RRT RRT Clinical Concepts 2 — Questions and Answers
Question 1: A patient with ARDS has a PaO2 of 55 mmHg on FiO2 0.80. The best next step is to:
- Increase FiO2 to 1.0
- Apply PEEP of 10 cmH2O (Correct answer)
- Switch to pressure control ventilation
- Administer inhaled nitric oxide
Correct answer: Apply PEEP of 10 cmH2O
Increasing PEEP recruits alveoli and improves oxygenation in ARDS more effectively than simply raising FiO2 beyond 0.80.
Question 2: Which ventilator parameter best reflects small airway resistance in a mechanically ventilated patient?
- Peak inspiratory pressure (Correct answer)
- Plateau pressure
- Mean airway pressure
- Auto-PEEP
Correct answer: Peak inspiratory pressure
Peak inspiratory pressure reflects both airway resistance and lung/chest wall compliance, making it the primary indicator of small airway resistance changes.
Question 3: A patient receiving mechanical ventilation develops sudden hypotension, decreased breath sounds on the left, and tracheal deviation to the right. The priority action is:
- Obtain a stat chest X-ray
- Perform needle decompression of the left chest (Correct answer)
- Increase PEEP
- Administer IV fluid bolus
Correct answer: Perform needle decompression of the left chest
These signs indicate tension pneumothorax, which requires immediate needle decompression before imaging.
Question 4: Which bronchodilator class works by inhibiting acetylcholine receptors to reduce bronchoconstriction?
- Beta-2 agonists
- Methylxanthines
- Anticholinergics (Correct answer)
- Leukotriene modifiers
Correct answer: Anticholinergics
Anticholinergics such as ipratropium block muscarinic receptors, preventing acetylcholine-mediated bronchoconstriction.
Question 5: A patient's arterial blood gas shows pH 7.25, PaCO2 60 mmHg, HCO3 25 mEq/L. This represents:
- Metabolic acidosis
- Respiratory alkalosis
- Acute respiratory acidosis (Correct answer)
- Compensated metabolic acidosis
Correct answer: Acute respiratory acidosis
The low pH with elevated PaCO2 and near-normal bicarbonate indicates acute respiratory acidosis without metabolic compensation.
Question 6: The primary goal of lung-protective ventilation in ARDS is to prevent:
- Oxygen toxicity
- Ventilator-induced lung injury (Correct answer)
- Pulmonary embolism
- Atelectasis
Correct answer: Ventilator-induced lung injury
Lung-protective ventilation uses low tidal volumes (4-6 mL/kg IBW) and limited plateau pressures to prevent ventilator-induced lung injury (VILI).
Question 7: During a spontaneous breathing trial, which finding would indicate the patient is NOT ready for extubation?
- Respiratory rate of 18/min
- SpO2 of 96% on 40% FiO2
- Rapid shallow breathing index (RSBI) of 120 (Correct answer)
- Tidal volume of 450 mL
Correct answer: Rapid shallow breathing index (RSBI) of 120
An RSBI greater than 105 predicts failure of extubation; an RSBI of 120 indicates the patient is breathing too rapidly and shallowly.
RRT RRT Clinical Concepts 2
A patient with ARDS has a PaO2 of 55 mmHg on FiO2 0.80.
The best next step is to: