Concept explainer
The ordered snapshot
Explains the snapshot taken when an order is placed, which preserves the catalogue detail and instructions as they stood at that moment.
When you place an order, Pensieve freezes a snapshot of the catalogue item exactly as it stood. The snapshot preserves the ordered detail and the instructions at that moment, so a later change to the catalogue leaves your placed order unchanged.
What the snapshot holds
The snapshot is a frozen copy of the catalogue item and the detail you added, taken the moment you place the order. It carries enough to describe the order in full on its own.
The kind of item ordered, such as medication or imaging.
The standard clinical code for the item.
The display name and short name as they read at placement.
The ordered detail: dose, route and schedule for a medicine; specimen for a test; modality and body part for a study.
The special instructions you added when you placed the order.
A plain one-line description of the order.
Why the order freezes it
The catalogue is a living list. An administrator renames an item, adjusts its routing or retires it as the hospital changes. A placed order records a clinical decision made at a point in time, so it holds its own copy of the item rather than reading the live catalogue each time it is opened.
Forge writes the snapshot once, at placement, and leaves it fixed for the life of the order. A later catalogue change describes the item as it is today, while the snapshot describes the item as it stood when the decision was made.
Reading an order anywhere
A patient's orders travel with the record across sites. A reader at another site renders the order entirely from its snapshot, so an order placed at one site reads the same everywhere, independent of that site's own catalogue.
What was first ordered, and what is ordered now
The snapshot is the record of what was first ordered. A later correction, such as a dose adjustment or a change of route, is recorded against the order as a new version, and each earlier version is kept. The snapshot stays as the original, and the order carries its current values beside it.
A changed order says so
When a reader at another site opens an order that has been changed at the ordering site, the order shows plainly that it was modified and that the values on screen are the ones first ordered. The reader sees the original clearly marked, rather than a changed value with no sign that it moved.
Common questions
Does renaming a catalogue item change past orders?
A rename describes the item from then on. Every order placed before the change keeps the name and detail it was placed with.
Why keep a copy on every order?
The copy makes each order a complete record of the decision, readable on its own and identical across sites.
Can I still correct a placed order?
Yes. A correction is recorded as a new version with its history kept, and the snapshot holds what was first ordered.
Read how a patient's record and its orders travel between sites in the record across sites.