Ipump Pain Management System Operator’s Manual
9-7
CD07-19-E4-766
How Trumpet Graphs are Interpreted
The Trumpet Curve graph (Figure 9-2) provides a graphical view of the maximum deviation in flow rate from
the programmed delivery rate for specific segments of delivery time. The horizontal axis does not represent
elapsed delivery time, but rather acts as a graphical reference for selecting specific observation time intervals.
The widest area of the trumpet curve (greatest deviation) reflects the smallest sampling intervals or
observation windows. As the sizes of the sampling intervals increase (in minutes), the deviations in flow
from the programmed delivery rate are reduced as the deviations are spread out over the longer periods of
time. This results in the narrowing of the trumpet curve giving a more realistic representation of the device’s
average flow rate accuracy over longer intervals of time.
For example, if you were to look at the maximum and minimum percentage error points corresponding to the
60-minute interval point on the Observation Interval axis, you would be looking at the average flow variance
for any 60-minute period throughout the infusion.
Oct02_0719E4766.book Page 7 Friday, August 3, 2007 1:46 PM