Tools
RT Tools & Calculators
Every calculator shows its formula with the result, cites its sources on the page, and ships only after its test suite passes against published reference values. Practice tools score each round and explain every option.
Calculators & Scales
21 calculatorsRun the numbers, see every formula
ABG interpretation, P/F ratio, A–a gradient, predicted body weight, RSBI, compliance, tank duration, and more — each formula shown with the result.
Open Calculators & Scales →Practice & Quizzes
10 trainersDrill until it's automatic
Board-style ABG interpretation and mechanical ventilation practice — scored rounds with a rationale for every option, right and wrong.
Open Practice & Quizzes →Ventilator & Weaning Math
The numbers RTs run at the bedside — protective volumes, mechanics, and readiness to wean.
IBW / Predicted Body Weight
Predicted body weight by the Devine/ARDSnet formulas with the full 4–8 mL/kg lung-protective tidal volume table.
Minute Ventilation Calculator
V̇E = RR × VT with optional alveolar ventilation — normal ranges and what high or low values mean at the bedside.
Desired Minute Ventilation Calculator
Set the ventilation to reach a target PaCO₂ — Desired V̇E = (Current V̇E × Current PaCO₂) ÷ Desired PaCO₂, with the rate to set (VT held constant), the formula shown, and an auto-PEEP caution.
Static & Dynamic Compliance
Cstat, Cdyn, and airway resistance from ventilator pressures — separates stiff-lung problems from airway-resistance problems.
Airway Resistance (Raw) Calculator
Airway resistance from ventilator pressures — Raw = (PIP − Pplat) ÷ flow (L/s), the L/min→L/s conversion and formula shown, with the intubated-adult reference range and the resistance-vs-compliance teaching contrast.
Driving Pressure (ΔP) Calculator
The pressure swing the lung sees each breath — ΔP = Plateau − PEEP (and VT ÷ Cstat) with the ≤ 14–15 cmH₂O protective target, the formula shown, and the mortality association in ARDS.
Mean Airway Pressure (P̄aw) Calculator
Mean airway pressure from ventilator settings — P̄aw = K × (PIP − PEEP) × (Ti/Ttot) + PEEP with the waveform constant (1.0 pressure-control, 0.5 constant-flow), the I:E derivation and formula shown, and the oxygenation-vs-barotrauma trade-off.
RSBI Calculator
Rapid Shallow Breathing Index (f/VT) with the Yang-Tobin 105 threshold — weaning-readiness interpretation with the evidence cited.
Gas Exchange & Oxygenation
Interpret gases and quantify oxygenation in seconds, with every formula shown.
ABG Interpreter
Stepwise arterial blood gas interpretation — primary disorder, compensation with Winter's formula and expected-compensation math shown, plus an oxygenation check.
P/F Ratio Calculator
PaO₂ ÷ FiO₂ with Berlin-definition severity bands — mild, moderate, and severe ARDS ranges with the formula shown.
S/F Ratio Calculator (SpO₂/FiO₂)
The noninvasive P/F surrogate — S/F = SpO₂ ÷ FiO₂ with the 2023 global-definition ARDS bands (315 / 235 / 148), the formula shown, and the critical SpO₂ ≤ 97% reliability caveat.
A–a Gradient Calculator
Alveolar–arterial oxygen gradient via the alveolar gas equation, with age-expected normals and every step of the math shown.
Oxygen Content (CaO₂) Calculator
Arterial oxygen content from hemoglobin, SaO₂, and PaO₂ — CaO₂ = (1.34 × Hb × SaO₂) + (0.003 × PaO₂), the formula shown, with the bound-vs-dissolved split and why content tracks hemoglobin, not PaO₂.
Physiologic Shunt (Qs/Qt) Calculator
Intrapulmonary shunt fraction — the classic three-content Berggren equation Qs/Qt = (CcO₂ − CaO₂) ÷ (CcO₂ − CvO₂), or the estimated form with an assumed C(a-v)O₂, with the alveolar PO₂ derived and every oxygen content shown.
ROX Index Calculator
Predict high-flow nasal cannula success — ROX = (SpO₂ ÷ FiO₂) ÷ RR with the validated 4.88 and 3.85 thresholds, the formula shown, and the trend-over-time caveat.
Oxygenation Index (OI) Calculator
Severity of hypoxemic respiratory failure including ventilator support — OI = (FiO₂ × mean airway pressure × 100) ÷ PaO₂ with the PALICC pediatric ARDS bands and the ECMO-consideration threshold, the formula shown.
Dead Space Fraction (VD/VT) Calculator
Bohr-Enghoff dead space — VD/VT = (PaCO₂ − P̄ECO₂) ÷ PaCO₂ with normal ranges, the formula shown, and what a markedly elevated value means (PE, ARDS, low cardiac output).
Oxygen Delivery
Plan transport and therapy with confidence.
Oxygen Tank Duration
Cylinder duration from gauge pressure, tank factor (D, E, G, H/K, M), flow, and a safe residual — built for transport planning.
Air-Entrainment Ratio & Total Flow Calculator
Air-entrainment ('Venturi') mask math — air:O₂ ratio = (100 − FiO₂%) ÷ (FiO₂% − 21) and total flow = (air parts + 1) × O₂ flow, the formula shown, with the standard taught ratios and a check against inspiratory demand.
Pulmonary Function
Quantify spirometry change against the published criteria, with the math shown.
Labs & Diagnostics
Bedside lab math with the formula shown — interpret the gas and the metabolic panel together.
Practice & Quizzes
Board-style practice
Scored rounds with a rationale for every option. More banks ship as the library grows.
ABG Interpretation Quiz
Drill arterial blood gas pattern recognition — read a fresh pH/PaCO₂/HCO₃ panel each round and name the primary acid-base disorder, with an instant rationale and scored ten-question rounds.
PFT Pattern Quiz
Drill pulmonary function test interpretation — read FEV₁, FVC, FEV₁/FVC, and TLC each round and name the pattern (obstructive, restrictive, mixed, or normal), with an instant rationale and scored ten-question rounds.
Oxygenation & ARDS Severity Quiz
Drill oxygenation severity — read a PaO₂ and FiO₂ each round, compute the P/F ratio, and classify the Berlin ARDS band (none, mild, moderate, or severe), with an instant rationale and scored ten-question rounds.
Shock Type Quiz
Drill shock classification — read a hemodynamic profile (CVP, PCWP, cardiac output, SVR) each round and name the shock category (hypovolemic, cardiogenic, obstructive, or distributive), with an instant rationale and scored ten-question rounds.
ABG Compensation Quiz
Drill the harder half of ABG interpretation — read a pH/PaCO₂/HCO₃ panel each round and judge the compensation status (uncompensated, partially compensated, fully compensated, or a mixed disorder), with an instant rationale and scored ten-question rounds.
Ventilator Waveform Quiz
Read fresh pressure, flow, and volume scalars each round and name the pattern — normal, increased airway resistance, decreased compliance, auto-PEEP, circuit/cuff leak, or flow starvation — with an instant rationale, the alarm each triggers, and scored ten-question rounds.
Air-Entrainment (Venturi) Quiz
Drill Venturi mask math — read a fresh FiO₂ (and O₂ flow) each round and compute the air-to-oxygen entrainment ratio or the total delivered flow from the formula, with an instant rationale and scored ten-question rounds.
Capnography Waveform Quiz
Drill EtCO₂ capnogram interpretation — read a fresh CO₂ waveform each round and name the pattern (normal, hypoventilation, hyperventilation, shark-fin obstruction, curare cleft, rebreathing, esophageal/absent, sudden loss, or ROSC), with an instant rationale and scored ten-question rounds.
Ventilator Change from ABG Quiz
Drill the interpretation-to-intervention step — read a fresh arterial blood gas and the current ventilator settings each round and pick the single best change (rate, FiO₂, or PEEP), with an instant rationale and scored ten-question rounds.
Free TMC Practice Sampler
Ten free NBRC TMC-style questions spanning all three matrix categories — patient data, equipment troubleshooting, and initiation & modification — across mechanical ventilation, ABG & acid-base, oxygen therapy, pharmacology, and airway, each with a rationale for every option.