AIRCHILL · Development-stage medical technology
Controlled cooling, built into ventilation.
AIRCHILL is a development-stage transport ventilator that additionally cools the patient through the airway, intended for use from the first minutes on scene. The mechanism is published and peer-reviewed. Clinical benefit is a hypothesis, not a finding.
German Resuscitation Register, public annual report 2024: 27,009 documented out-of-hospital resuscitations in a covered population of approximately 42.07 million; incidence in the quality-assured reference group 80.08 per 100,000 population per year; the register extrapolates 54,000–67,000 resuscitations per year for Germany. Shockable rhythm 22.5 %, bystander CPR 52.0 %.
The device
One stack. Ventilation, cooling, monitoring, one detachable control unit.
This is the design concept for the AIRCHILL platform — a rendering, not a photograph of a finished device. It shows what the platform is being designed to be. What exists today is the laboratory demonstrator that carried the preclinical experiments, conservatively rated at TRL ≈ 4.
Design concept · rendering 2019 · not an approved product
The vision is a single stack that replaces the equipment an emergency team carries today. The investable first step is deliberately smaller: ventilation plus cooling, and nothing else.
- VentilationTransport ventilation with controlled respiratory cooling in one gas path — the first product, and the only part under an active product claim.
- Control unitA detachable handheld unit for the working position at the patient, so the platform does not have to be reached over.
- MonitoringPatient monitoring, ECG and defibrillation are planned as OEM modules after the MVP. They are not part of the current product claim.
- Build stateNo design freeze, no CE marking, no approval for patient use.
Rendering of the design concept, created in 2019. It illustrates the intended platform, not the current build state, and no functional claim is derived from it. Ventilation with controlled respiratory cooling is the MVP; suction, ECG, defibrillation and telemedicine are deferred. Product concept in detail.
Why now
The large trials answered a different question.
TTM2 randomised patients a median of 136 minutes after return of circulation, and then needed a median of three more hours to reach 34 °C — target temperature roughly five hours after the event. What it tested was late temperature control against fever control, and there it found no benefit. What it did not test, and cannot speak to, is cooling that begins in the first minutes on scene. That question is still open.
Cooling starts hours late
Established cooling workflows are equipment-intensive and begin after transport or on hospital arrival. The window nobody has tested properly is the one before that.
Use the pathway already in place
Every intubated emergency patient is already being ventilated. AIRCHILL investigates whether controlled cooling can ride on that pathway instead of adding a second device.
Claims follow data
Mechanism, airway safety, technical performance and patient outcome are four separate gates. We do not use evidence from one to argue for another.
Mechanism
Proof of mechanism — measured, published, and bounded.
The work below was carried out at the Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, under BMBF Go-Bio grant 031A530, with Fabian Temme as co-author. It establishes a measurable temperature effect and preclinical airway safety. It does not establish patient benefit.
MRI thermometry of a healthy volunteer before, during and after high-flow cold air delivery. The blue region marks the anterior brain during cooling; the effect resolves afterwards. Measured in two volunteers across three experiments — −0.33 °C in the inferior frontal gyrus, significant in every experiment (p < 0.05). The three other regions did not change.
ISMRM 24th Annual Meeting, Singapore 2016, Magna cum laude poster award. Conference-abstract level; not a patient study.
Histology of porcine lung after six hours of ventilation with air at −20 °C through an endotracheal tube. All structures histomorphologically intact — bronchiole, cartilage, blood vessels, alveoli. No pulmonary oedema on CT, lung perfusion unchanged on MRI and DSA.
Final report, BMBF grant 031A530, University Medical Center Hamburg-Eppendorf, 28 March 2017: “Sicherheitsbedenken sind aus unseren Untersuchungen nicht abzuleiten.”
Sedlacik J, Kjørstad Å, Nagy Z, Buhk JH, Behem CR, Trepte CJ, Fiehler J, Temme F. Feasibility Study of a Novel High-Flow Cold Air Cooling Protocol of the Porcine Brain Using MRI Temperature Mapping. Therapeutic Hypothermia and Temperature Management, doi 10.1089/ther.2017.0031 · Final report “Airchill – Gekühlte Beatmung”, BMBF grant 031A530, Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, 28 March 2017 · Kjørstad Å, Temme F, Fiehler J, Sedlacik J, ISMRM 24th Annual Meeting, Singapore 2016.
Measured values
Every number we have, and where it comes from.
The project studied 14 pigs across two experimental series and 11 healthy volunteers at University Medical Center Hamburg-Eppendorf under BMBF Go-Bio 031A530. Each measured value below carries the published subset it comes from, because mixing the project size with a single result would overstate both. All of it is preclinical, and we show the numbers that argue against us as well.
MR thermogram of the porcine brain with cooling off at ten minutes and on at twenty. The anteroposterior gradient is what produces the difference between −0.83 and −0.03 °C in the table above.
Sedlacik J et al., Therapeutic Hypothermia and Temperature Management, doi 10.1089/ther.2017.0031.
An intracerebral probe placed through a burr hole recorded the same effect during endonasal cold air ventilation, and MRI and probe measurements agreed. Temperature falls within minutes and returns afterwards.
Go-Bio final report, BMBF grant 031A530, University Medical Center Hamburg-Eppendorf, 28 March 2017.
Sedlacik J, Kjørstad Å, Nagy Z, Buhk JH, Behem CR, Trepte CJ, Fiehler J, Temme F. Feasibility Study of a Novel High-Flow Cold Air Cooling Protocol of the Porcine Brain Using MRI Temperature Mapping. Therapeutic Hypothermia and Temperature Management, doi 10.1089/ther.2017.0031 · Final report “Airchill – Gekühlte Beatmung”, BMBF grant 031A530, Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, 28 March 2017 · Kjørstad Å, Temme F, Fiehler J, Sedlacik J, ISMRM 24th Annual Meeting, Singapore 2016.
What we found against ourselves
The route we differentiate on is the weaker one.
“Die erreichte Kühlleistung auf die Zielorgane war gering bzw. lokal begrenzt — mutmaßlich auf die Totraumventilation zurückzuführen.”
That sentence is from our own final report, about the endotracheal route — the very route AIRCHILL uses to differentiate itself from transnasal devices. The report recommends the endonasal route instead. We publish this because any serious due diligence will find it, and because it defines the engineering problem precisely: dead-space ventilation is a design constraint, not a law of physics. Flow, temperature, timing and circuit geometry were not optimised in 2017.
RhinoChill has carried a CE mark for prehospital transnasal cooling since April 2011 and missed its primary endpoint in PRINCESS (n = 677). Taccone et al., Crit Care 2024;28:335 filtered the HACA-like shockable subgroup out of TTM2 (n = 600) and found no advantage there either. And our own Go-Bio report measured low cooling performance for the endotracheal route. All three are stated openly in our deck, our business plan and on this site.
Development
Three gates from thermodynamics to patient benefit.
Each gate is scoped, costed and falsifiable. Nothing below is financed yet — these are the packages the round is being raised for. Timings, sample sizes and amounts are management planning assumptions, not commitments.
Bench and airway safety
Temperature, flow, FiO₂, humidity, condensation, pressure, oxygen compatibility, transport and vibration, ISO 18562.
First-in-patient feasibility
Planning range 40–80 patients. Technical performance, process integration, airway safety and temperature-related endpoints.
Confirmatory study
Planning range 300–600 patients. Final sample size only after effect size and event rate are known; patient-relevant endpoints.
Gates, periods and sample sizes: management planning, Medical Cooling investor deck 2026. An early market entry is planned around a narrow performance and safety claim; a neurological outcome claim requires a separate and substantially larger evidence pathway.
Investors
Capital follows evidence, not the other way round.
The current round is modelled at € 7.5 million over 30 months, with an indicative € 10–15 million follow-on after Gate B. The base case carries no commercial revenue through 2031 — a deliberate modelling boundary, not a forecast.
€ 7.5m · 30 months
Team and regulatory affairs, engineering, verification and validation, preclinical preparation.
€ 10–15m indicative
After Gate B. Amount and timing are not committed.
€ 12 / 17 / 24m
Low, base and high management planning bands. No quotations obtained.
Plan and model on request
Business plan in bank, development-bank and venture versions, plus the 2027–2031 financial model.
Non-profit support
Medical Cooling is supported by Ethical Saving gUG.
Ethical Saving gUG supports Medical Cooling in building and developing AIRCHILL, and in the work towards reimbursement. It is a German gemeinnützige company — a charitable legal form whose purpose is fixed in its statutes and whose profits cannot be distributed to owners. That support is why work on an unanswered clinical question could continue through the years when it carried no commercial case.
It also covers the part no investor funds early. There is no reimbursement mechanism for a prehospital device in Germany: equipment is financed through the user charges of just under 300 emergency service districts, and there is no DRG-style payment. Establishing the health-economic case for that is slow, unglamorous and has no return — which is exactly what a charitable company is for.
Donations fund bench work, preclinical safety, study preparation, the reimbursement groundwork and the open publication of results, including the results that argue against us. A donation is not an investment. It buys no share, no return and no influence over what we publish.
Interactive prototype
Test the Medical Cooling UI.
The current interface prototype is embedded here for direct testing. It is a development UI and not an approved medical device.
If the prototype server blocks embedding, open ui.medicalcooling.com directly.
Global activities
Medical Cooling around the world.
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Build the next evidence gate with us.
We are looking for clinical investigators, engineering and manufacturing partners, regulatory expertise and long-term medical technology investors.