Oxygen therapy & respiratory calculations worksheet with answers

Practice exercise (made-up values, not clinical guidance). A patient breathes 17 times a minute with a tidal volume of 450 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 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 ventilated patient who meets the other Berlin criteria for ARDS has PaO₂ 67 mmHg (8.9 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 patient has Hb 114 g/L, SaO₂ 88% and PaO₂ 55 mmHg (7.3 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 on high-flow nasal oxygen has SpO₂ 89% on FiO₂ 0.55 and a respiratory rate of 20/min. Find the ROX index ROX = (SpO₂/FiO₂)/RR, with SpO₂ in percent and FiO₂ as a fraction. Round to two decimal places.

Practice exercise (made-up values, not clinical guidance). A patient has Hb 111 g/L, SaO₂ 98%, PaO₂ 104 mmHg (13.9 kPa) and a cardiac output of 7.9 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.