Coach DrépanoCoach Drépanothe keys to autonomy

Take control of sickle cell disease, day after day.

A scientific project born from patients' experience. Coach Drépano brings together Trévor, a free health assistant, and support programmes led by expert patients and haematologists. To anticipate crises, prepare every consultation and gain autonomy.

Free, no sign-up, in ten languages. Trévor answers within seconds.

Anticipate your crisesThanks to a check-in of ten seconds to one minute, each evening. Week after week, Trévor shows the signs that precede your pain, sleep, hydration, fatigue, and helps you act before the crisis. With a connected watch or ring, Trévor also estimates your 48-hour crisis risk (beta feature at the research stage).
Reliable answers, at any hourYour questions get answers grounded in medical guidelines and in the experience of expert patients, with their sources.
Faster care in the emergency roomYour care card, to be validated by your haematologist, tells the emergency team which treatment to follow as soon as you arrive. You wait less and repeat fewer explanations.
A specialist without the waitRequest a teleconsultation with a HUG haematologist in three taps. You get an appointment quickly, without going through the switchboard.

You are…

A scientific approach, led by patients.

A scientific project

Every Trévor feature stems from a study published in a peer-reviewed journal, and the whole is undergoing clinical evaluation at Geneva University Hospitals. Content cites its sources and is reviewed by a haematologist. This work rests on ten years of research, on the team's contribution to the Lancet Haematology Commission on sickle cell disease, and on published methods that other teams can reproduce.

Designed and steered by patients

The project is directed by a patient-researcher who lives with sickle cell disease, and the people concerned decided on the features at every step, from needs to mock-ups, tests and content. This participatory design has been formalised and published; it explains why Trévor speaks the language of everyday life.

A concrete benefit, whatever your situation.

Patients

You identify your triggers, prepare your consultations with precise data and carry an emergency card that speeds up your care.

Discover Trévor →

Relatives and parents

You learn to recognise warning signs and support your loved one with guidance validated by haematologists, while protecting your own balance.

Discover Drépadémie →

Health professionals

You follow your patients between consultations, with their consent, on an interoperable FHIR dashboard, and train your team in one day.

See the training →

Trévor

Personal health assistant. In Telegram. Free.

Trévor teaches you the best self-management practices, what to do concretely and how, to live better with sickle cell disease. It draws on the collective intelligence of patients, clinicians and research, and artificial intelligence tailors each piece of advice to your situation. Designed with patients at Geneva University Hospitals. Trévor is opening up to other rare or overlooked diseases, with dedicated profiles for sickle cell disease, thalassaemia, Ehlers-Danlos syndrome and malaria, with more to come.

See Trévor's features
  • The gestures that work. Learned from other patients and validated by caregivers, on hydration, sleep, pain and crisis prevention, each explained step by step.
  • A dashboard that speaks to your doctor. Pain, sleep, hydration and treatment day after day, exportable as CSV, JSON and FHIR.
  • Immediate, sourced answers. To your questions, with referral to your team or to 144 as soon as a warning sign appears.
  • Drépadémie. Short training modules with quizzes, reviewed by a haematologist and an expert patient.
  • Goal-based coaching. Weekly, for health as well as for your life projects (studies, work, couple, family, travel), with a printable care and emergency card.
  • My life with the illness. Tell in one sentence the moments that help and those that weigh, watch them take their place on your timeline with your family, and receive a heading for the days ahead.
  • Your data under your control. Hosted in Switzerland (Infomaniak, Geneva), with logged access and one-tap deletion.

Try Trévor for free

Trévor complements medical follow-up. Beta version, evaluated at HUG as part of a research project.

Good evening Amina, time for your daily check-in. How are you tonight?
Tired, my legs hurt a bit
Out of 10, how strong is the pain?
4
Noted. 🔥 6 days in a row. Drink a glass of water now and stay warm. If the pain rises, or in case of fever or trouble breathing, call the emergency number.
📝 My daily check-in🎓 Training🎯 Coaching📈 My progress➕ More

Sickle what? The answers, and your questions.

Answers to the questions everyone asks about sickle cell disease, reviewed by a haematologist and an expert patient, with Geneva and French-speaking Switzerland first. For any other question, Trévor answers live.

The answer appears right here, in a few seconds, no account needed. Care decisions belong to your medical team; if a warning sign appears, call 144.

What is sickle cell disease?

Sickle cell disease is a genetic disorder of haemoglobin, the protein that carries oxygen in red blood cells. With haemoglobin S, red blood cells take a sickle shape when oxygen runs low, block small vessels and break down faster than normal.

The result is painful crises, chronic anaemia and, over time, organ damage that medical follow-up can detect and limit. It affects millions of people worldwide and a few hundred people followed in Switzerland.

How is it inherited?

Inheritance is genetic and comes from both parents. Each passes on one haemoglobin gene.

A person with the disease received an S gene from each parent. When both parents carry the trait (AS), each pregnancy has a one in four chance of a child with the disease (SS), one in two of a carrier (AS) and one in four of a child without the S gene (AA).

A simple blood test, haemoglobin electrophoresis, shows each person's status. In Geneva, the HUG genetics clinic supports couples who want to know their risk.

I carry the sickle cell trait (AS), am I ill?

The sickle cell trait means a single S gene. The person is healthy and lives normally, with two points to keep in mind.

The first concerns extreme situations, very intense effort without hydration, strong heat, high altitude, where rare complications have been described. The second concerns planning a child.

Knowing your partner's status, through a simple blood test, lets you decide with full knowledge, with the help of a genetics clinic.

See the other questions (14)
What forms of the disease exist?

The SS form is the most common and often the most severe. The SC form generally brings fewer crises, with particular attention to the eyes and hips.

The S beta-thalassaemia forms resemble the SS form when normal haemoglobin production is absent (Sβ0) and remain milder when it partly persists (Sβ+). Each person lives their form differently, and follow-up adapts to their history rather than to the label.

What is a vaso-occlusive crisis and what triggers it?

A vaso-occlusive crisis occurs when sickled red blood cells block circulation in a bone, a joint, the belly or the back, causing intense pain. The most frequent triggers are dehydration, cold, altitude, intense effort, fever and infections, stress, lack of sleep, alcohol and tobacco.

Spotting your own triggers, day after day, is one of the most effective ways to space out crises. That is exactly what Trévor's daily check-in helps you do.

What should I do at home when a crisis begins?

At the first signs, drink water regularly, keep warm, rest and take the painkillers planned with your doctor, at the planned times. Slow breathing, four seconds in and six seconds out for five minutes, helps release tension.

If the pain stays strong after a few hours despite this plan, or if a warning sign appears, the next step is the hospital. Trévor's care card summarises your plan for the team receiving you.

When should I go to the emergency room?

Some signs require the hospital without delay. A fever of 38.5 °C or higher.

Chest pain, cough or shortness of breath. Weakness on one side of the body, trouble speaking or a sudden severe headache.

A painful erection lasting more than two hours. In a child, sudden pallor with a swelling belly.

Pain that your usual plan leaves untouched. In Geneva and Switzerland, 144 sends an ambulance; in France, 15.

Saying "I have sickle cell disease" on arrival speeds up care, and Trévor's care card says it for you.

What is acute chest syndrome?

Acute chest syndrome is a lung complication combining fever, chest pain, cough and shortness of breath, often in the days following a crisis. It is an emergency treated in hospital, with oxygen, antibiotics and sometimes transfusion.

During a crisis, breathing deeply every hour, if needed with a small device called an incentive spirometer, drinking enough and moving as soon as possible reduce the risk of it appearing.

What treatments exist today?

The most widely used background treatment is hydroxyurea, a daily tablet that spaces out crises. Transfusions and exchange transfusions protect in high-risk situations and prevent certain complications, such as stroke in children.

Other targeted drugs exist or are under study depending on the country. Bone marrow transplantation and, since late 2023 in several countries, gene therapies aim at a cure, with access still limited to severe forms.

The choice is made with the haematologist, according to your history.

What is hydroxyurea and what is it for?

Hydroxyurea, also called hydroxycarbamide, increases the production of fetal haemoglobin, a haemoglobin that keeps red blood cells from deforming. Taken every day, it reduces the number of crises, acute chest syndromes and transfusions, and improves survival.

It requires regular blood tests to adjust the dose, and contraception is discussed during treatment. Long-term studies confirm its safety in children and adults alike.

What medical follow-up, and how often?

A specialist consultation at least once a year, with a blood test, forms the foundation. Regular screenings are added, an eye exam, a check of the kidneys, heart and lungs, and in children a yearly transcranial Doppler to prevent stroke.

Vaccinations, particularly against pneumococcus, meningococcus and flu, protect a spleen that works poorly. In Geneva, this follow-up takes place at the HUG haematology department for adults and in paediatrics for children; in French-speaking Switzerland, at the CHUV in Lausanne.

Can sickle cell disease be cured?

Yes, in certain situations. Bone marrow transplantation from a compatible brother or sister cures more than nine children out of ten, with risks that justify reserving it for severe forms.

Gene therapies, which modify the person's own stem cells, have been authorised in several countries since late 2023 and are subject to gradual, supervised access. For the vast majority of people, life with the disease is organised around a background treatment, regular follow-up and solid self-management.

How much should I drink, and how should I eat?

An adult aims for two to three litres of water a day, more in heat, effort or fever, unless the doctor sets a restriction. A bottle always within reach makes it simple.

On the plate, regular and varied meals, rich in fruit, vegetables and pulses, cover the increased needs for energy and folate, often supplemented by a folic acid prescription. Alcohol dehydrates and triggers crises; tobacco damages lungs that are already exposed.

Sport, travel, flying, altitude?

Regular, moderate physical activity does good, with a warm-up, water within reach and breaks before exhaustion. Extreme efforts and breath-hold sports are discussed with the doctor.

On a plane, the cabin is equivalent to an altitude of 1,800 to 2,400 metres. Drinking about 250 ml of water per flight hour, getting up and walking every hour, wearing compression stockings on flights over four hours, covering up against the cabin cold and keeping painkillers in your hand luggage form the basis.

For severe forms, a history of acute chest syndrome or a low oxygen saturation, the doctor prescribes supplemental oxygen, supplied by the airline on request to its medical service or through a personal portable oxygen concentrator accepted with a medical form. For the same situations, the haematologist may propose an exchange transfusion before departure or, failing that, a simple transfusion, which lowers the share of haemoglobin S.

A flight is postponed during a crisis or a fever. Above 1,500 metres in the mountains, caution is required.

Before a long trip, the HUG travel clinic checks vaccines, malaria prevention and prepares a medical letter.

School and work, what rights in Switzerland?

At school, in Geneva, the individual support plan (PAI) is requested from the Child and Youth Health Service (SSEJ) with the treating doctor; it sets access to water, toilets, rest and the steps to follow during a crisis. In other French-speaking cantons, the request goes through the school nurse.

At work, adjustments are negotiated with the employer, and disability insurance (AI) steps in when the disease limits work capacity, with training measures, pensions or a helplessness allowance. In France, the PAI is requested from the school doctor and the MDPH opens rights.

Pregnancy and contraception?

Pregnancy is possible and needs preparation. Follow-up starts from the beginning, jointly by the haematologist and the obstetrician, because the risks of crisis, anaemia and complications are higher.

Some treatments, including hydroxyurea, are stopped before conception, which makes planning valuable. For contraception, progestin-only methods and the IUD are often preferred; the choice is made with the doctor.

In Geneva, the HUG maternity works in direct contact with haematology.

Where can I find help in Geneva and French-speaking Switzerland?

In Geneva, the HUG haematology department follows adults and the paediatrics department follows children; the Association Suisse Drépano brings together people concerned, organises meetings and defends their rights. In French-speaking Switzerland, the CHUV in Lausanne plays the same reference centre role.

For an emergency, 144. For a question at any hour, Trévor answers on Telegram, with its sources, and refers you to the care team as soon as a warning sign appears.

Measure, to act in time.

Your watch or ring records at night the signals that escape your attention, oxygen saturation that drops, a heart that speeds up at rest, sleep that fragments. Trévor turns them into readable curves, compares each week with your average and warns you as soon as something is out of the ordinary. At the consultation, you bring dated facts, and your care team acts earlier.

  • Sleep. Duration and regularity of your nights, week after week.
  • Oxygen. Night-time saturation, invisible without a sensor, documented for your doctor.
  • Heart. Resting heart rate, day after day, to show your team.
  • Compatibility. Samsung, Apple, Google, Fitbit, Oura, Garmin, Withings; single-file import or automatic sync.

“My watch revealed night-time hypoxia.
After a few investigations with my haematologist, including a polysomnography, its readings led to a prescription for night-time oxygen therapy at home and two portable concentrators, one for home, the other for air travel, high altitude or intense sport.
It changed my life.”

Dr David-Z. Issom, HES Professor, founder of Coach Drépano, living with sickle cell disease.
Case presented at the Swiss Tropical and Public Health Institute (Swiss TPH).

Why you can trust it.

Every step was carried out with the people concerned, published and evaluated, through work conducted since 2018 between Geneva and the Caribbean.

2018

DREPACOACH, the first support app designed with patients (HUG, University of Geneva).

2021

Publication of Trévor's design and usefulness study in Frontiers in Digital Health.

2022

“Quality of care” project at HUG, with emergency card, educational content and a link to HUG@Home.

2026-2027

Trévor renewed, evaluated at HUG by the TREVOR-PILOTE study. The haematology teleconsultation and adapted physical activity join Trévor over this period.

From 2027

The LifeRover study aims to follow families over several years to understand the factors of a better life with sickle cell disease, at school, at work and at home. In Trévor, My life with the illness is its first step.

Three ways to contribute, starting today

Give your opinion

Five minutes, anonymous. Patients, relatives, clinicians.

Answer the survey

Test ahead of release

Early access to new features, confidentiality agreement signed in Trévor.

Join the test programme

Take part in the pilot study

The TREVOR-PILOTE pilot study lasts eight weeks; the waiting list is open.

Read the information sheet

The publications behind Trévor.

The published work behind every feature, so you can check for yourself.

Scientific publications

  1. Piel FB, Rees DC, DeBaun MR, Nnodu O, Ranque B, Thompson AA, et al. (incl. Issom DZ). Defining global strategies to improve outcomes in sickle cell disease: a Lancet Haematology Commission. Lancet Haematol 2023;10(8):e633-e686. doi:10.1016/S2352-3026(23)00096-0
  2. Issom DZ, Hardy-Dessources MD, Romana M, Hartvigsen G, Lovis C. Toward a conversational agent to support the self-management of adults and young adults with sickle cell disease: usability and usefulness study. Frontiers in Digital Health 2021;3:600333. doi:10.3389/fdgth.2021.600333
  3. Issom DZ, Henriksen A, Woldaregay AZ, Rochat J, Lovis C, Hartvigsen G. Factors influencing motivation and engagement in mobile health among patients with sickle cell disease in low-prevalence, high-income countries: qualitative exploration of patient requirements. JMIR Human Factors 2020;7(1):e14599. doi:10.2196/14599
  4. Issom DZ, Rochat J, Hartvigsen G, Lovis C. Preliminary evaluation of a mHealth coaching conversational artificial intelligence for the self-care management of people with sickle-cell disease. Studies in Health Technology and Informatics 2020;270:1361-1362. doi:10.3233/SHTI200442
  5. Issom DZ, Zosso A, Ehrler F, Wipfli R, Lovis C, Koch S. Exploring the challenges and opportunities of eHealth tools for patients with sickle cell disease. Studies in Health Technology and Informatics 2015;216:898.

493 citations, h-index 9 (Google Scholar, September 2026) · PubMed · Google Scholar

See all publications, by theme
Sickle cell disease and digital self-management (9)
  1. Piel FB, Rees DC, DeBaun MR, et al. (incl. Issom DZ). Defining global strategies to improve outcomes in sickle cell disease: a Lancet Haematology Commission. Lancet Haematol 2023;10(8):e633-e686. doi:10.1016/S2352-3026(23)00096-0
  2. Issom DZ. Digital health interventions to empower people with sickle cell disease: toward patient-led design. In Sickle Cell Disease, IntechOpen, 2022.
  3. Issom DZ, Hardy-Dessources MD, Romana M, Hartvigsen G, Lovis C. Toward a conversational agent to support the self-management of adults and young adults with sickle cell disease: usability and usefulness study. Frontiers in Digital Health 2021;3:600333. doi:10.3389/fdgth.2021.600333
  4. Issom DZ, Henriksen A, Woldaregay AZ, Rochat J, Lovis C, Hartvigsen G. Factors influencing motivation and engagement in mobile health among patients with sickle cell disease in low-prevalence, high-income countries. JMIR Human Factors 2020;7(1):e14599. doi:10.2196/14599
  5. Issom DZ, Rochat J, Hartvigsen G, Lovis C. Preliminary evaluation of a mHealth coaching conversational artificial intelligence for the self-care management of people with sickle-cell disease. Stud Health Technol Inform 2020;270:1361-1362. doi:10.3233/SHTI200442
  6. Issom DZ, Kanter J. Mind over matter: one person's journey from patient to change-maker. The Hematologist 2018;15(5).
  7. Issom DZ, Hartvigsen G, Bonacina S, Koch S, Lovis C. User-centric eHealth tool to address the psychosocial effects of sickle cell disease. Stud Health Technol Inform 2016;225:627-628.
  8. Issom DZ, et al. Meeting sickle cell patients' unmet needs with eHealth tools: a preliminary study. Scandinavian Conference on Health Informatics, 2015.
  9. Issom DZ, Zosso A, Ehrler F, Wipfli R, Lovis C, Koch S. Exploring the challenges and opportunities of eHealth tools for patients with sickle cell disease. Stud Health Technol Inform 2015;216:898.
Engagement, personal data and mobile health (6)
  1. Woldaregay AZ, Issom DZ, Henriksen A, et al. Motivational factors for user engagement with mHealth apps. Stud Health Technol Inform 2018;249:151-157.
  2. Woldaregay AZ, Henriksen A, Issom DZ, et al. User expectations and willingness to share self-collected health data. Stud Health Technol Inform 2020;270:894-898. doi:10.3233/SHTI200290
  3. Bradway M, Woldaregay AZ, Issom DZ, et al. mHealth: where is the potential for aiding informal caregivers? Stud Health Technol Inform 2021;281:885-890. doi:10.3233/SHTI210306
  4. Henriksen A, Issom DZ, Woldaregay AZ, et al. Dataset of motivational factors for using mobile health applications and systems. Data in Brief 2023;50:109589. doi:10.1016/j.dib.2023.109589
  5. Rochat J, Gaudet-Blavignac C, Del Zotto M, et al. (incl. Issom D). Citizens' participation in health and scientific research in Switzerland. Stud Health Technol Inform 2020;270:1098-1102. doi:10.3233/SHTI200332
  6. Issom DZ, et al. Mobile applications for people with diabetes published between 2010 and 2015. Diabetes Management 2015;5(6).
Public health and non-communicable diseases (2)
  1. Sureshkumar S, Mwangi KJ, Gathecha G, et al. (incl. Issom D). Exploring key-stakeholder perceptions on non-communicable disease care during the COVID-19 pandemic in Kenya. Pan Afr Med J 2023;44:153. doi:10.11604/pamj.2023.44.153.38616
  2. Sureshkumar S, Mustapha F, Yusoff H, et al. (incl. Issom D). An online survey of the perceptions of clinical and non-clinical professionals on healthcare for non-communicable diseases and COVID-19 measures during the pandemic in Malaysia. Int J Public Health 2023;68:1605861. doi:10.3389/ijph.2023.1605861
Hospital medical informatics and the transfusion chain (5)
  1. Albadri R, Perelli I, Freitas F, Waldvogel S, Issom DZ. Designing an interoperable intelligent agent for the blood transfusion chain in Geneva, Switzerland. Stud Health Technol Inform 2026;336:428-432. doi:10.3233/SHTI260191
  2. Bouzo Cueva J, Perelli I, Freitas F, Waldvogel S, Issom DZ. Designing a digital twin for equitable blood donation logistics in Geneva. Stud Health Technol Inform 2026;336:1795-1796. doi:10.3233/SHTI260538
  3. Lovis C, Gaudet-Blavignac C, Chevrier R, Robert A, Issom D, Foufi V. Big data, intelligence artificielle et blockchain pour les nuls. Rev Med Suisse 2018;14(617):1559-1563.
  4. Issom DZ, Hagry C, Wodia Mendo L, Seng H, Ehrler F, Lovis C. Challenges and issues of geolocation in clinical environment. Stud Health Technol Inform 2012;180:447-451.
  5. Ehrler F, Issom D, Lovis C. Technological choices for mobile clinical applications. Stud Health Technol Inform 2011;169:83-87.

Awards and media

2021

Dalle Molle Foundation “Quality of Life” award
Trevor, the sickle cell coach, distinguished in the Dalle Molle Foundation's 2021 quality-of-life competition.

2021

“The Trevor project awarded”, Geneva University Hospitals
HUG institutional news on the award and the project.

2023

Planète Santé, interview, 1 March 2023
“Innovations must take the world as it is into account”, by Laetitia Grimaldi.

2025

Pulsations, the HUG magazine, April 2025
“I always wanted to understand my disease”, by Geneviève Ruiz.

2026

RTS, CQFD, 23 June 2026
“Sickle cell disease: living with a genetic blood disorder”, with Dr Lara Chavaz.

Programmes and training.

Programmes led by expert patients and haematologists, for people living with the disease, their relatives, care teams and future expert patients. Every enrolment goes to the Trévor project and, through it, funds the assistant's development, its free access for patients, the remuneration of expert patients and the clinical evaluation.

One hour with an expert patient, when you need it

You leave with a concrete plan for your goal, written with someone who lives with the disease, and the option to continue in Trévor between sessions.

See how the programme runs

A one-hour session by video call or phone, around a goal you choose: preventing crises, preparing a consultation, managing pain, fatigue, work or studies. Free for participants in the study or the Trévor test programme, half price for members of the Swiss Sickle Cell Association, full hourly rate otherwise.

0 to 110 CHF per hour
Enrol

Fewer crises, with a plan that fits you

In six weeks, you leave with your own prevention strategy, your triggers identified and your reflexes for pain, built with an expert patient who lives with the disease.

See how the programme runs

You meet your expert patient for six 45-minute video sessions. Each session is prepared, then summarised in writing, and your goals are tracked in Trévor between sessions. A haematologist supervises the whole programme.

890 CHF
Enrol

Understand the disease to decide with your doctors

By the end of the programme, you can explain your disease, anticipate a crisis, prepare a consultation and defend your rights, surrounded by a group that stays in touch afterwards.

See how the programme runs

The programme runs over eight weeks, with one module per week and a live workshop with an expert patient and a haematologist. A private discussion group supports your progress, and a certificate concludes the course.

490 CHF
Enrol

Manage sickle cell disease with confidence

Your team recognises acute chest syndrome, treats pain according to guidelines on arrival, supports the paediatric-to-adult transition and knows which digital tools to offer.

See how the programme runs

The training takes place over one day, in your unit. The programme alternates clinical cases, applied pathophysiology and motivational interviewing, and concludes with a continuing education certificate. Participation costs 590 CHF per person, or 3 900 CHF for a team of up to ten people.

from 590 CHF
Enrol

Turn your experience into a paid skill

You run workshops and support other patients within Coach Drépano programmes and partner centres, paid for each session.

See how the programme runs

The training comprises forty hours spread over three months, followed by a supervised facilitation placement within the Coach Drépano programmes. It concludes with the Coach Drépano expert patient certificate.

2 400 CHF
Enrol

Solidarity rate of 50% for members of the Swiss Sickle Cell Association without income or on disability insurance, on request. Payment in three interest-free instalments by bank transfer.

DrépaNews, today's watch.

Science of the day, protocol changes, medicines, care, and what is new in Trévor and Coach Drépano.

What's new in TrévorNew

DrépaNews comes to Trévor and coachdrepa.no

A worldwide sickle cell watch, updated every day: science of the day, protocol changes, medicines, care, and what is new in Trévor and Coach Drépano. In the bot: More, then DrépaNews, or the /news command.

17.09.2026 · Trévor

What's new in TrévorNew

Emergency care card: readable in ten seconds by a clinician

Precautions (allergies, contraindications, venous access, home oxygen) placed right under the banner, FR and EN keyword summaries, care-team recommendations in both languages, Coach Drépano, HUG, CHUV and Association Suisse Drépano logos. Command /carte.

17.09.2026 · Trévor

What's new in TrévorNew

Trévor test programme: the test agreement unlocks full access

Everyone reads the information sheet in the chat, section by section, then signs the test agreement. The daily check takes ten seconds to one minute, watches and rings connect by brand with a guide, and a human coaching session is booked by e-mail from the bot or the website.

16.09.2026 · Trévor

Coach DrépanoNew

Coach Drépano coaching sessions: free in the study, ASD member rate

A one-to-one coaching session with an expert patient can be booked on coachdrepa.no: free for people enrolled in the study, reduced rate for Association Suisse Drépano members, full hourly rate otherwise. The TREVOR-PILOTE pilot study waiting list remains open.

15.09.2026 · Coach Drépano

Protocols and guidelinesGuideline

Oxygen in the emergency department: only when saturation drops

US guidelines (NHLBI expert panel report, 2014) reserve oxygen for crises with SpO₂ below 95% or below the person's usual value; routine oxygen during an uncomplicated painful crisis has no demonstrated benefit. Your usual value is on your care card: show it on arrival.

14.09.2026 · NHLBI 2014

CareLow evidence

Hyperbaric chamber during a crisis: encouraging signals, a randomised trial under way

A French series of nine patients (15 sessions) observed a rapid drop in pain (mean score from 3.3 to 1.9 within 24 h) and in morphine use. The level of evidence remains low: small series, heterogeneous protocols. A multicentre double-blind randomised trial (HBOT-SCD, patients aged 8 and over) is under way to settle the question. Discuss it with your haematologist, without changing your current care.

13.09.2026 · PubMed 22828815 ; PubMed 39613437

Follow DrépaNews in Trévor

The community's daily meeting point.

Every day on @coachdrepano, a sourced scientific fact, a habit to apply the same day and an answer to a community question. The six latest posts, live.

See the latest posts

Follow @coachdrepano

A team that knows the disease from the inside.

“Since I was very young, I wanted to understand my disease and I took an active part in my treatments.”

Prof. David-Z. Issom, in Pulsations, the HUG magazine, April 2025.

A word from the founder

I owe my life to the blood transfusions (red cell exchanges) I receive every five to seven weeks. Then, at the end of 2023, blood compatible with my phenotype ran out for six months.

My body gave way, a major crisis broke out and I came close to dying, so this project stopped with me for two and a half years.

Today I write these lines first thanks to anonymous blood donors, who gave their blood at the moment it became vital, then thanks to the teams of the Geneva University Hospitals, from the hyperbaric chamber to haematology, through anaesthesia, internal medicine and intermediate care, who held on with me to the end.

The rest I owe to a long habit of understanding my disease and to unshakeable stubbornness. To each and every one of you, thank you. Now Coach Drépano is back with energy.

Dr. David-Z. Issom, patient researcher, professor of applied sciences and founder of Coach Drépano.
Give blood in Switzerland →

Content funded by foundations and public institutions, independently of the pharmaceutical industry.

Dr David-Z. Issom, Professor of Applied Sciences

Scientific lead

  • Teaches business informatics at HEG-Genève, and global health and medical informatics at the University of Geneva.
  • Medical informatics researcher at the Geneva University Hospitals.
  • PhD in biomedical sciences, global health track (University of Geneva, 2021, summa cum laude).
  • Graduate in medical informatics from the Karolinska Institute (Stockholm).

Commitments

  • Co-president of the Association Suisse Drépano.
  • Founding member of the European Sickle Cell Federation (ESCF).
  • Alternate member of the Geneva cantonal commission for patients' rights (2018-2025).
  • Co-author of the 2023 Lancet Haematology Commission on sickle cell disease.

HUG clinical haematology unit

Medical validation of content, care and emergency cards, teleconsultations.

Swiss Sickle Cell Association

Patient association: it trains expert patients and runs the support programmes.

Academic originBorn from its founder's doctoral thesis in global health at the University of Geneva, developed at the HUG Division of Medical Information Sciences.
Scientific networkEvaluated with patients in the French Caribbean together with Inserm and the CAREST Caribbean network; educational content enriched by RoFSED and the MCGRE rare disease network (France).

A question? A human answer.

david.issom@hug.ch, reply within five working days. A first twenty-minute interview is free, to choose the programme suited to your situation.

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Frequently asked questions.

Is Trévor free?

Yes. Trévor is a research project funded by foundations and public institutions; it remains free for patients and relatives. Support programmes and training courses are paid and fund the time of expert patients and professionals.

Does Trévor replace my haematologist?

Trévor informs, educates and supports daily life; care decisions remain with your medical team. As soon as a warning sign appears, Trévor directs you to your team or the emergency number.

Who answers my questions?

An artificial intelligence (Claude, Anthropic) framed by strict rules and content reviewed by a HUG haematologist and an expert patient. Every answer cites its sources. Expert patients and haematologists take part in the programmes and teleconsultations.

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Where is my data and who can access it?

Your data is hosted in Switzerland (Infomaniak, Geneva data centre, ISO 27001 certified), encrypted in transit and at rest, backed up every night in encrypted form. Only you access it, along with the clinicians you explicitly authorise. Technical logs contain counts only; the text of your messages stays out of the logs.

Can I view, export or delete my data?

Yes, at any time from Trévor's “🔐 My data” menu, to view, export as CSV, JSON or FHIR, or delete everything in one tap. An email to david.issom@hug.ch achieves the same result.

How do I enrol in a programme and pay?

The “Enrol” button opens the enrolment page (two minutes). Payment is made online by card or TWINT, or by bank transfer to HES-SO Genève with the reference “Projet Trevor”. Funds are received by HES-SO Genève and allocated to the project; they finance development, hosting and testing with partner centres. Payment in three interest-free instalments by bank transfer, a 50% solidarity rate for members of the Swiss Sickle Cell Association without income or on disability insurance, and a full refund if you withdraw after the free interview.

How can I contribute to research right now?

Three paths are open to you. The anonymous interest survey (five minutes, on the web or in Trévor with /enquete), the test programme under a confidentiality agreement (/beta in Trévor, immediate access to features in development), and the waiting list for the TREVOR-PILOTE pilot study, whose recruitment opens upon authorisation by the Geneva Cantonal Research Ethics Commission.

Is the test programme a clinical study?

The test programme falls under service improvement and data protection law. The agreement is signed in Trévor, data is processed with your consent and experimental features are shown for information only. The pilot study, by contrast, is human research submitted to the ethics commission; it starts after authorisation.

Which smartwatch or smart ring works with Trévor?

Oura and Fitbit connect directly; Samsung Health, Apple Health and Google Fit through a file export. Trévor displays your measurements and, if you enable it, an estimate of your 48-hour crisis risk. This estimate is a beta feature at the research stage, with no clinical validation to date; it is shown for information only, never as a diagnosis, and every care decision remains your medical team's. You enable it after reading a notice in Trévor and can disable it at any time.

Does Trévor cover diseases other than sickle cell disease?

Yes. Trévor currently offers dedicated profiles for sickle cell disease, thalassaemia, Ehlers-Danlos syndrome and malaria, with questionnaires, warning signs and an emergency card specific to each disease, plus an open profile for any other rare or neglected disease. For malaria, health professionals have a guided protocol based on WHO guidelines.

Does Trévor work outside Switzerland?

Yes, wherever Telegram works, in ten languages (French, English, German, Italian, Spanish, Portuguese, Arabic, Lingala, Swahili, Hindi). The emergency numbers shown adapt to the country set in your profile.

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