Exam 45: Mechanical Ventilators

A patient is receiving continuous mandatory ventilation through a constant flow generator in the control mode at a rate of 20/min with a V_T of 750 ml. The inspiratory time is 1 sec. What is the flow?

Which of the following is false about the application of flow triggering on a mechanical ventilator?

When you adjust the pressure drop necessary to trigger a breath on a ventilator, what are you adjusting on the machine?

What is the mode of ventilatory support in which patient's inspiratory efforts are augmented with a set amount of positive airway pressure?

Which of the following ventilator control systems are considered closed loop? 1) Orientation based 2) Servo 3) Adaptive 4) Optimal

A volume-cycled ventilator provides gas under positive pressure during inspiration until what point?

During volume control ventilation, the clinician has control over which of the following? 1) Pressure waveform 2) Volume waveform 3) Flow waveform

A patient is receiving continuous mandatory ventilation in the control mode at a rate of 10/min. The inspiratory time control is set at 40%. What is the inspiratory time?

While observing a patient receiving ventilatory support, you notice that all delivered breaths are initiated or terminated by the machine. Which of the following modes of ventilatory support is in force?

In which of the following situations is volume-controlled ventilation sometimes used? 1) When a precise PaCO₂ has to be maintained (some closed-head injuries) 2) When more even distribution of ventilation is required 3) When ventilating patients with severe, refractory hypoxemia 4) When ventilating patients with unstable or changing ventilatory drives

Which of the following are true of the relationship between flow and volume? 1) Volume is the integral of flow. 2) Volume is the derivative of flow. 3) Flow is the derivative of volume.

A mode that allows spontaneously breathing patients to breathe at a positive-pressure level, but drops briefly to a reduced pressure level for CO₂ elimination during each breathing cycle is also known as:

During mechanical ventilation, what variable causes a breath to begin?

To describe what happens during the expiratory phase of mechanical ventilation, you must know the value of which variable?

For which of the following uses might you consider the use of a purely pneumatically powered ventilator? 1) As a backup to electrically powered ventilators 2) When electrical device cannot be used (e.g., magnetic resonance imaging) 3) During certain types of patient transport

What ventilatory variable reaches and maintains a preset level before inspiration ends?

During volume-targeted ventilation, which of the following setting(s) determine(s) the total cycle time? 1) Volume 2) Flow 3) Rate

What is the application of pressure above atmospheric at the airway throughout expiration during mechanical ventilation?

During volume-targeted ventilation, which of the following settings determine the expiratory time? 1) Volume 2) Flow 3) Rate

Compared to using pressure as the trigger variable, what is the major advantage of flow-triggering?