Time from a vasopressor bolus to the pressure response¶

How quickly arterial pressure responds to a phenylephrine or ephedrine bolus, with the charted dose times' rounding taken into account. Not feasible in VitalDB, which records bolus totals but no bolus times; kept for a dataset that does.


Side	both
Status	planned
Variables	Anaesthesia record events, Arterial pressure (SNUADC)
Studies	Drug effects as a clock check, Anaesthesia record times are rounded up, Bolus drugs as unit-dose counts

The question¶

How long after a bolus does arterial pressure start to rise?

Inputs¶

Each input links to its measurement page: how it is timed, how its value was recorded, and how uncertain both are.

Input	Unit	What it is
Anaesthesia record events		Anaesthesia and operation start and end times in the clinical table. Anaesthesia start marks the start of anaesthesia care, a median 14 minutes before device-marked induction (Post-induction hypotension, from the charted start and from the devices).
Arterial pressure (SNUADC)	mmHg	Invasive arterial pressure, sampled by SNUADC at 500 Hz from the monitor's analogue output.

Why the atlas changes the answer¶

Charted drug times are rounded, and the rounding is wider than the response latency.

Takeaways¶

Planned, but not feasible in this release: the clinical table holds each drug's bolus total per case, and no bolus has a time (Bolus drugs as unit-dose counts); the event track holds only the case and operation times (The EVENT track repeats the clinical table). Kept as a pointer for a dataset that records bolus times.

Studies it relies on¶

Study	Date	Status	Summary
Drug effects as a clock check	2026-10-13	current	Infusion pumps, the rapid infuser and the cerebral oximeter share no waveform with the reference. Drug effects that follow infusions at plausible delays (propofol to BIS in about 2 minutes, fluid to CVP in about 30 s) bound their clocks to well within a minute of the recorder.
Bolus drugs as unit-dose counts	2026-10-13	current	Most bolus drug totals are exact counts of standard doses, not rounded estimates; propofol is the exception, and zeros are ambiguous.
Anaesthesia record times are rounded up	2026-10-12	current	Anaesthesia start and end entered on a 5-minute mark sit 90–290 s later, against device markers, than entries typed to the minute. Rounding up to the next 5 minutes fits every one of 11 markers better than rounding to the nearest or down.