Question 1

Indications for delivering sigh breaths during mechanical ventilation include which of the following? 1) Before and after suctioning 2) During chest physical therapy 3) In patients with stiff lungs 4) When small V_T values are used

Accepted Answer

Sigh breaths during mechanical ventilation can be beneficial in various situations, including before and after suctioning to help re-expand collapsed alveoli, during chest physical therapy to enhance mucus clearance, and when small tidal volumes are used to prevent atelectasis and improve oxygenation.

Question 2

A chronic obstructive pulmonary disease (COPD) patient in respiratory failure is receiving ventilatory support in the volume-targeted intermittent mandatory ventilation mode at a rate of 6/min. You measure an auto-PEEP level of 9 cm H₂O. Which of the following would you recommend to decrease the effects of auto-PEEP in this patient?

Accepted Answer

Box 48-11 summarizes methods for minimizing the effects of auto-PEEP.

Question 3

When setting the tidal volume on a patient being mechanically ventilated, what criteria should be kept in mind?

Accepted Answer

Tidal volume usually is based on specific patient considerations but should ideally never result in a plateau pressure of 28 cm H₂O or greater.

Question 4

If available, the FiO₂ alarm should be set to what percentage?

Accepted Answer

Suggested initial settings for these alarms and backup ventilator settings are described in Table 48-5.

Question 5

A patient suffering from postoperative complications has been receiving mechanical ventilation for 6 days with a volume ventilator. A heat-moisture exchanger (HME) is providing control over humidification and airway temperature. Over the past 24 hr, the patient's secretions have decreased in quantity but are thicker and more purulent. Which of the following actions would you suggest at this time?

Accepted Answer

We prefer an optimal humidity approach and use of a heated humidifier to deliver gas in the range of 35° to 37° C at the airway.

Question 6

You have just placed a chronic obstructive pulmonary disease (COPD) patient on intermittent mandatory ventilation at a rate of 8/min, a V_T of 550 ml, and an FiO₂ of 0.40. To ensure proper equilibration between the alveolar and arterial gas tensions, how long should you wait before drawing a sample for measurement of the ABG?

Accepted Answer

ABGs should be measured 20 to 30 min after initiation of mechanical ventilation.

Question 7

After placing a patient on a volume-cycled ventilator in the continuous mandatory ventilation assist-control mode, you note that 55 cm H₂O pressure is required to deliver the preset V_T of 950 ml. What high-pressure limit would you now set for this patient?

Accepted Answer

If the plateau pressure is less than 30 cm H₂O, the high pressure limit can be adjusted to 10 to 20 cm H₂O above the peak inspiratory pressure.

Question 8

When adjusting a patient's oxygenation during mechanical ventilatory support, what should your goal be?

Accepted Answer

The FiO₂ is then titrated to achieve a PaO₂ in the range of 60 to 80 mm Hg with an SaO₂of 90% or greater or an SpO₂ of 92% or greater.

Question 9

Which of the following criteria should be met before considering use of a heat-moisture exchanger (HME) for a patient being placed on ventilatory support?
1) There should be no problem with retained secretions.
2) The patient should not have fever (normothermic).
3) The patient should be adequately hydrated.
4) The support should be short term (24 to 48 hr).

Accepted Answer

Heat-moisture exchangers (HMEs) are used for patients on ventilatory support to condition inspired air. They are most effective when the patient does not have issues with retained secretions, is normothermic (without fever), and is adequately hydrated. Although not strictly limited to short-term use, they are often considered for shorter durations of support. Therefore, all listed criteria are relevant for considering the use of an HME.

Question 10

What limits should be initially set for high and low V_T values and/or minute volume alarms on a ventilatory support device?

Accepted Answer

Suggested initial settings for these alarms and backup ventilator settings are described in Table 48-5.

Question 11

When the therapist is initially setting the high-pressure alarm on the ventilator and the patient's plateau pressure is less than 30 cm H₂O, what should the high-pressure alarm be set at?

Accepted Answer

If the plateau pressure is less than 30 cm H₂O, the high pressure limit can be adjusted to 10 to 20 cm H₂O above the peak inspiratory pressure.

Question 12

When using a heated humidifier during mechanical ventilation, the inspired gas temperature at the airway should be set to what level?

Accepted Answer

We prefer an optimal humidity approach and use of a heated humidifier to deliver gas in the range of 35° to 37° C at the airway.

Question 13

For which of the following patients requiring ventilatory support would you recommend against using a heat-moisture exchanger (HME) for airway humidification? 1) Patient with an expired V_Tless than 70% of the delivered V_T 2) Patient with a spontaneous minute ventilation of 14 L/min 3) Patient with body temperature less than 32° C

Accepted Answer

Heat-moisture exchangers (HMEs) are contraindicated or not recommended for patients with expired tidal volumes less than 70% of the delivered tidal volume, those with high spontaneous minute ventilation (e.g., >10 L/min), and patients with hypothermia (body temperature less than 32° C), as these conditions can impair the HME's effectiveness or exacerbate the patient's condition.

Question 14

What is the predicted change in tidal volume by adding 6 in of tubing to a ventilator circuit?

Accepted Answer

In general, V_T reduces between 50 and 70 ml for each 6 in (15 cm) of dead space added by tubing in a circuit.

Question 15

Which of the following would you initially verify in assessing the airway of a patient placed on ventilatory support?
1) Cuff pressure
2) Tube position
3) Tube patency

Accepted Answer

When assessing the airway of a patient placed on ventilatory support, it is important to verify all three options: cuff pressure to ensure it is appropriate and not causing damage to the trachea or allowing air leaks, tube position to ensure it is not in the esophagus or causing trauma or dislodgement, and tube patency to ensure there is no blockage preventing air flow. Thus, option B) of verifying all three is the best choice.

Question 16

A heat-moisture exchanger (HME) should be avoided in which of the following circumstances? 1) Patients with excessive secretions 2) Patients with a high FiO₂ 3) Patients with low body temperature

Accepted Answer

The answer of A heat-moisture exchanger (HME) should be avoided...

Question 17

A dehydrated, feverish patient suffering from acute bacterial pneumonia is being intubated in order to provide mechanical ventilatory support. Which of the following devices would you select to control humidification and airway temperature for this patient?

Accepted Answer

We prefer an optimal humidity approach and use of a heated humidifier to deliver gas in the range of 35° to 37° C at the airway.

Question 18

After setting up a patient on a ventilatory support device, which of the following supplementary equipment would you require to be available at the bedside? 1) Suction source and catheters 2) Backup artificial airway 3) Manual resuscitator with O₂

Accepted Answer

When setting up a patient on a ventilatory support device, it is essential to have a suction source and catheters for airway clearance, a backup artificial airway in case of dislodgement or malfunction, and a manual resuscitator for emergency ventilation if the device fails or during patient transfer.

Question 19

Which of the following would you assess immediately after a patient is placed on a ventilatory support device?
1) ABGs
2) Patient's airway
3) Patient's vital signs

Accepted Answer

After a patient is placed on a ventilatory support device, it is crucial to immediately assess the patient's airway to ensure it is secure and clear, their vital signs to monitor for any immediate changes or complications, and arterial blood gases (ABGs) to evaluate the effectiveness of the ventilation and oxygenation.

Question 20

When titrating the FiO₂ level downward from 100% to 40%, what is the maximum increment that should be applied between estimates of oxygenation?

Accepted Answer

In either case, it is suggested that O₂ levels be titrated down from 100% to 50% O₂ in decrements not to exceed 20%.

Quiz 48: Initiating and Adjusting Invasive Ventilatory Support

Indications for delivering sigh breaths during mechanical ventilation include which of the following? 1) Before and after suctioning 2) During chest physical therapy 3) In patients with stiff lungs 4) When small VT values are used

When setting the tidal volume on a patient being mechanically ventilated, what criteria should be kept in mind?

If available, the FiO2 alarm should be set to what percentage?

After placing a patient on a volume-cycled ventilator in the continuous mandatory ventilation assist-control mode, you note that 55 cm H2O pressure is required to deliver the preset VT of 950 ml. What high-pressure limit would you now set for this patient?

When adjusting a patient's oxygenation during mechanical ventilatory support, what should your goal be?

What limits should be initially set for high and low VT values and/or minute volume alarms on a ventilatory support device?

When the therapist is initially setting the high-pressure alarm on the ventilator and the patient's plateau pressure is less than 30 cm H2O, what should the high-pressure alarm be set at?

When using a heated humidifier during mechanical ventilation, the inspired gas temperature at the airway should be set to what level?

What is the predicted change in tidal volume by adding 6 in of tubing to a ventilator circuit?

Which of the following would you initially verify in assessing the airway of a patient placed on ventilatory support? 1) Cuff pressure 2) Tube position 3) Tube patency

A heat-moisture exchanger (HME) should be avoided in which of the following circumstances? 1) Patients with excessive secretions 2) Patients with a high FiO2 3) Patients with low body temperature

A dehydrated, feverish patient suffering from acute bacterial pneumonia is being intubated in order to provide mechanical ventilatory support. Which of the following devices would you select to control humidification and airway temperature for this patient?

After setting up a patient on a ventilatory support device, which of the following supplementary equipment would you require to be available at the bedside? 1) Suction source and catheters 2) Backup artificial airway 3) Manual resuscitator with O2

Which of the following would you assess immediately after a patient is placed on a ventilatory support device? 1) ABGs 2) Patient's airway 3) Patient's vital signs

When titrating the FiO2 level downward from 100% to 40%, what is the maximum increment that should be applied between estimates of oxygenation?

Indications for delivering sigh breaths during mechanical ventilation include which of the following? 1) Before and after suctioning 2) During chest physical therapy 3) In patients with stiff lungs 4) When small V_T values are used

If available, the FiO₂ alarm should be set to what percentage?

After placing a patient on a volume-cycled ventilator in the continuous mandatory ventilation assist-control mode, you note that 55 cm H₂O pressure is required to deliver the preset V_T of 950 ml. What high-pressure limit would you now set for this patient?

What limits should be initially set for high and low V_T values and/or minute volume alarms on a ventilatory support device?

When the therapist is initially setting the high-pressure alarm on the ventilator and the patient's plateau pressure is less than 30 cm H₂O, what should the high-pressure alarm be set at?

A heat-moisture exchanger (HME) should be avoided in which of the following circumstances? 1) Patients with excessive secretions 2) Patients with a high FiO₂ 3) Patients with low body temperature

After setting up a patient on a ventilatory support device, which of the following supplementary equipment would you require to be available at the bedside? 1) Suction source and catheters 2) Backup artificial airway 3) Manual resuscitator with O₂

When titrating the FiO₂ level downward from 100% to 40%, what is the maximum increment that should be applied between estimates of oxygenation?