The Ventilator Simulator

Educational model — an idealized single-compartment lung. It is not a medical device, not for clinical use, and not a substitute for a ventilator’s operator’s manual or for clinical judgment.

Everything else in this guide explains the waveforms; this page lets you make them. Drag a slider and the pressure, flow, and volume tracings redraw instantly — because each curve is solved, live, from the one equation the rest of the guide is built on:

P_vent + P_mus = V/C + R·V̇ + PEEP

Change the lung (compliance, resistance) or the ventilator (mode, PEEP, rate, tidal volume or driving pressure, inspiratory time, flow-cycle threshold), add a patient effort, and watch the same cause-and-effect the chapters describe play out on the graph.

▶ Open the simulator full screen ↗

(If the interactive panel above does not appear, use the Open full screen link — some readers block embedded frames.)

What to try

A few experiments that make the guide’s ideas concrete:

• Stiffen the lung (drop compliance, or hit the ARDS preset). In volume control the peak and plateau pressures climb while the delivered volume is unchanged — you set the volume, the lung charges you in pressure. This is the read-the-load-off-pressure rule in action.
• Obstruct the airway (raise resistance, or the COPD preset) in pressure control. Flow decelerates more slowly, the time constant τ = R·C lengthens, and volume takes longer to fill — the exponential behaviour from the mechanics chapter.
• Switch VC ↔ PC at the same settings and watch which waveform is a clean square (the controlled variable) and which one carries the patient (the one you read) — the whole point of the control variable.
• Add a patient effort (raise P_mus, or the Flow starvation preset). In volume control the effort scoops the pressure curve concave; in pressure control it adds flow and volume above the passive breath — the two signatures of work-shifting from the interaction chapter.
• Weaning (PSV): every breath is patient-triggered and flow-cycled — move the cycle-off threshold and watch inspiration end earlier or later.

How this model works (and where it stops)

The simulator is the same physics engine that drew the static reference figures in the other chapters, run in your browser instead of ahead of time. It solves the single-compartment equation of motion — one resistance in series with one elastance — exactly as described in [Chatburn 2007] and [Chatburn 2026 · Waveforms]: volume control prescribes a square flow and reads pressure off the equation; pressure control prescribes a square pressure and integrates the resulting decelerating flow and exponential volume; pressure support adds a flow-cycle criterion. A patient effort is layered in as a second forcing term, exactly as the waveform-reading method frames it [Mireles-Cabodevila 2022].

Its limits are the limits of the model, and they matter. It is a single compartment — real lungs are many regions with different mechanics. It assumes linear, constant resistance and elastance, ideal triggering and cycling, and no circuit leaks, tubing compliance, secretions, or noise. It is a tool for building intuition about cause and effect, not a simulation of any specific ventilator or patient. Treat it the way the corpus treats its idealized tracings: as the comparator you learn first, against which real, messier waveforms are read.

How this chapter connects

• The equation it solves is derived in Respiratory Mechanics and the Equation of Motion.
• Naming the mode you are simulating (VC / PC / PSV, and the targeting scheme) is The Taxonomy of Ventilator Modes.
• Reading the load off the waveform opposite the control variable — the skill the simulator lets you rehearse — is Reading Ventilator Waveforms.
• The patient-effort deformations (scooping, extra flow) are the work-shifting signatures from Patient-Ventilator Interaction and Discordance.
• Learning all of this to mastery on a simulator is the method of Learning Mechanical Ventilation - The SEVA Program.

Sources

The model implements the equation of motion and the mode behaviours described in the frozen, human-reviewed primary literature:

• [Chatburn 2007] — Chatburn RL. Classification of ventilator modes: update and proposal for implementation. Respir Care 2007. PMID 17328828.
• [Mireles-Cabodevila 2022] — Mireles-Cabodevila E, Siuba MT, Chatburn RL. A Taxonomy for Patient-Ventilator Interactions and a Method to Read Ventilator Waveforms. Respir Care 2022. PMID 34470804.
• [Chatburn 2026 · Waveforms] — Chatburn RL. How to interpret ventilator waveforms using the taxonomy for modes of mechanical ventilation. 2026. PMID 41631602.

This is an original, in-house model built from the public equation of motion; it uses no patient data and no device firmware, and reproduces no copyrighted figure from the source papers.