Question 1

Which of the following indirect insults can cause ARDS?&#10;A) Pneumonia&#10;B) Chest trauma&#10;C) Closed head injury&#10;D) Cor pulmonale

Accepted Answer

ARDS can be caused by numerous insults (risk factors) that both directly and indirectly affect the lung via the generation of inflammatory mediators. Direct pulmonary insults include pneumonia, aspiration, chest trauma, and smoke inhalation. Indirect lung injury may be the result of generalized systemic conditions, such as sepsis, closed head injury, multiple trauma, transfusion reactions, and hemorrhagic shock.

Question 2

What acid-base abnormality does a patient generally display when experiencing stage 2 of ARDS?&#10;A) Mixed acidosis&#10;B) Respiratory alkalosis&#10;C) Respiratory acidosis&#10;D) Metabolic acidosis

Accepted Answer

The second stage, or latent period, lasts a variable period after the onset of acute injury. During this time the patient may appear clinically stable but begins to develop early signs of pulmonary injury or insufficiency manifested by hyperventilation with hypocarbia and respiratory alkalosis.

Question 3

Which of the following clinical signs characterizes the onset of the third stage of ARDS?&#10;A) Refractory hypoxemia&#10;B) Hypocarbia&#10;C) Increased anatomic dead space&#10;D) Decreased cardiac output

Accepted Answer

The third stage, acute respiratory failure, is heralded by the rapid onset of respiratory failure with hypoxemia refractory to supplemental oxygen. Diffuse pulmonary edema and worsening compliance cause significant atelectasis and intrapulmonary shunting.

Question 4

On the basis of the Berlin definition of Acute Respiratory Distress Syndrome (ARDS), the definition of moderate acute respiratory distress syndrome comprises which of the following components?
I. PaO₂/FiO₂ $\le$ 300 mm Hg
II. Onset of respiratory symptoms within 1 week of clinical insult
III. Pulmonary capillary wedge pressure greater than 18 mm Hg
IV. Chest imaging findings of new infiltrate consistent with acute pulmonary parenchymal disease

A) I and II only
B) I and III only
C) II and IV only
D) I, II, and IV only

Accepted Answer

Within 1 week of known clinical insult or new/worsening respiratory symptoms; bilateral opacities that are not fully explained by effusions, lobar/lung collapse, or nodules. Can be either on CXR or CT scan; with PEEP $\ge$5, mild ARDS: PaO₂/FiO₂ 201 to 300, moderate ARDS: PaO₂/FiO₂ $\le$ 200, severe ARDS: PaO₂/FiO₂ $\le$ 100; risk factors for ARDS must be present. Respiratory failure that is not fully explained by cardiac failure or fluid overload. If no risk factors are present, objective assessment (e.g., echocardiography) is required to exclude hydrostatic edema.

Question 5

How should the therapist use the point on the pressure-volume loop where the shape changes from concave to exponential? A) To set PEEP B) To set V_T C) To set Ti D) To set PIP

Accepted Answer

The point on the pressure-volume loop where the shape changes from concave to exponential is known as the lower inflection point. It reflects the pressure point at which alveoli begin to open and is located above functional residual capacity (see Figure 29-2 in the textbook). This suggests that many gas exchange units will collapse at normal transpulmonary pressures in acutely injured lungs and may need significant PEEP to maintain patency during expiration.

Question 6

Which of the following regions of the lungs is most likely to be unaffected by pathophysiology associated with ARDS?&#10;A) The dependent regions of the lung&#10;B) The nondependent regions of the lung&#10;C) The middle zone of the lung&#10;D) Depends on the etiology

Accepted Answer

Lung injury and areas of involvement in ARDS are heterogeneous and not uniform through all lung units. Some areas of the lung, typically in the dependent regions, are grossly affected. Other regions of the lung, typically in the nondependent regions, may be relatively unaffected. This creates varying areas of compliance within the lung itself. Dependent regions are generally fluid filled, atelectatic, and noncompliant. Nondependent areas are relatively normal and, thus, at risk for overdistention (i.e., volutrauma) and/or barotrauma during mechanical ventilation.

Question 7

What level of FiO₂ should the therapist avoid using long term in patients with ARDS? A) 0.40 B) 0.50 C) 0.60 D) Any level above 0.30

Accepted Answer

Every patient with ARDS is hypoxemic by definition. Prolonged administration of high concentrations of oxygen can damage the lungs, owing to the formation of highly reactive oxygen free radicals. Human and animal studies suggest that a prolonged FiO₂ greater than 0.60 should be avoided to prevent oxygen-induced pulmonary damage.

Question 8

Which of the following pathophysiologic changes seen in ARDS is responsible for the decrease in available surface area for gas exchange?&#10;A) Hyperinflation of the lungs&#10;B) Decreased right ventricular cardiac output&#10;C) Pulmonary hypertension&#10;D) Obliteration of small precapillary vessels

Accepted Answer

Vascular changes occur throughout the later stages of ARDS with obliteration of small precapillary vessels and an increase in the medial thickness of intra-acinar pulmonary arteries. Overall, these changes markedly decrease the available surface area for gas exchange and result in intractable respiratory failure or chronic lung disease, potentially requiring prolonged ventilator support.

Question 9

During the implementation of permissive hypercapnia, which of the following concepts is the most critical to prevent complications of this strategy? A) The PaCO₂ should never reach 100 mm Hg. B) The pH should never remain below 7.20. C) The rate at which the CO₂ rises may be more important than the actual PaCO₂. D) The target PaCO₂ should be reached in 48 hours.

Accepted Answer

A logical consequence of low tidal volume ventilation is hypercapnia. Limiting the peak inspiratory pressure by reducing the tidal volume may decrease minute ventilation and result in hypercapnia. The exact degree of respiratory acidosis that can be safely tolerated remains controversial. However, most undesirable effects are reversible and minor with respiratory acidosis when pH is greater than approximately 7.20.

Question 10

Radiographically, what features are typically seen in ARDS?&#10;A) Horizontal ribs&#10;B) Bilateral consolidations&#10;C) Widespread infiltrates&#10;D) Pleural effusions

Accepted Answer

Subsequently, hypoxemia and widespread infiltrates on chest radiograph can occur. This sequence of events may be triggered by both pulmonary and nonpulmonary insults.

Question 11

The therapist is auscultating a 2-year-old patient with ARDS. Which of the following is a common auscultatory finding in ARDS?&#10;A) Wheezing&#10;B) Stridor&#10;C) Crackles&#10;D) Pleural rub

Accepted Answer

The answer of The therapist is auscultating a 2-year-old patient...

Question 12

Which of the following ventilatory strategies is appropriate when mechanically ventilating a patient with ARDS? A) PEEP less than 15 cm H₂O and tidal volume (VT) between 8 and 10 mL/kg B) Peak inspiratory pressure (PIP) less than 40 cm H₂O and Pplateau less than 30 cm H₂O C) VT less than 6 mL/kg and Pplateau less than 30 cm H₂O D) A high or low level of PEEP and a VT between 8 and 10 mL/kg

Accepted Answer

The answer of Which of the following ventilatory strategies is...

Question 13

The therapist was titrating PEEP levels to maintain an SaO₂ of 85% and found that 13 cm H₂O were required to achieve this goal. What should be the most important concern with this level of PEEP? A) Risk of pneumothorax B) Decreased cardiac output C) Auto-PEEP D) Overdistention

Accepted Answer

The answer of The therapist was titrating PEEP levels to...

Question 14

A therapist is evaluating the progress of a patient with ARDS. The arterial blood gas reveals a PaO₂ of 55 mm Hg and a PaCO₂ of 65 mm Hg. The PEEP is set at 12 cm H₂O, and the mean airway pressure is 18 on an FiO₂ of 0.60. What is the OI in this patient?

A) 20.7
B) 13.1
C) 1.31
D) 200

Accepted Answer

The answer of A therapist is evaluating the progress of...

Question 15

What pathophysiologic change accounts for the alteration of the hysteresis curve during ARDS?&#10;A) High transpulmonary pressures&#10;B) High transairway pressures&#10;C) Hyperinflated lungs&#10;D) Refractory hypoxemia

Accepted Answer

The answer of What pathophysiologic change accounts for the alteration...

Question 16

What are some of the physical signs of respiratory failure among children?
I) Head bobbing
II) Nasal flaring
III) Crying
IV) Grunting

A) I and II only
B) I, II, and IV only
C) I, III, and IV only
D) II, III, and IV only

Accepted Answer

The answer of What are some of the physical signs...

Question 17

Which of the following interventions should the therapist implement to decrease mortality in patients with ARDS?&#10;A) High PEEP&#10;B) Alveolar recruitment maneuvers&#10;C) Low tidal volume&#10;D) High respiratory rate

Accepted Answer

The answer of Which of the following interventions should the...

Question 18

What level of Pplateau should the therapist target to improve outcomes in patients with ARDS? A) 35 cm H₂O B) 32 cm H₂O C) 28 cm H₂O D) 25 cm H₂O

Accepted Answer

The answer of What level of Pplateau should the therapist...

Question 19

Which of the following pathophysiologic conditions contribute to the decreased pulmonary compliance associated with ARDS?&#10;A) Destruction of alveolar type II cells&#10;B) Inactivation of pulmonary surfactant&#10;C) Fluid accumulation in the pleural spaces&#10;D) Rapid removal of fluid by the pulmonary lymphatics

Accepted Answer

The answer of Which of the following pathophysiologic conditions contribute...

Deck 29: Acute Respiratory Distress Syndrome