RRT RRT 4 — Questions and Answers
Question 1: Which ventilator waveform pattern indicates air trapping (auto-PEEP) on a flow-time scalar?
- Inspiratory flow that never reaches zero
- Expiratory flow that does not return to zero before the next breath (Correct answer)
- A square wave inspiratory flow pattern
- Decreased peak inspiratory flow
Correct answer: Expiratory flow that does not return to zero before the next breath
Auto-PEEP is identified when expiratory flow fails to return to baseline (zero) before the next inspiratory cycle begins.
Question 2: Which of the following is a contraindication to non-invasive positive pressure ventilation (NIPPV)?
- COPD exacerbation with hypercapnia
- Cardiogenic pulmonary edema
- Inability to protect airway due to altered mental status (Correct answer)
- Hypoxemic respiratory failure from pneumonia
Correct answer: Inability to protect airway due to altered mental status
Patients unable to protect their airway due to decreased consciousness are at high risk for aspiration and should be intubated.
Question 3: What does a shift of the oxyhemoglobin dissociation curve to the RIGHT indicate?
- Increased hemoglobin affinity for oxygen
- Decreased release of oxygen to tissues
- Decreased hemoglobin affinity for oxygen and increased tissue oxygen delivery (Correct answer)
- Metabolic alkalosis
Correct answer: Decreased hemoglobin affinity for oxygen and increased tissue oxygen delivery
A rightward shift (Bohr effect) decreases hemoglobin-O2 affinity, promoting oxygen release to tissues; caused by acidosis, hyperthermia, or elevated 2,3-DPG.
Question 4: Which parameter best reflects the adequacy of alveolar ventilation?
- PaO2
- SaO2
- PaCO2 (Correct answer)
- SpO2
Correct answer: PaCO2
PaCO2 directly reflects CO2 elimination and is the gold-standard measure of alveolar ventilation adequacy.
Question 5: A patient on mechanical ventilation develops sudden decrease in SpO2, increased peak airway pressure, absent breath sounds on the left, and tracheal deviation to the right. The MOST likely diagnosis is:
- Right mainstem intubation
- Left-sided tension pneumothorax (Correct answer)
- Pulmonary embolism
- Mucus plug in left bronchus
Correct answer: Left-sided tension pneumothorax
Absent left breath sounds, tracheal deviation away from the affected side, and hemodynamic instability indicate left-sided tension pneumothorax requiring emergency needle decompression.
Question 6: Which inhaled medication is classified as an anticholinergic bronchodilator and is commonly used in COPD maintenance therapy?
- Fluticasone
- Albuterol
- Budesonide
- Tiotropium (Correct answer)
Correct answer: Tiotropium
Tiotropium is a long-acting muscarinic antagonist (LAMA) that blocks M3 receptors to produce sustained bronchodilation in COPD.
Question 7: The recommended tidal volume for lung-protective ventilation in ARDS is:
- 10-12 mL/kg ideal body weight
- 6-8 mL/kg ideal body weight (Correct answer)
- 8-10 mL/kg ideal body weight
- 4-5 mL/kg actual body weight
Correct answer: 6-8 mL/kg ideal body weight
ARDSNet protocol recommends 6 mL/kg IBW (with allowance to 8 mL/kg) to minimize ventilator-induced lung injury.
RRT RRT 4
Which ventilator waveform pattern indicates air trapping (auto-PEEP) on a flow-time scalar?