NBRC Respiratory Therapist 2 — Questions and Answers
Question 1: A patient on mechanical ventilation develops sudden hypotension, tachycardia, and decreased breath sounds on the left. What is the most likely cause?
- Pulmonary embolism
- Tension pneumothorax (Correct answer)
- Atelectasis
- Mucus plug
Correct answer: Tension pneumothorax
Tension pneumothorax causes mediastinal shift, compressing the heart and great vessels, leading to hemodynamic instability.
Question 2: Which parameter best indicates a patient's readiness to wean from mechanical ventilation?
- PaO2 > 60 mmHg on FiO2 ≤ 0.40
- Rapid Shallow Breathing Index (RSBI) < 105 (Correct answer)
- Tidal volume > 5 mL/kg IBW
- PEEP ≤ 10 cmH2O
Correct answer: Rapid Shallow Breathing Index (RSBI) < 105
An RSBI (f/VT) < 105 breaths/min/L is the strongest single predictor of successful extubation.
Question 3: A patient with COPD presents with pH 7.30, PaCO2 58 mmHg, PaO2 52 mmHg, and HCO3 28 mEq/L. What is the correct interpretation?
- Acute respiratory alkalosis
- Metabolic acidosis with compensation
- Acute-on-chronic respiratory acidosis (Correct answer)
- Chronic respiratory acidosis fully compensated
Correct answer: Acute-on-chronic respiratory acidosis
Elevated HCO3 indicates chronic CO2 retention, but pH below 7.35 suggests an acute exacerbation superimposed on the chronic state.
Question 4: When performing nasotracheal suctioning, the maximum suction pressure for an adult should not exceed:
- -80 mmHg
- -120 mmHg (Correct answer)
- -150 mmHg
- -200 mmHg
Correct answer: -120 mmHg
Adult nasotracheal suctioning should not exceed -120 mmHg to avoid mucosal trauma and hypoxia.
Question 5: Which inhaled medication is classified as a long-acting muscarinic antagonist (LAMA)?
- Ipratropium bromide
- Tiotropium bromide (Correct answer)
- Albuterol sulfate
- Salmeterol xinafoate
Correct answer: Tiotropium bromide
Tiotropium is a LAMA with a 24-hour duration of action, used for maintenance therapy in COPD.
Question 6: A 70 kg adult patient receives volume-controlled ventilation at VT 500 mL, rate 14, PEEP 5. Peak pressure is 45 cmH2O and plateau pressure is 42 cmH2O. What is the primary problem?
- Decreased lung compliance (Correct answer)
- High airway resistance
- Auto-PEEP
- ETT obstruction
Correct answer: Decreased lung compliance
When plateau pressure is high and the peak-to-plateau gradient is small, the problem is low lung compliance, not airway resistance.
Question 7: Which oxygen delivery system is BEST suited for a patient who requires precise FiO2 control regardless of respiratory pattern?
- Simple face mask
- Non-rebreather mask
- Venturi mask (Correct answer)
- Nasal cannula at 4 L/min
Correct answer: Venturi mask
The Venturi mask uses fixed air-entrainment orifices to deliver accurate, predetermined FiO2 independent of patient flow.
NBRC Respiratory Therapist 2
A patient on mechanical ventilation develops sudden hypotension, tachycardia, and decreased breath sounds on the left.
What is the most likely cause?