Title:ANon‐InterchangeableConnectorforCentralVenousPressureLines

Contact:PeterJYoungMDFFICMFRCADAMBChB(Peteryoung101@gmail.com)

Abstract

Theunintentionalperipheraladministrationofotherirritantandvasoconstrictordrugsor

parenteralnutritionsolutionsiscommon.Itcausesphlebitisandtissuenecrosisandmayevenbe

fatal.Thepreventionoftheincorrectconnectionofinfusionsintendedforcentralvenous

administrationrequiresanengineeredsolution.Theintroductionofuniqueconnectorsthat

preventmisconnectionofneuraxialandgastricfeedinglinesdonotandcannotaddressthis

problemasthereisanabsoluterequirementtobeabletoconnectastandardluersyringetothe

centralline.Allperipheralinfusionsandinjectionscansafelybegivenintoacentralcatheter,

however,thecentrallineinfusionsetshouldnotbeabletoconnectwithastandardfemaleluer.

Introduction

TheNHShasidentifiedtheincorrectadministrationofconcentratedpotassiumsolutionsasa

“NeverEvent.”1Despiterigorouscheckingproceduresandmultiplesystemssolutions,theseerrors

continuetooccur.2Thiserroroccursbecausethereisnoengineeredsolutionpreventingthe

misconnectionofadrugintendedforcentraldeliverytoaperipheralcannula.Theluerconnection

isubiquitoustoallintra‐venousdeviceswhatevertheirroute.

In2006,JCAHOissuedanalerthighlightingthedangersoftubingmisconnections.3Similar

problemshavebeenidentifiedintheNHSandotherhealthservicesacrossEurope.Inadvertent

connectionsofinfusionsintendedforthecentralvenouscatheter(CVC)totheperipheralcannula

(PC)arepossiblebecausebothcarryidenticalluerconnectors.Thiserrorrisksboththrombo‐

phlebitisandtissuenecrosiswhichmaybeextensive,evenrequiringsurgery.4

Unlikeotherroutes(nasogastricandneuraxial),itisnotpossibletointroduceatotallyunique

connectorforcentralsystemsasthereisarequirementforthecentralsystemtoacceptstandard

luerinfusionsetsandluersyringes.Thisisnecessarytoenabletheadministrationofemergency

drugsinatimelywayandtoallowthecentraladministrationofthosenon‐irritantdrugswhichcan

begivenbothcentrallyandperipherally.Alldrugsthatcanbedeliveredperipherallyaresafefor

administrationintoCVC

Wepresentarisk‐free,seamlesssolutiontothisproblem–theNon‐InterchangeableConnector

System.Twomodificationsarerequired.Firstly,theCVcatheterfemaleluerconnectorwouldbe

alteredinsuchawaythatitwouldacceptboththeconventionalluersyringesandinfusionlines

(seefigure1)andalsoanewmalenon‐interchangeableconnector(NICS)onlinesthatareintended

onlyforcentraldelivery(seefigure2).ThemaleNICSlocatedonaCVinfusionlinewouldnot

connecttotheluerconnectoronaPC.

TheNICSCVChasaNICSfemaleconnectorwith4projections,eachwithacircumferential

dimensionequaltothatonthelipofthestandardluerconnectors.Thisallowsittoconnecttoboth

standardluerandNICSinfusionlinesandsyringes.TheNICSCVinfusionlinehasamaleNICS

connectorwithacorrespondingdiscwithakeystructureallowingtheengagementofthe4

projectionsoftheNICSCVcatheterbutthisdiscwouldpreventengagementwiththestandard

femaleluerconnectoronaperipheralcannula.

ThefemaleNICSconnectorontheCVcatheterstillallowsaccesswithstandardsyringes/infusion

linesallowingseamlessandsafeintroductionoftheNICSsystem.

WehavecarriedoutastudyoftheuseoftheprototypeNICSinourhospitalaimingtoprovethat

theNICSwouldpreventcentraltoperipheralmisconnectionandthatitallowstheconnectionof

standardluerinfusionsandsyringestotheCVC.

TheprimaryoutcomemeasurewastheabilitytoconnectNICSinfusiontoNICCVCbutnottoaPC

andtheabilitytoconnectstandardluerinfusiontobothPCandNICCVC.

Wealsousedavisualanaloguescale(VAS)andmeasuredthetimetakenforconnectionofNIC‐NIC

versusstandardluer–PC.

Methods:

Clinicians(n=66)weretimedmakingNICandstandardluerconnectionsandwereaskedto

completeaquestionnairewithavisualanaloguescale(VAS)foreaseofuseofthestandardluerand

NICSconnectors.

Results:

Connectionsuccessresultsarepresentedintable1.Allconnectionswerepossibleexceptno‐one

wasabletoconnectthemaleNICStoafemaleluer.

ThemeanVASfortheluerconnectorwas0.34cmof10cmcomparedwith1.13cmof10cmforthe

NICS.Themeantimetoconnecttheluer‐lockwas1.22secondscomparedwith1.7secondsforthe

NICS.Whilststatisticallysignificant,thisdifferenceisclinicallyirrelevant.

NICFemaleConnector

(NICCVcatheterconnector)

StandardLuerfemale

connector

(PCconnector)

NICMaleConnector

(NICCVinfusionset)

66(100%)

0(0%)

StandardLuerMaleconnector

(Standardinfusionorsyringe)

66(100%)

66(100%)

Table1:AbilitytoconnectNICSandLuerconnectors

Conclusions

Errorsintherouteofadministrationofirritantandvasoconstrictordrugscontinuetocause

avoidablepatientinjuryinhospitalpractice.Totalparenteralnutritionisfrequentlygiveninthe

wardenvironmentandmustnotbeconnectedtoanythingbutacentralvenousline.Thesepatients

commonlyhavebothaCVcatheterandaperipheralcatheterinplaceandsoerrorscananddo

occur.Atypicalcriticallyillpatienthasamultiplelumencentralvenouscannula,anumberof

peripheralvenouscannulae,anarteriallineandaspinalorepiduralcatheterallwiththeassociated

3‐wayluerconnectors.Commonly,anyonepatientcanhaveover10luerlockconnectionsaround

theirbedspaceallowingaccesstomanydifferentroutes.Itisessentialthatdrugsintendedfor

centrallineadministrationshouldnotbeabletobeconnectedtoanyotherluerconnectoranditis

alsoequallyimportantthatstandardluer(male)connectorinfusionsandsyringesshouldcontinue

tofitonanCVcatheter.Duetothenatureofgeneralhospitalandcriticalcareinterventionslines

arefrequentlydisconnected,replacedorswapped.Anunfortunatelycommonerroristoconnecta

linecontainingfluidthatcanonlybegivensafelythroughacentralvein(e.g.concentrated

potassiumchloride,TPNorvasoconstrictors)toaperipheralcannularesultinginphlebitisor

necrosis.Thisispainfulanddistressingforthepatientandoftenleadstodisciplinaryactionagainst

staffandmaybefatal.

Safetyconsiderations

Itisimportantwhenintroducingnewsystemsthatareintendedtopreventrarecomplicationsinto

ahealthcareenvironmentthatanadditionalriskisnotintroduced.Simplecalculationsindicatethat

therearemanythousandsormillionsofluerconnectorinteractionsforeachepisodeofsignificant

patientharmassociatedwithCVinfusionmisconnection.Anysystemmustthereforeintroducezero

risktoeachofthesenormalconnections.Ideallytheteachingofstaffshouldbeminimalandthey

wouldnotneedanyunderstandingofthesystem.Apreviousstudyof52intensivecarenurses

surveyedfollowingtheintroductionoftheNICairconnector(anon‐indexedNIC)intoclinical

practiceshowedthatalthoughroutinelyusingNICS,nonewereawareofachangeandonlybecame

awareoncetheywereaskedtoattemptamisconnection[MDTEvans].5

ThereareseveralmarketdriversfortheintroductionofaNICsystem.Inadditiontothepatient

safetybenefits,thesewouldpotentiallybenefitbothpharmaceuticalcompaniesaswellasCVC

manufacturers

Firstly,byprovidingconcentratedpotassiumsolutions,TPNandvasoconstrictoragentsinan

infusionsystemwhichendsintheNIC,thedrugcompanieswouldbeabletopreventthe

misadministrationofthesedrugsintoperipheralcannulae.Thiswouldallowdrugmanufacturersto

distributetheirdrugasasaferalternativetoothergenericdrugs.TheNHSNeverEventwouldtruly

becomeanevereventasitwouldnowbeimpossibletomisconnecttheconcentratedpotassium

solutiontoaperipheralcannula.

TherewouldalsobecommercialviabilityforthemanufacturersofCVCandperipherallyinserted

CVClines.ItwouldbepossibletointroducethenewsafeNICCVCwithoutanyneedforretraining

orevenlettingcliniciansknowthattherehadbeenanalteration,howevertheycouldbemarketed

asasafersystem.

Inconclusion,engineeredsolutionstoinfusionmisconnectionproblemsareneeded.Noadditional

riskshouldbeintroducedwithanynewsystem.TheNICSofferssuchasolution

Ourstudieshavedemonstratedthesystemwouldbeeffectiveatpreventingthesetragicerrors.

Figure1aand1b–ComponentsoftheNICSCentralDrugInfusionLine(patentpending)

References

1. NHS Never events 2. Never Event report 2009-2010 3. JCAHO – Sentinel Alert 4. Ann Pharmacother. 1998 May;32(5):545-8.Extravasation injury associated

with low-dose dopamine.Chen JL, O'Shea 5. M.Evans et al