Oxygen therapy & respiratory calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). The team wants an inspired oxygen of about 25% 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.)

Practice exercise (made-up values, not clinical guidance). A patient breathes 32 times a minute with a tidal volume of 410 mL. Find the minute ventilation V̇E in L/min.

Practice exercise (made-up values, not clinical guidance). A patient has Hb 98 g/L, SaO₂ 98% and PaO₂ 109 mmHg (14.5 kPa). Find the arterial oxygen content CaO₂ = 1.34 × Hb (g/dL) × SaO₂ + 0.003 × PaO₂ (mmHg) in mL O₂/dL.

Practice exercise (made-up values, not clinical guidance). A ventilated patient who meets the other Berlin criteria for ARDS has PaO₂ 97 mmHg (12.9 kPa) on 45% oxygen with a PEEP of 12 cmH₂O. Calculate the P/F ratio and click the ARDS severity.

1. 1above 300: no ARDS grade
2. 2mild
3. 3moderate
4. 4severe

Practice exercise (made-up values, not clinical guidance). A cylinder with a water capacity of 10 L is filled to 72 bar and runs at 12 L/min. The gas volume is about the water capacity × the pressure. In this exercise the cylinder is changed at 20 bar. How many minutes t until it must be changed? Round down to a whole minute.

Practice exercise (made-up values, not clinical guidance). A cylinder with a water capacity of 3 L is filled to 195 bar and runs at 12 L/min. The gas volume is about the water capacity × the pressure. In this exercise the cylinder is changed at 20 bar. How many minutes t until it must be changed? Round down to a whole minute.