Ventilator Change from ABG Quiz
Read the gas and the current settings, then pick the single best change — ten cases per round.
Case 1 of 10
Arterial blood gas
pH
7.25
PaCO₂ mmHg
61
PaO₂ mmHg
89
SpO₂ %
94
Current ventilator settings (AC/volume control)
FiO₂
40%
Set rate
13
VT mL
430
PEEP
5
Written by Apex Respiratory Editorial Team
About this quiz
Each round draws ten cases — an arterial blood gas plus the current ventilator settings — and asks for the single best next change. Work it in two steps: fix ventilation first (a respiratory acidosis needs more minute ventilation — raise the rate; a respiratory alkalosis needs less), then fix oxygenation (raise the FiO₂ while it still has room, add PEEP once the FiO₂ is already high, and wean the FiO₂ when the patient is over-oxygenated). Every case is built so only one change is clearly right — no mixed disorders where two answers are equally defensible.
Educational use only. Teaching cases isolate a single derangement to drill the interpretation-to-intervention step; real patients present mixed acid-base and oxygenation problems, and every change is confirmed with a repeat gas. Rate targets assume tidal volume and dead space are held constant. This material supports respiratory therapy education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional protocols, or physician orders. Always follow facility policies and current provider orders, and verify calculations independently before clinical use.
Sources
- Kacmarek RM, Stoller JK, Heuer AJ. Egan's Fundamentals of Respiratory Care. 12th ed. Elsevier; 2021. Ventilator management.
- Hess DR, Kacmarek RM. Essentials of Mechanical Ventilation. 4th ed. McGraw-Hill Education; 2019.