How are the parameters from the Blood Pressure module calculated?

The formulas used to calculate each parameter available in the Blood Pressure add-on for LabChart can be found in LabChart's help documentation under Blood Pressure > Blood Pressure Parameters. The list of parameters and their calculation methods are below:

Ventricular Parameters

· Max Pressure: The maximum pressure during the
cycle.
· Min Pressure: The minimum pressure during the
cycle.
· Mean Pressure: The arithmetic mean pressure in the
current cycle.
· Max-Min Pressure: The difference between minimum and
maximum pressures.
· Heart Rate: Calculated as 60 / (Cycle
Duration).
· Max dP/dt: The steepest slope during the upstroke of the
pressure curve.
· Min dP/dt: The steepest slope during the downstroke of
the pressure curve.
· EDP: Pressure at the end of diastole.
· Systolic Duration: Elapsed time between the start of the
cycle (at EDP) and the time of Min dP/dt.
· Diastolic Duration: Elapsed time between the time of Min
dP/dt and the end of the cycle.
· Cycle Duration: Elapsed time between two alignment
points.
· Tau: The exponential time
constant of relaxation.
· Pressure Time Index: Also known as tension–time index.
The average ventricular pressure during systole, multiplied by the systolic
duration.
· Contractility Index: Max dP/dt divided by the pressure
(P) at the time of Max dP/dt.
· IRP Average dP/dt: The slope of a straight line fitted to
the pressure over the Isovolumic Relaxation Period used for estimation of
tau.

Arterial Parameters

· Systolic Pressure: The maximum pressure during the
cycle.
· Diastolic Pressure: The pressure at the start of the
cycle.
· Dicrotic Notch Pressure: Pressure at the time of the
dicrotic notch (if detected).
· Mean Pressure: The arithmetic mean pressure in the
current cycle.
· Pulse Pressure: The difference between diastolic and
systolic.
· Ejection Duration: Elapsed time between the start of
cycle and the dicrotic notch (if
detected).
· Non-Ejection Duration: Elapsed time between the dicrotic
notch (if detected) and the end of cycle.
· Cycle Duration: Elapsed time between two alignment
points.
· Heart Rate: 60 / (Cycle
Duration).
· Time to Peak: Elapsed time between the start of the cycle
and time of systolic pressure.
· Mean Diastolic Pressure: The average pressure between the
dicrotic notch (if detected) and the end of cycle.