RPSGT Exam PAP Therapy Administration & Titration — Questions and Answers
Question 1: During a CPAP titration study, a patient continues to have obstructive apneas at 10 cmH2O. What is the recommended next step according to AASM titration guidelines?
- Immediately switch the patient to BiPAP
- Increase the CPAP pressure by 1-2 cmH2O and observe response (Correct answer)
- Apply supplemental oxygen at 2 L/min
- Terminate the study and refer for surgical evaluation
Correct answer: Increase the CPAP pressure by 1-2 cmH2O and observe response
AASM guidelines recommend incremental pressure increases (1-2 cmH2O) during titration, waiting at least 5 minutes between adjustments to allow stabilization before escalating further. Switching to BiPAP or other interventions is premature without first optimizing CPAP pressure.
Question 2: Which PAP modality delivers a higher inspiratory pressure (IPAP) and a lower expiratory pressure (EPAP), making it useful for patients who struggle to exhale against CPAP pressure?
- CPAP (continuous positive airway pressure)
- APAP (auto-titrating positive airway pressure)
- BiPAP/BPAP (bilevel positive airway pressure) (Correct answer)
- ASV (adaptive servo-ventilation)
Correct answer: BiPAP/BPAP (bilevel positive airway pressure)
BiPAP delivers two distinct pressure levels: a higher IPAP during inhalation and a lower EPAP during exhalation. This pressure differential reduces the work of exhalation and is particularly useful for patients who are intolerant of fixed CPAP pressure or have hypoventilation disorders.
Question 3: During a split-night study, what minimum criteria must typically be met before transitioning from the diagnostic to the CPAP titration portion, per AASM guidelines?
- At least 2 hours of diagnostic recording with an AHI ≥ 40 events/hour (Correct answer)
- At least 1 hour of diagnostic recording with any obstructive events
- At least 4 hours of diagnostic recording with an AHI ≥ 15 events/hour
- REM sleep must be recorded before transitioning
Correct answer: At least 2 hours of diagnostic recording with an AHI ≥ 40 events/hour
AASM guidelines specify that a split-night study requires at least 2 hours of diagnostic sleep and an AHI ≥ 40 events/hour (or AHI 20-40 with clinical justification such as severe hypoxemia) before proceeding to CPAP titration in the same night.
Question 4: A patient on CPAP therapy reports significant aerophagia (air swallowing and bloating). Which intervention is most appropriate?
- Increase CPAP pressure to reduce air leaks
- Reduce CPAP pressure or switch to BiPAP to lower mean airway pressure (Correct answer)
- Switch from nasal mask to a full-face mask
- Add supplemental oxygen to the circuit
Correct answer: Reduce CPAP pressure or switch to BiPAP to lower mean airway pressure
Aerophagia occurs when pressurized air is inadvertently swallowed rather than entering the airway. Reducing pressure or switching to BiPAP (which has a lower mean pressure due to the lower EPAP) decreases the amount of air forced into the esophagus, alleviating the symptom.
Question 5: Adaptive servo-ventilation (ASV) is most appropriate for treating which sleep-related breathing disorder?
- Primary snoring with an AHI < 5
- Obesity hypoventilation syndrome with hypercapnia
- Complex sleep apnea (treatment-emergent central apnea) or predominant central sleep apnea (Correct answer)
- REM-related obstructive sleep apnea in otherwise healthy patients
Correct answer: Complex sleep apnea (treatment-emergent central apnea) or predominant central sleep apnea
ASV continuously adjusts pressure support breath-by-breath to servo-control the patient's ventilation, targeting a recent average peak flow. It is specifically designed for complex (mixed/central-predominant) sleep apnea and Cheyne-Stokes respiration, conditions where fixed CPAP or BiPAP are insufficient.
Question 6: What is the primary purpose of the expiratory pressure relief feature (e.g., EPR, C-Flex, or A-Flex) available on some CPAP devices?
- To increase pressure during inspiration to prevent hypopneas
- To automatically increase pressure in response to detected apneas
- To slightly reduce pressure during exhalation to improve patient comfort and adherence (Correct answer)
- To deliver bilevel pressure support equivalent to BiPAP therapy
Correct answer: To slightly reduce pressure during exhalation to improve patient comfort and adherence
Expiratory pressure relief reduces the delivered pressure by 1-3 cmH2O during the exhalation phase, easing the effort required to breathe out against CPAP pressure. This comfort feature improves patient tolerance and adherence without fundamentally changing the therapeutic pressure during inhalation.
RPSGT Exam PAP Therapy Administration & Titration
During a CPAP titration study, a patient continues to have obstructive apneas at 10 cmH2O.
What is the recommended next step according to AASM titration guidelines?