Oxygen therapy & respiratory calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). The gauge on a size E oxygen cylinder reads 1200 psi. Its cylinder factor is 0.28 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). 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.)

Practice exercise (made-up values, not clinical guidance). A patient breathes 24 times a minute with a tidal volume of 670 mL. The anatomical dead space is 120 mL. Find the alveolar ventilation V̇A in L/min.

Practice exercise (made-up values, not clinical guidance). A patient has Hb 143 g/L, SaO₂ 94% and PaO₂ 72 mmHg (9.6 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 transfer will take 30 minutes. The size D cylinder (factor 0.16 L/psi) reads 1950 psi. Keeping a safe residual of 200 psi, what is the highest whole-number flow Q in L/min that lasts the whole transfer?

Practice exercise (made-up values, not clinical guidance). A patient has Hb 96 g/L, SaO₂ 92%, PaO₂ 65 mmHg (8.7 kPa) and a cardiac output of 4.6 L/min. With CaO₂ = 1.34 × Hb (g/dL) × SaO₂ + 0.003 × PaO₂ (mmHg), find the oxygen delivery DO₂ = CaO₂ × CO × 10 in mL/min.