of women but only 0.1% of men. For most people, this increased metabolic rate causes the thyroid gland to become enlarged (known as a goiter).

Did you know?

Long-term mental and physical effects from substance abuse include: paranoia, psychosis, immune deficiencies, and organ damage.

Did you know?

There used to be a metric calendar, as well as metric clocks. The metric calendar, or "French Republican Calendar" divided the year into 12 months, but each month was divided into three 10-day weeks. Each day had 10 decimal hours. Each hour had 100 decimal minutes. Due to lack of popularity, the metric clocks and calendars were ended in 1795, three years after they had been first marketed.

Did you know?

It is important to read food labels and choose foods with low cholesterol and saturated trans fat. You should limit saturated fat to no higher than 6% of daily calories.

For a complete list of videos, visit our video library