Oxygen therapy & respiratory calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). A patient breathes 23 times a minute with a tidal volume of 720 mL. Find the minute ventilation V̇E in L/min.

Practice exercise (made-up values, not clinical guidance). A patient breathes 14 times a minute with a tidal volume of 510 mL. Find the minute ventilation V̇E in L/min.

Practice exercise (made-up values, not clinical guidance). A size E oxygen cylinder (factor 0.28 L/psi) reads 1750 psi and runs at 8 L/min. Keeping a safe residual of 200 psi, how many minutes t will it last? Round down to a whole minute.

Practice exercise (made-up values, not clinical guidance). A patient has Hb 136 g/L, SaO₂ 97% and PaO₂ 96 mmHg (12.8 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 patient with acute hypoxaemia and bilateral opacities, not explained by heart failure, has PaO₂ 17.2 kPa on 40% oxygen with a PEEP of 12 cmH₂O. Grade the ARDS severity with the Berlin definition. Click your answer.

1. 1above 300: no ARDS grade
2. 2mild
3. 3moderate
4. 4severe
5. 5not gradable: PEEP below 5

Practice exercise (made-up values, not clinical guidance). A cylinder with a water capacity of 2 L is filled to 94 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.