Question 1

In adult patients, spontaneous tidal volumes should be at least what value if weaning is to be successful?

Accepted Answer

Spontaneous tidal volumes should be at least 300 mL for successful weaning.

Question 2

Which of the following is least likely to cause an increase in a patient's tidal volume?

Accepted Answer

Metabolic alkalosis is least likely to cause an increase in tidal volume as it typically does not stimulate the respiratory drive like metabolic acidosis or sepsis, which can increase breathing to compensate for acid-base imbalances. Severe neurologic injury can also affect respiratory centers, potentially altering tidal volume.

Question 3

Weaning failure during a spontaneous breathing trial may be predicted when the spontaneous respiratory rate is greater than:

Accepted Answer

D

Question 4

An important advantage of monitoring mechanical tidal volumes proximally is that:

Accepted Answer

Monitoring tidal volumes proximally eliminates the compressible volume factor of tubing circuits, providing a more accurate measurement of the actual volume delivered to the patient.

Question 5

The "stacking" of breaths, which often is seen in mechanically ventilated patients with severe airway obstruction, can be caused by:

Accepted Answer

Insufficient expiratory time can lead to "stacking" of breaths, as it does not allow enough time for the patient to fully exhale before the next breath is delivered, causing air trapping and increased lung volumes.

Question 6

Which of the following activities are included in respiratory monitoring?
1) Alarm setting
2) Pulmonary consults
3) Physical examinations
4) Measurements and calculations

Accepted Answer

Respiratory monitoring includes alarm setting to alert for abnormal respiratory parameters, physical examinations to assess respiratory function, and measurements and calculations to quantify respiratory metrics. Pulmonary consults are not typically part of monitoring but rather part of treatment or diagnosis.

Question 7

Volutrauma is most likely to develop in:

Accepted Answer

Volutrauma is most likely to develop in nondependent lung regions due to overdistension from mechanical ventilation, as these areas tend to receive more ventilation compared to dependent regions.

Question 8

Which of the following are likely to cause a decrease in a patient's tidal volume?
1) Pulmonary edema
2) Metabolic acidosis
3) Acute respiratory distress syndrome
4) The postoperative period after coronary artery bypass surgery

Accepted Answer

Pulmonary edema, acute respiratory distress syndrome, and the postoperative period after coronary artery bypass surgery can all impair lung function or mechanics, leading to decreased tidal volume.

Question 9

Which of the following ventilator changes will have to be made if the problem of "breath stacking" is to be resolved?

Accepted Answer

Increasing inspiratory flow allows more time for exhalation, reducing the risk of breath stacking by preventing incomplete exhalation before the next breath begins.

Question 10

Ventilatory measurements routinely monitored at the bedside include which of the following?
1) Airway pressures
2) Lung volumes and flows
3) Fractional gas concentrations
4) Oxygen consumption and carbon dioxide production

Accepted Answer

Airway pressures, lung volumes and flows, and fractional gas concentrations are routinely monitored at the bedside to assess a patient's ventilatory status. Oxygen consumption and carbon dioxide production are not typically monitored at the bedside.

Question 11

It is important to monitor lung volumes in ICU patients because changes in lung volumes reflect which of the following changes?
1) Changes in gas exchange in the lung.
2) Changes in the patient's clinical status.
3) A response to therapy and any problems that may arise.
4) They influence the selection of antibiotic therapy in the ICU.

Accepted Answer

Monitoring lung volumes in ICU patients can indicate changes in gas exchange, reflect the patient's clinical status, and show responses to therapy or problems, but they do not influence antibiotic selection.

Question 12

Patients who are ventilated with excessively large tidal volumes are at risk for:

Accepted Answer

Ventilating patients with excessively large tidal volumes can cause volutrauma, which is lung injury due to overdistension of the alveoli.

Question 13

In a sedated, mechanically ventilated patient, inspiratory tidal volumes are consistently larger than expiratory tidal volumes. If it is assumed that there is no leak in the circuit, which of the following provides the best explanation for this discrepancy?

Accepted Answer

The compressibility factor of the ventilator circuit can cause a discrepancy between inspiratory and expiratory tidal volumes, as some of the inspired volume is used to expand the circuit itself, leading to a larger measured inspiratory volume compared to expiratory volume.

Question 14

Which of the following statements about the tidal volume is true?

Accepted Answer

Tidal volume is the amount of air inhaled or exhaled during normal breathing and is composed of alveolar volume (air reaching the alveoli for gas exchange) and dead space volume (air that does not participate in gas exchange).

Question 15

If intubated and mechanically ventilated patients are given shallow tidal volumes without sighs, which of the following is most likely to occur?

Accepted Answer

Shallow tidal volumes without periodic deep breaths (sighs) can lead to atelectasis, which is the collapse of part or all of a lung, due to insufficient alveolar expansion.

Question 16

Which of the following conditions explains why lung damage persists after recovery from a severe protracted episode of acute respiratory distress syndrome (ARDS)?

Accepted Answer

Volutrauma refers to lung injury caused by overdistension of alveoli due to mechanical ventilation, which can lead to persistent lung damage even after recovery from ARDS.

Question 17

In healthy, spontaneously breathing patients, an occasional increase in tidal volume to three or four times the normal level, which normally occurs about six to ten times each hour, is the definition of a:

Accepted Answer

A sigh is an occasional deep breath that increases tidal volume significantly and occurs several times an hour in healthy individuals.

Question 18

It is important to monitor ventilatory parameters in addition to arterial blood gases because:

Accepted Answer

Changes in ventilatory parameters often occur before they are reflected in arterial blood gases, allowing for earlier detection and intervention.

Question 19

Which of the following changes can decrease "breath stacking" in a mechanically ventilated patient?
1) A decreased ventilator rate
2) An increased inspiratory flow
3) A decreased expiratory time
4) A decreased mechanical tidal volume

Accepted Answer

Decreasing the ventilator rate and mechanical tidal volume can help prevent breath stacking by allowing more time for exhalation and reducing the volume of air delivered. Increasing inspiratory flow can also help by shortening the inspiratory time, thus allowing more time for expiration.

Question 20

In mechanically ventilated patients, the addition of positive end-expiratory pressure (PEEP) to normal tidal volumes is associated with which of the following effects? 1) Decrease in intrapulmonary shunting 2) Increase in functional residual capacity 3) Increase in partial pressure of arterial oxygen (PaO₂) 4) Increase in residual volume

Accepted Answer

PEEP helps to keep alveoli open, reducing intrapulmonary shunting, increasing functional residual capacity, and improving oxygenation, thus increasing PaO2.

Quiz 14: Respiratory Monitoring in the Intensive Care Unit