Oxygen therapy & respiratory calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). A patient breathes 27 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 team wants an inspired oxygen of about 41% 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 ventilated patient who meets the other Berlin criteria for ARDS has PaO₂ 67 mmHg (8.9 kPa) on 100% oxygen with a PEEP of 10 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 patient has Hb 169 g/L, SaO₂ 96% and PaO₂ 80 mmHg (10.7 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 has Hb 135 g/L, SaO₂ 98%, PaO₂ 100 mmHg (13.3 kPa) and a cardiac output of 8 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.

Practice exercise (made-up values, not clinical guidance). A transfer will take 60 minutes. The size D cylinder (factor 0.16 L/psi) reads 1100 psi. Keeping a safe residual of 200 psi, what is the highest whole-number flow Q in L/min that lasts the whole transfer?