FP-C Ventilator Management and Respiratory Support 2 — Questions and Answers
Question 1: Auto-PEEP (intrinsic PEEP) in a mechanically ventilated patient is best described as:
- A deliberate PEEP increase to improve oxygenation
- Air trapping due to incomplete exhalation before the next breath (Correct answer)
- The difference between set PEEP and measured airway pressure
- High plateau pressure caused by low compliance
Correct answer: Air trapping due to incomplete exhalation before the next breath
Auto-PEEP results from air trapping when expiratory time is insufficient for complete exhalation, increasing baseline alveolar pressure.
Question 2: A patient with severe asthma is intubated and mechanically ventilated. SpO2 is 94% but bilateral breath sounds are absent. Ventilator shows high peak pressures. The FIRST action should be:
- Increase PEEP to recruit alveoli
- Disconnect from the ventilator and manually bag slowly (Correct answer)
- Administer IV furosemide for pulmonary edema
- Increase FiO2 to 1.0
Correct answer: Disconnect from the ventilator and manually bag slowly
Severe auto-PEEP causing tension physiology requires immediate disconnection to allow passive exhalation and decompress trapped air.
Question 3: A high-pressure alarm is triggered on the transport ventilator. Which of the following is the LEAST likely cause?
- Endotracheal tube kinking
- Right mainstem intubation
- ETT cuff deflation (Correct answer)
- Patient biting the tube
Correct answer: ETT cuff deflation
ETT cuff deflation would cause a leak and low-pressure/low-volume alarm, not a high-pressure alarm.
Question 4: Permissive hypercapnia during mechanical ventilation is defined as intentionally allowing PaCO2 to rise above normal in order to:
- Improve oxygenation by shifting the oxyhemoglobin curve
- Reduce the need for sedation during transport
- Minimize tidal volumes and ventilator-induced lung injury (Correct answer)
- Increase respiratory drive in spontaneously breathing patients
Correct answer: Minimize tidal volumes and ventilator-induced lung injury
Permissive hypercapnia accepts elevated PaCO2 as a trade-off for using lower tidal volumes that reduce ventilator-induced lung injury.
Question 5: Patient-ventilator dyssynchrony during transport is BEST identified by:
- Consistently low SpO2 despite high FiO2
- Observation of patient effort against the ventilator and irregular waveforms (Correct answer)
- High end-tidal CO2 readings
- Decreasing mean arterial pressure
Correct answer: Observation of patient effort against the ventilator and irregular waveforms
Dyssynchrony is identified by observing the patient fighting the ventilator, accessory muscle use, and irregular flow/pressure waveforms on the ventilator.
Question 6: When transporting a ventilated patient with suspected ARDS, which ventilator strategy is supported by evidence to reduce mortality?
- High tidal volumes (10-12 mL/kg IBW) with low PEEP
- Low tidal volumes (6 mL/kg IBW) with adequate PEEP (Correct answer)
- Pressure support ventilation without PEEP
- Inverse I:E ratio ventilation with no PEEP
Correct answer: Low tidal volumes (6 mL/kg IBW) with adequate PEEP
The ARDSNet protocol supports low tidal volume (6 mL/kg IBW) with PEEP titration to reduce mortality in ARDS patients.
Question 7: A transport ventilator's low-minute-volume alarm activates. Which assessment finding is MOST consistent with this alarm?
- Increased end-tidal CO2 and decreased tidal volume delivery (Correct answer)
- Decreased end-tidal CO2 and increased respiratory rate
- High peak inspiratory pressures with full tidal volumes
- Improved SpO2 and reduced work of breathing
Correct answer: Increased end-tidal CO2 and decreased tidal volume delivery
Low minute volume (reduced tidal volume or rate) means less CO2 elimination, causing ETCO2 to rise, consistent with hypoventilation.
FP-C Ventilator Management and Respiratory Support 2
Auto-PEEP (intrinsic PEEP) in a mechanically ventilated patient is best described as: