A game about keeping alive a patient who is slipping away.

HemoSim puts you behind a monitor. On the other side is a patient in shock: the pulse climbs, the pressure drops, urine output stops. You have drugs, fluids, a defibrillator and very little time. Every lever you pull changes the whole system, and almost never only in the direction you wanted.

Three ways to lose a patient

• Hypertensive heart failure: the heart won't pump and pulmonary pressure rises.

• Hemorrhage: volume drains away and compensatory tachycardia eventually gives out.

• Septic shock: resistance collapses and capillary leak empties the system from inside.

Ten variables, all coupled

Pulse, mean arterial pressure, central venous pressure, cardiac output, blood volume, systemic vascular resistance, pulmonary capillary pressure, pulmonary artery pressure, stroke work and urine output. They all move at once, and none of them moves alone.

A drug cabinet with immediate effect

Dopamine, dobutamine, epinephrine, nitroglycerin, furosemide, saline, propranolol, amiodarone, transfusion, antibiotics, the defibrillator and BIPAP ventilatory support. Turning up a vasopressor fixes the pressure and breaks something else. That's the game.

Cockpit Mode

Swap the monitor for a cockpit of analog instruments: gauges, an annunciator panel with warning lights, and a tabbed multifunction display. Workups — blood gas, blood count, echocardiogram, lactate, Swan-Ganz catheter — are requested and take a few seconds to come back. As in real life, you can't read what you haven't measured. The Swan-Ganz unlocks three gauges that stay dark until then. Switch interfaces mid-run without losing the patient.

Free Mode and Exam Mode

In Free Mode you pick the condition or leave it to chance, and score on difficulty and speed: up to +7 if the patient pulls through, −10 if not. Exam Mode chains ten cases back to back and grades you on the average. It is harder than it looks.

Disclaimer

HemoSim is a video game. It is not a teaching or instructional tool and must not be used to make clinical decisions of any kind. The formulas are deliberately simplified, and doses, timings and patient responses were tuned to make the game work as a game, not to resemble reality.

Free software. Pablo Kessler.

Legal notice

HemoSim is an entertainment video game. It is not a medical device, a teaching or instructional tool, or a source of clinical information. The author accepts no responsibility for any use of it beyond entertainment.