Oxygen therapy & respiratory calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). A patient breathes 20 times a minute with a tidal volume of 370 mL. Find the minute ventilation V̇E in L/min.

Practice exercise (made-up values, not clinical guidance). The gauge on a size H oxygen cylinder reads 1300 psi. Its cylinder factor is 3.14 L/psi. How many litres V can be used before the safe residual of 200 psi is reached?

Practice exercise (made-up values, not clinical guidance). A size D oxygen cylinder (factor 0.16 L/psi) reads 750 psi and runs at 10 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 139 g/L, SaO₂ 98% and PaO₂ 98 mmHg (13.1 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 cylinder with a water capacity of 2 L is filled to 126 bar and runs at 10 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 ventilated man is 170 cm tall and weighs 86 kg. Lung-protective ventilation is set at 6 mL per kg of predicted body weight. Using PBW = 50 + 0.91 × (height cm − 152.4) kg, find the tidal volume V_T to the nearest mL.