Practice exercise (made-up values, not clinical guidance). The team wants an inspired oxygen of about 33% by nasal cannula. Using the rule of thumb FiO₂ ≈ 21% + 4% per L/min, what flow Q does it suggest? (Real FiO₂ varies with the patient's breathing.)
Oxygen therapy & respiratory calculations worksheet with answers
Practice exercise (made-up values, not clinical guidance). A patient breathes 17 times a minute with a tidal volume of 610 mL. Find the minute ventilation V̇E in L/min.
Practice exercise (made-up values, not clinical guidance). A ventilated patient who meets the other Berlin criteria for ARDS has PaO₂ 49 mmHg (6.5 kPa) on 80% oxygen with a PEEP of 10 cmH₂O. Calculate the P/F ratio and click the ARDS severity.
- 1above 300: no ARDS grade
- 2mild
- 3moderate
- 4severe
Practice exercise (made-up values, not clinical guidance). A ventilated patient who meets the other Berlin criteria for ARDS has PaO₂ 110 mmHg (14.7 kPa) on 35% oxygen with a PEEP of 14 cmH₂O. Calculate the P/F ratio and click the ARDS severity.
- 1above 300: no ARDS grade
- 2mild
- 3moderate
- 4severe
Practice exercise (made-up values, not clinical guidance). A patient with acute hypoxaemia and bilateral opacities, not explained by heart failure, has PaO₂ 17.5 kPa on 45% oxygen with a PEEP of 6 cmH₂O. Grade the ARDS severity with the Berlin definition. Click your answer.
- 1above 300: no ARDS grade
- 2mild
- 3moderate
- 4severe
- 5not gradable: PEEP below 5
Practice exercise (made-up values, not clinical guidance). A patient with acute hypoxaemia and bilateral opacities, not explained by heart failure, has PaO₂ 7.3 kPa on 80% oxygen with a PEEP of 5 cmH₂O. Grade the ARDS severity with the Berlin definition. Click your answer.
- 1above 300: no ARDS grade
- 2mild
- 3moderate
- 4severe
- 5not gradable: PEEP below 5
Answer key
- 1. Q = 3 L/min
- 2. V̇E = 10.37 L/min
- 3. severe
- 4. above 300: no ARDS grade
- 5. mild
- 6. severe
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