GE CARESCAPE - How to interpret the NMT values

Neuromusculartransmission
ElectroSensorandelectromyography(EMG)
MeasurementwithElectroSensorisbasedonelectromyography.Threeelectrodesare
placedonthemuscle,andtheinnervatingnerveisstimulated.Therecordedelectrical
activityofthemuscleisinverselyproportionaltothedegreeofblock.
Stimulationmodes
●Trainoffour,TOF:Recommendedformostcases.Itisalsothedefaultsetting.
●Doubleburststimulation,DBS:UsefulwhenusingtheMechanoSensor.Itenables
bettervisualobservationofthefadinginresponses.
●Posttetaniccount,PTC:Usedforestimatingtherelaxationlevelwithtetanic
stimulation.
●Singletwitch,ST:Singletwitchmodeispracticalwhenusingdepolarizingrelaxants:
inthesecases,TOF%doesnotgiveanyadditionalinformationaboutthepatient
status.
HowtointerprettheNMTvalues
Whenneuromuscularblockdeepens,differentstimulationmodesmaybeneededto
assesstherelaxationstatus.Thefollowingtabledescribesthedepthofrelaxation.
100TOF%20
4
Count010PTC0
Light
RELAXATIONMETER
Deep
Trainoffour(TOF)mode
InTOFstimulusmode,fourstimulationpulsesaregeneratedat0.5secondintervals.
Theresponseismeasuredaftereachstimulusandtheratioofthefourthtotherst
responseoftheTOFsequenceiscalculated,resultinginTOF%.
WiththeElectroSensor,T1%isdisplayed.Ifthereferenceissuccessfullyfound,ascale
isalsoincluded.Scalemarkersrepresent0%,25%,50%,75%and100%reference
values.Whennoreferenceisavailable,noT1%valueisdisplayedandthebarsare
notscaled.
Whenrelaxationdeepens,theTOF%declinesuntilthefourthresponsedisappearsand
noTOF%isavailable.Thedegreeofneuromuscularblockisthenestimatedfromthe
numberofresponses,thecount,whichrepresentsthenumberofresponsesdetected
tothefourstimuli.Thefewertheresponses,thedeepertherelaxation.
Numberofresponses,countNeuromuscularblockMusclepower(%ofcontrol)
195%5%
290%10%
3
85%15%
4
75%25%
Doubleburststimulation(DBS)mode
DBSconsistsoftwoseparatebursts.Eachburstconsistsofthreeconsecutivepulses
ata50Hzfrequency.Theresponseratioofthesecondtotherstburstiscalculated,
resultinginDBS%(equivalenttoTOF%).
2062971-001CARESCAPEModularMonitors369