Bedfont NoxBox - Monitoring System

42
6.2 Monitoring System
WARNING: The sample stream ow rate is set to 225 ml/min. Check
the trigger sensitivity of a ventilator in synchronized mode when using
the NOxBOX
i
system to ensure that it is not being tripped by the
sample stream ow.
NOTICE: For patients on very low tidal volumes it may be necessary
to increase the bias ow to reduce the effective leak created by the
NOxBOX
i
sample rate. For example, increasing bias ow from 2 L/min
to 8 L/min can reduce apparent leak from 78% to 20%, and effectively
reduce risk of NO
2
build-up.
AsamplepointislocatedclosetothepatientY-piece,whichtakesasmallsamplefromthe
deliveredinhalantgasmixture,pulledatasteadyratebytheinternalsamplepump.
Thesamplegasisconditionedbypassingthroughawatertraptoremovecondensateanda
dryingtubetoachievecorrecthumidity,beforepassingacrossthethreegassensorswherethe
sample is analysed for the three
constituentgasesofinterestNO,NO
2
and O
2
.
Anelectronicallycontrolledvalvewithinthesamplecircuitcanbeswitchedtoperformanautomat-
ic zero-calibration function. This allows the monitor to take a baseline reading of clean air to check
and correct for sensor drift.
6.3 Touch Screen Interface
6.3.1 Brief Navigation Guide
TheservicekeyenablestheServiceEngineerlog-in.
Press Next to proceed to next screen.
PressBacktoreturntothepreviousscreen.
Presstoacceptorconrmthestatementon-screen
Press to decline or deny the statement on-screen
Greyed out buttons indicate that they are temporarily disabled. An action or
testmustbeperformedorcompletedtoactivate.
6.3.2 On-screen User Guide
The NOxBOX
i
hasanintegratedQuickStartGuide(QSG)thatdisplaysstep-by-stepinstructions
on-screen.