Piloting with one surgical team in Lima
Not another app. The team's logbook.
Type what happened in WhatsApp. rzero files it on the right case, confirms it by name, and at month end the log is already written — in the team's own words, in order.
- Nothing to install
- No signup, no password
- No patient identity
The product
It all happens in the conversation.
A colleague adds you by phone number and you start typing. No forms, no fields, no menus: rzero tells a note from a question — and when it isn't sure, it asks.
rzero
team log
Carlos, between two operations
rzero speaks Spanish. Conversations are shown here in English.
Why rzero
Taking notes on WhatsApp isn't the new part.
The new part is that every note lands on the right case, is confirmed by name, and is kept exactly as written.
Always the right case
Every confirmation names the case and the time. When it's unclear which case a note belongs to, rzero asks. It never switches case on its own.
Your words, verbatim
Stored exactly as you typed it, shorthand and all. Never rewritten, never “cleaned up.” And it learns how you write: hb, qx, eco.
The report writes itself
Weekly, monthly or by dates. Every number traces back to the entries behind it; a number that can't be traced isn't shown.
Before and after
Today the log gets rebuilt. With rzero, it's written as it happens.
Today
- At month end, the lead surgeon rebuilds each case's log from memory and scattered messages.
- Getting onto a colleague's case means a phone call at 11 pm.
- Someone who joins a case halfway has no single place to catch up.
- Notes live across chats, paper and everyone's memory.
With rzero
- The monthly report is generated from what the team wrote:
report for David. - You ask for access in one message,
request access to David, and the lead approves in another. summary of David: the full timeline, in order, with who wrote each entry and when.- One log per case, filling itself as the team works.
How it works
From the operating room to the log, in four steps.
Nothing to install or set up. If you use WhatsApp, you already know how to use rzero.
You're invited by phone number
A colleague on the case adds you. You send your first message and rzero asks your name, once. No app, no signup, no password.
invite +51 987 654 321You pick the case
It stays active for 4 hours or until the day ends, whichever comes first. Yesterday doesn't carry over: the next morning, rzero asks which case you're on.
use case DavidYou type what happened
Between operations, in your own words. The confirmation arrives in under 2 seconds, with the case name and the time.
David11-feb 14:35You get it back when you need it
Ask a question, catch up, or request the report. Every fact comes with who wrote it and when.
summary of David
Reports
The log you rebuild from memory today, already written.
rzero builds the report with code, not guesswork: first what happened, in the team's exact words; then the counts; and, clearly apart, any interpretation.
Facts and interpretation never mix
The timeline is verbatim. The generated summary sits in its own section, labeled as such.
Every number is traceable
Each count points to the entries behind it. A number that can't be traced doesn't get shown.
Reproducible, identically
Each report is saved with the exact list of entries that made it. Generate it again months later and get the same thing.
Conflicts are shown, not resolved
When two notes disagree, both appear under Pending, with author and time. rzero doesn't pick a winner.
TEAM LOG — internal use by the surgical team.
Not an official clinical document. Does not replace the medical record.
Case David · 01–28 feb · 42 entries · 4 authors
What happened
- 09-feb 10:12pre-op evaluation ok, scheduled for the 11th
- 11-feb 14:35surgery uneventful. minimal bleeding, no transfusion. to ward at 16h
- 11-feb 18:20hb 11
- 12-feb 09:30eco control: 3 cm collectioncorrects his entry from 09:24
- 13-feb 08:10hb 9.4, recheck this afternoon
By type
- Note
- 12
- Lab
- 9
- Evaluation
- 6
- Medication
- 5
- Status
- 4
- Imaging
- 3
- Other
- 2
- Surgery
- 1
Each count links to its entries.
Interpretation
Generated summary · kept apart from the facts
Pending
12-feb · “no fever” (Carlos, 10:05) and “38.5 °C” (Martha, 12:10) — unconfirmed
Limits
Honest about what it doesn't do.
rzero is the surgical team's internal notebook. It is not a medical record, a clinical tool, telemedicine, or anything a patient touches. That line is part of the product, not a footnote.
No patient identity, ever
Cases are nicknames. No names, ID numbers, birthdates or faces in photos. Who “David” is stays in the team's heads — nothing can leak that was never stored.
Safety questions are refused
Allergies, blood type, anticoagulation, consent, dosing. Refused before anything is looked up, even when an entry mentions it. When in doubt, refused too.
Nothing is edited or deleted
A correction is a new entry pointing at the old one. The original stays, marked as replaced. The trail is always complete.
One case per answer
Isolation between cases is enforced by the database before the model sees anything — not by an instruction. One patient's notes never show up in an answer about another.
The model never writes
The AI reads and proposes; code does the saving. Everything written is logged with author and time, and can be audited.
“No record,” never “no”
rzero never claims something didn't happen. Only that nobody wrote it here.
Before the first real case, the practice signs an agreement covering purpose, retention period and data deletion.
How it talks
Brief, precise, and never guessing.
rzero sounds like the most dependable member of the team: the one who writes everything down, reads it back with the case name, and never fills a gap with a guess.
Illustrative examples. All bot copy is reviewed by a surgeon before it reaches the pilot.
The name and the mark
Why rzero?
- R0
- (R-zero) a complete resection, with clear margins.
In surgical oncology, R0 is the result you aim for: nothing left behind, and clean margins.
It's what we aim for in every case's log. Complete, because nothing the team wrote is lost or rewritten. And clean margins, because one case never touches another.
The mark is a pocket logbook whose smile is the ✓ — the moment rzero confirms a note.
Where we are
The road to the pilot.
We're building rzero in stages, and each one has to earn the next. First we prove the team wants the output; then we build the machine that makes it.
- v0.1
Concierge
No code. We produce one team's weekly log by hand and measure how long it takes them today. If they don't ask for it again, we stop.
- v0.2
Capture
Invitations, nicknamed cases, the active case, and notes confirmed with the case name.
- v0.3
Recall
Questions with citations, the safety guard, and corrections.
- v0.4
Reports & closure
Catch-up summaries, weekly and monthly reports, photos, and closing cases.
- v1.0
Pilot
One real team, a real WhatsApp number, and a signed agreement with the practice.
Minutes to produce the monthly log, against the baseline measured before rzero.
Do I have to install anything?
No. rzero lives in WhatsApp. A colleague on the case adds you by phone number and you message it like any other contact. No app, no signup, no password.
Is rzero a medical record?
No. It's the surgical team's internal log: notes between physicians. It doesn't replace the medical record, it isn't a clinical tool or telemedicine, and no patient ever uses it. Every report says so in its header, and that header can't be removed.
What patient data does it store?
Nothing that identifies them. Cases are named with nicknames: no names, ID numbers, birthdates, contacts or faces in photos. If a nickname looks like a real name or an ID number, rzero reminds you.
What if I write to the wrong case?
You see it immediately, because every confirmation names the case. To prevent it, rzero asks before saving when you mention another case, and asks first when no case is active. If it still happens, correct my last message adds the correction.
Can I delete or edit a note?
No. Nothing is edited or deleted: a correction is a new entry pointing at the old one, and only the author can correct their own entry. Reports show the corrected version and note who corrected it and when.
Does it answer clinical questions?
It answers what the team wrote, with author and date. It doesn't conclude or recommend, and it refuses safety questions (allergies, blood type, anticoagulation, consent, dosing) even when it holds the answer.
Who can see a case's notes?
Only the people on the case. To join, you send request access to David and the lead surgeon approves or rejects. To anyone not on the case, rzero won't even confirm the case exists.
Does it work in WhatsApp groups?
No. Everyone talks to rzero one-to-one; what's shared is the case's log.
Can I send photos or voice notes?
Photos yes, with a one-line description, as long as they don't identify the patient: no faces, wristbands or chart headers. Voice notes aren't in the first version.
How is the data protected?
Mainly by not holding identity: nothing can leak that was never there. On top of that, everything is encrypted in transit and at rest, and note text never appears in application logs. Before the first real case, the practice signs an agreement on purpose, retention and deletion.
When can I use it?
We're setting up the pilot with one surgical team in Lima. If you're interested, write to us and let's talk.
Your next monthly log, already written.
We're setting up the pilot with one surgical team in Lima. If you lead cases and rebuild the log from memory today, let's talk.
or email us at [email protected]