Oxygen therapy & respiratory calculations worksheet with answers

Free printable Oxygen therapy & respiratory calculations worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
0123456L/minFiO₂ ≈ ?21% + 4%·L/min

Practice exercise (made-up values, not clinical guidance). A patient receives oxygen by nasal cannula at 2 L/min. Using FiO₂ ≈ 21% + 4% per L/min, estimate the inspired oxygen FiO₂ in percent.

2 L/min
FiO₂ = %
2.Easy
0123456L/minFiO₂ ≈ ?21% + 4%·L/min

Practice exercise (made-up values, not clinical guidance). A patient receives oxygen by nasal cannula at 3 L/min. Using FiO₂ ≈ 21% + 4% per L/min, estimate the inspired oxygen FiO₂ in percent.

3 L/min
FiO₂ = %
3.Medium
Hb126 g/LSaO₂98%PaO₂106 mmHgCaO₂?

Practice exercise (made-up values, not clinical guidance). A patient has Hb 126 g/L, SaO₂ 98% and PaO₂ 106 mmHg (14.1 kPa). Find the arterial oxygen content CaO₂ = 1.34 × Hb (g/dL) × SaO₂ + 0.003 × PaO₂ (mmHg) in mL O₂/dL.

Hb 126 g/LSaO₂ 98%PaO₂ 106 mmHg (14.1 kPa)
CaO₂ = mL/dL
4.Medium
PaO₂ 52 mmHg · FiO₂ 0.8 · PEEP 14 cmH₂O0100200300400500P/F (mmHg)above 300: no ARDS grademildmoderatesevere

Practice exercise (made-up values, not clinical guidance). A ventilated patient who meets the other Berlin criteria for ARDS has PaO₂ 52 mmHg (6.9 kPa) on 80% oxygen with a PEEP of 14 cmH₂O. Calculate the P/F ratio and click the ARDS severity.

PaO₂ 52 mmHg (6.9 kPa)FiO₂ 80%PEEP 14 cmH₂O
  1. 1above 300: no ARDS grade
  2. 2mild
  3. 3moderate
  4. 4severe
5.Hard
1450psiDf = 0.16 L/psi90 minresidual 200 psiQ = ? L/min

Practice exercise (made-up values, not clinical guidance). A transfer will take 90 minutes. The size D cylinder (factor 0.16 L/psi) reads 1450 psi. Keeping a safe residual of 200 psi, what is the highest whole-number flow Q in L/min that lasts the whole transfer?

90 min1450 psif = 0.16 L/psi200 psi
Q = L/min
6.Hard
SpO₂ 89% · FiO₂ 0.4ROX = ?RR 31/minROX = (SpO₂/FiO₂)/RR

Practice exercise (made-up values, not clinical guidance). A patient on high-flow nasal oxygen has SpO₂ 89% on FiO₂ 0.4 and a respiratory rate of 31/min. Find the ROX index ROX = (SpO₂/FiO₂)/RR, with SpO₂ in percent and FiO₂ as a fraction. Round to two decimal places.

SpO₂ 89%FiO₂ 0.4RR 31/min
ROX =

Answer key

  1. 1. FiO₂ = 29 %
  2. 2. FiO₂ = 33 %
  3. 3. CaO₂ = 16.86 mL/dL
  4. 4. severe
  5. 5. Q = 2 L/min
  6. 6. ROX = 7.18

Full step-by-step solutions: practise this topic on examproblems.com.