Author Question: What are some key causes of patient-ventilator asynchrony and increased work of breathing dur-ing ... (Read 46 times)

AEWBW · **on:** Jul 16, 2018

What are some key causes of patient-ventilator asynchrony and increased work of breathing dur-ing pressure-triggered volume-controlled continuous mandatory ventilation?

1. Improper trigger setting
2. Insufficient inspiratory flow
3. High peak airway pressures
a. 1 and 2 only
b. 1 and 3 only
c. 2 and 3 only
d. 1, 2, and 3

Question 2

Which of the following modes of ventilatory support would result in the highest mean airway pressure?

a. Volume-controlled intermittent mandatory ventilation
b. (Volume-controlled intermittent manda-tory ventilation) + pressure-supported ventilation
c. Pressure-controlled intermittent mandato-ry ventilation
d. Volume-controlled continuous mandatory ventilation

leahm14 · **Reply #1 on:** Jul 16, 2018

Answer to Question 1

ANS: A
If sensitivity is set too low, such that considerable effort is necessary to trigger the ventilator, pa-tient-ventilator asynchrony occurs. A pressure sensitivity of 0.5 to 1.5 cm H2O or flow sensi-tivity of 1 to 2 L/min is regarded as optimal. Inspiratory flow must be set to meet the patient's inspiratory demand. An insufficient inspiratory flow can cause patient-ventilator asynchrony and increased work of breathing.

Answer to Question 2

ANS: D
Because every breath is volume controlled, mean airway pressure tends to be greater compared with the mean airway pressure with synchronized intermittent mandatory ventilation and pres-sure-supported ventilation, and pulmonary arterial pressure and cardiac output may be lower.