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Health Science Journal ISSN 1791-809X
2015Vol. 9 No. 1:6
1© Copyright iMedPub | This article is available in: www.hsj.gr/archive
The Effect of Emergency Department Crowding on Patient
Outcomes
Filippatos George1 and Karasi Evridiki2
1 General Hospital of Elefsina “Thriassio”, Greece
2 SW,Non-GovernmentOrganization“Klimaka”, Greece
Correspondence: Filippatos George
Str Karaiskaki 28, N.Penteli, Athens, Greece, P.C.: 15236
Tel: +306977783941
AbstractBackground: Anextremeexcessofpatientsexceedingthecapacityofemergencydepartments (EDs) to provide care is an emerging threat to patient safety andhealthsystemsworldwide.
Aim: The purpose of this literature review was to investigate the effects ofemergencydepartmentcrowdingonpatientsoutcome.
Method and Material: A comprehensive search of the medical literature inPubmed/MEDLINE databasewas performed to identify all original articles thatwerepublishedoravailableon-linebetweenJanuary1,2003,toJanuary1,2013,and related to the concepts of ‘‘emergency department’’ and ‘‘crowding’’ or‘’overcrowding’’.
Results: Of the 1327 studies that were initially retrieved, 484 were excludedbecausetheyhadnorelevancetothetopicand843aftercheckingforeligibilitycriteria.Fromremaining61articles,atotalof35studieswerefinally includedinthereview.Thethreemaincategoriesthatwereconstructedbasedonthestudies,weredelaysintreatmentinterventions,increasedmedicalerrorsoradverseeventsandincreasedmortality.
Conclusions: ThebodyofliteratureinaggregatestronglysuggeststhatEDcrowdingisassociatedwithpotentialofpoorerperformanceandadverseclinicaloutcomes,including mortality. Further research is needed to fully understand the precisemechanism throughwhich crowding adversely affect patient care. PoliciesmustalsobetargetedtoadaptofemergencycaresysteminthefluctuationofinputsforbettercarethattranslatesintobetteroutcomesforpatientsvisitingEDs..
Keywords: Emergencydepartmentcrowding;Patientsafety
IntroductionEmergency department (ED) crowding has been described asthemostseriousproblemthatendangerthereliabilityofhealthcaresystemworldwide[1].TheAmericanCollegeofEmergencyPhysiciansdefinescrowdingasasituationinwhichtheidentifiedneed for emergency services exceeds available resourcesfor patient care in the emergency department, hospital, orboth [2]. The conceptual model partitions ED crowding into 3interdependentcomponents:input,throughput,andoutput[3].
ThecommonlystudiedcauseofcrowdingisdemandforEDcare.Between1997and2007theincreaseintotalannualEDvisitsinUSAwas almost double [4] and between 2001-2008 was 60%
faster than would be expected from population growth [5]. Alarge proportion of all ED visitswere for nonurgent conditionsthat estimated at 37% (range 8%-62%) [6] and from frequentuserswhocomprised4.5%to8%ofallEDpatientsbutaccountedfor21%to28%ofallvisits[7].
Onemainfactorthatmaycausecrowdingisinadequatestaffing.HalfofEDsexceedrecommendedpatienttonurseratioof4:1forroutineEDbeds[8]and68%apatienttonurseratioof1:1forcriticalcarebeds[9].Themeannurse:patientratiosatmorningshiftwere1:15,atafternoonshift1:7andatnight1:4[10].
Hospital bed shortages have been studied as factors thatpotentially affect crowding. Emergency rooms and trauma
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centersinU.S.Adeclinedby3%fromperiod2003-2007[11].Non-availability of ED beds because they are occupied by admittedpatients waiting for transfer from the ED to inpatient unitsrestricttheEDscapacitytoacceptnewarrivalsandconsumeEDsresources[12-14].Arecentstudyconcludedthat,ifcurrentbedusetrendspersistandasthenumbersoffrailolderpatientsriseexponentially,a62%increaseinhospitalbedswillberequiredtomeetexpecteddemandby2050,atacostalmostequal to theentirecurrentAustralianhealthcarebudget[15].
EDcrowdinghasresulted inpoorperformanceonwaitingtimeand length of stay (LOS). In US hospitals the odds of beingexaminedbyaphysicianwithinthetimerecommendedattriagedeclinedby30%from1997to2006[16],waitingtimeincreasedfrom46.5minutesto58.1minutesfromperiodbetween2003-2009[17]andEDLOSincreasedfrom132minutesin2001to154minutesin2005[18].TherewasalargerincreaseamongcriticallyillpatientsforwhomEDLOSincreasedfrom185minutesin2001to254minutesin2005[18].Inotherstudyfoundthatanincreasefrom the 20th to the 80th percentile in ED arrivals resulted inincreasesof42minutes inwaitingtimeand49minutes inLOS[19].
Theobviousoperationalandlogisticproblemscreatedbycrowdinghaveavarietyofundesirableconsequencesonpatients,staffandhospitals[20,21].Thesixdimensionsofqualityincludingsafety,effectiveness, patient-centeredness, efficiency, timeliness, andequitythathasbeendescribedbyTheInstituteofMedicine,mayallbecompromisedwhenpatientsexperiencelongwaitingtimeto seeaphysicianor leavingwithoutbeingexamined,patientsremainsintheEDaftertheyhavebeenadmittedtothehospital,buthavenotbeentransferredtoaninpatientunit,orambulancesaredivertedawayfromthehospitalclosesttothepatient[22].
Therefore, the objective of this review was to describe thescientificliteraturethatinvestigatestheeffectofEDcrowdingonpatientsoutcomes.
Method A comprehensive search of themedical literature in Pubmed/MEDLINE database was performed to identify all scientificarticles thatwerepublishedorwereavailableon-linebetweenJanuary1,2003,toJanuary1,2013,andrelatedtotheconceptsof‘‘emergencydepartment’’and‘‘crowding’’or‘’overcrowding’’.
The inclusive selection criteria were as follows: To be originalarticle,tousecrowdingmeasures,toprovideoddsratio(OR),riskratio(RR)orhazardratio(HR)estimateswithconfidenceintervalsandtobepublishedinEnglish.Weexcludedcommentariesandletters to the editor, original article for causes, solution andmeasures of emergency department crowding and adverseeffectsonpediatricpatients.
Tworeviewers independentlyevaluatedthetitlesandabstractsfor relevance to the topic and subsequently obtained full-textversions of all potentially relevant papers, which were thenfurtherdiscussedamongauthorsforfinalinclusion.
ResultsThe initial search yielded a total of 1327 citations, 484 wereexcludedaftertitle/abstractreviewand782didnotfulfillinclusioncriteria (94% inter-reviewer agreement). After retrieving the
full-textoftheremaining61articles,another26articles,whichfocus on waiting time, delays for diagnostic test and patientsperceptions,relatedtoEDcrowding,wereexcludedfromreview.Finally, only 35papersmeasured theeffectof ED crowdingonpatient outcomes and grouped in three categories: increaseddelaysintreatment,increasemedicalerrorsandadverseeventsand increasedmortality.Aflowchartof studies included in thisreviewispresentedinFigure1.
Delay in treatment interventions Seventeenstudies[23-39]examinedtherelationshipbetweenEDcrowdinganddelay in treatment. Regardingpainmanagement,Hwnagetal.,foundthatduringperiodsofgreaterpatientvolume,hip fracture patients had less documentation of pain on firstassessmentand longertimes topainassessment [23].Patientsexaminedduringperiodsofhighpatientconcentration,tookupto55minuteslongertohavedocumentedpainassessmentwithoutdifferencesinlikelihoodofpainassessment[24].AdministrationofanalgesiaduringhighlevelsofEDcrowdingmeasureswaslesslikelytopatientswithseverepain[25]andotherpainfulcondition[24]whilewasnotstatisticallysignificantinpatientwithback[26]orabdominal[27]painandhipfracture[23].Amongthosewhoreceivedtreatment,EDcrowdingmeasureswereassociatedwithahigherlikelihoodofdelayinbothtimefromtriagetoanalgesiaandtime from roomplacement to analgesia [25,26]. Likely, norelationbetweenworkloadandtimetoanalgesiawasobservedin patientswith fractured neck of femur orwrist and renal orbilliarycolic[28].
Regarding time to antibiotic administration for patients withpneumonia,fivestudiesassociatedincreasedlevelofEDcrowdingwith a decrease in the proportion of community-acquiredpneumonia(CAP)patientsreceivingantibioticswithinfourhours[29-33]. Thetime fromarrival toordera chest radiographwasprolonged by 14.3 minutes and from ordering of antibiotic toadministrationby9.3minutesforevery10additionalEDpatients[30].Theeffectofadditionalpatientsappears tooccurevenatvolumesbelowthemaximumbedcapacity[29].
Overcrowdingwasalsoassociatedwithincreaseddoor-to-balloonanddoor-to-needletimesforthe treatment of acute ST-ElevationMyocardialInfarction(STEMI)[34,35].Incontrast,timetoachieveemergencypercutaneouscoronaryinterventionforacuteSTEMIdid not correlate positivelywith crowding asmeasured by theoccupancyrate[36]andEDlengthofstayorleftwithoutbeingexamined[33].
Time to acute stroke care however, remained the same inthrombolysiseligiblepatientsregardlessofthecrowdingfactor,but not in patients outside of the intravenous thrombolysiswindow, who experienced delays in a CT-scan order andcompletionathigherlevelsofEDcrowding[37].
EDcrowdingasmeasuredbythenumberofpatientsvisits,wasassociated with delays in resuscitation efforts and mortalityduring ED stay. Patients who attended at day with daily visitequaltoorgreaterthan93(dailyEDpatientconcentrationrange57-140) had two-fold increased odds of experiencing delayedresuscitation effort and four-fold increased odds of in-hospitalmortalitycomparedwiththepatientswhoattendedatdaywithdailyvisitlessthan93[38].
Medication treatment time in patientswith acute asthmawas
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associatedwithhighestpercentilesofEDoccupancy.Timetoanebulizer order was 6 minutes longer (95% CI=1-13 minutes),andtimetoasteroidorderwas16minuteslonger(95%CI=0-38minutes)duringcrowdedperiods[39].
Increased medical errors and adverse eventsSixstudies[40-45]assessedtheeffectthatEDcrowdinghadonmedicalerrorsandadverseevents. EDovercrowdingisassociatedwith an increased frequencyofmedicationerrorsmeasured inrealtimebythemodifiedEDWINscore [40]orboardingstatus[41]. Errors included giving medications at incorrect doses,frequencies, durations, or routes and giving contraindicatedmedications [40]. Patients whose average crowding exposurewas in the highest quartile had two-fold increased odds ofexperiencing apreventableadverseeventcomparedtopatientswhose average crowding exposure was in the lowest quartile[42].ForeveryhourspentintheED,theoddsofexperiencinganadverseeventin-hospitalincreasedby3%[43].
Amongpatientswithacutecoronarysyndrome,severalcrowdingmeasures showed three to five times higher rates of adverseoutcomesascardiacarrest,congestiveheartfailure,ventriculartachycardia or fibrillation, supraventricular dysrhythmias,symptomaticbradycardia,hypotensionordeathduringthehighestlevelsofcrowding[44].Highhospitaloccupancywasassociatedwith increased incidence of serious complications defined asshock,needforintubationanddeathwithin24hoursforpatientsadmitted, but still treated in the emergency department and
managed by emergency department providers. The incidenceforseriouscomplicationswas13.62per1000patientdayswhenhospital occupancywas ≤90%, and it increased significantly to17.10and22.52per1000patientdaysforoccupancyat90%-95%and≥95%,respectively[45].
Increased mortality Twelve articles [46-57] specifically examined the associationbetween ED crowding andmortality. Occupancywas linked toincreasedoddsofdeathsat10daysforpatientswhopresentedto one Australian hospital (OR=1.34, 95% CI=1.04–1.72) [46]Usingthesamecrowdingmeasure,patientswithCAPhad9-foldincreased odds of 28-day mortality [47] Hospital occupancy≥100% in combinationwith access block ≥20% occupancywasassociatedwithanincreased2,7and30-daymortality(HR=1.3,95% CI=1.1–1.6, 1.3, 95% CI=1.2–1.5 and 1.2, 95% CI=1.1–1.3respectively)[48].
Mortalityincreasedwithincreasingboardingtime,from2.5%inpatientsboardedlessthan2hours,to4.5%inpatientsboarding12hoursormore(p<0.001)[49].Thein-hospitalmortalitywas17.4%forcriticallyillemergencydepartmentpatientswitha>6-hrdelayinintensivecareunittransfer,versus12,9%forcriticallyill patients who were transferred to intensive care unit in <6-hr (p<.001) [50]. The risk of death amonghigh and low acuitypatientswas1.79and1.71respectivelyformeanlengthofstayof≥6hourscomparedwith<1hour[51].ProlongedEDboardingstaythatexceeded8hourswasassociatedwithincreasedmortalityin
FlowdiagramofarticlesselectionFigure 1
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patientswithnecrotizingfasciitis[52].ThelongEDstaywasnotassociatedwithmortality in patientswith non–STEMI butwasassociatedwithincreasedrateofrecurrentin-hospitalMI[53].
ED crowding, as measured by ambulance diversion at 187 hospitals, was associated with increased inpatient death rateoccurring in thefirst 3days (OR=1.05,95%CI=1.02–1.08) [54].AmongpatientsthatwereadmittedforAMIandexposedto12ormorehoursofambulancediversion,the 30-day,90-day,9-month,and 1-year mortality was increased [55]. The mortality foradmittedtraumapatientsonsignificantdiversiondays,definedasdaywhenhospitalswereondiversionformorethan8hours,wasslightlyhigherthanamongthoseadmittedondaywhenhospitalswereondiversionforfewerthan8hours(3.9%vs.3.3%),butwasstatisticallysignificantat the0.1 level (25%vs14%)amongthemostseverely illpatients[56]. Incontrast,ambulancediversioncontributedto28%reductioninpatientmortalityatanAustralianED[57].
Discussion EDcrowdingisassociatedwithdelaysintreatmentforemergencyconditions, thereby increasing the risk of poorer outcomes.Increased crowding levels, according to this review, wereassociatedwith thepotential of poorerperformance regardingpain management standards, such as timely and appropriateassessmentoranalgesiaonwhichhospitalsare judged[23-27].Delaysornottreatmentofacutepainhasconsequencesbeyondtheimmediateperceptionofsufferingandcannegativelyimpactpatients’well-beingonmultiplelevels[58].
Emergency departments in crowding conditionswere not ableto meet The Joint Commission and the Centers for MedicareandMedicaidServices(CMS)performancemeasurestargetsforpatientswith CAP, that are used as an indicator of the qualityof care, with a 4- hour benchmark [29-33]. Although currentguidelines for treating CAP do not recommend administeringantibiotics within a certain time limit, [59] early time to firstantibiotic dose should be considered as an important markerofoptimalpatientcareinpatientswithCAPratherthanafactorpredictingtheoutcome[60,61].Althougharticlesattemptedtorelatedegradationsinperformancetocrowdedconditions,theirevidence suggests thatperformancebegins todeteriorate longbeforeconditionsintheEDbegintobeidentifiedascrowded[29].
The impactofEDcrowdingontime-sensitiveprocessesofcaresuchasreperfusiontherapyiscontroversial.ThefindingthatEDcrowding,asmeasuredaccordingtoEDWINscore,associatedwith increasedtimetoballooninflationduringPCIforthetreatmentofacuteSTEMI[35]doesnotconfirmbythemuchmorerobust,prospectivedatafromthesameEDinastudydesignedtofollowup that study’s findings [36]. ED crowding was not associatedwith care delays in thrombolysis-eligible patients with stroke[37]butforpatientswithsuspectedacutemyocardialinfarction[34]. The established policies that high prioritize diagnosticand treatment algorithm critically ill patients stroke and acutemyocardialinfarctionmaynotbeaffectedbycompetingresourcedemand[36].
ED crowding exacerbates the rate of medical errors adverseaffectedqualityof care [40-42].Althoughamedicalerrordoesnotnecessarilyimplytheoccurrenceofamedicalharm,patientsexposedatriskofmedicalerrorspotentiallyincreasedtheirrisk
ofadverseevents.Criticallyillpatientsexposedtocrowdingarehighlylikelytobeattributabletoadverseeventscausedbymedicalerrors[44].Theincreasedlikelihoodofseriousadverseeventsisaplausiblemediatoroftherelationshipbetweencrowdingandincreasedlifethreateningcomplications[45].
Adverse events of emergency department crowding have alsobeen linked to fatalities asmeasured by eventualmortality onunselectedadmissionsorspecificpatientsubgroups.Thepossiblerelationshipbetweencrowdingandmortalityacrossstudiesarenotdirectly comparablebecauseofdifferences inED crowdingmeasure,studypopulations,andcase-mixadjustment. Although thesizeof theeffectwasnotconsistentacross themajorityofstudies, considering the adjusted ratio risks that ranging from1.05tomorethan3, thedirectionof theeffectwas [46-52,54-56].Only two studies [53,57]didnotfindassociationbetweenmortality and crowding as measured by ambulance diversionatoneEDinthefirststudy,butwithoutassessmentofpatientsmortalitywhowasdivertedtootherhospital[57]. Inthesecondstudy,EDLOSwereassociatedwithdecreaseduseofguideline-recommendedtherapiesandahigherriskofadverseeventsforpatientswithnon-STEMI[53]. EDcrowdingwasassociatedwithhigher mortalityratebothduringEDstayandupto30daysafteradmission,regardlessofseverityonpresentation.Theincreasedrisk of death for low acuity patients suggests, that processesmightbemorelikelytobreakdownifpatientsarethoughttobelowrisk[51].
This review is consistent with 4 previous reviews [20-22,62]looking at the effects of emergency department crowdingon patients outcomes. Delays in providing needed care andincreasedrisksofmortalityareidentifiedinallarticlesbyaddingdecreased satisfaction [21] and higher probability of leavingtheEDagainstmedicaladviceorwithoutbeingexamined [22].Another article focuses on adversemoral consequences of EDcrowding,ascompromisedprivacyandconfidentiality,impairedcommunication,anddiminishedaccesstocare[62].
The results of the current review should be interpreted in thecontext of some limitations. First, our research is limited onlytothePubmeddatabaseandwemayhavemissedsomestudiespublishedinothersdatabases.Second,theretrospectivedesignof the included studies based on existing patient registers ordatabasescannotexcludethepossibilityofconfoundingthatmayhaveaffectedtheseresults.Accuracyandvariabilityinthequalityofdocumentationamongdifferenthealthcarepersonnelitwasnotfeasibletoensurewithretrospectiveauditofdatabases.Thefindings show considerable variability in crowding measures,timeintervals,patientpopulationsandhospitalstatus,resultingtoinabilitytogeneralize.Finally,nostudydeterminedtheexactmechanism responsible for the association between crowdingandadverseevents,althoughsomeinferencescanbemade.
ConclusionThe body of literature in aggregate strongly suggests that EDcrowding is associated with poorer performance and adverseclinicaloutcomes,includingmortality.Furtherresearchisneededto fully understand the precise mechanism through whichcrowding adversely affect patient care. Policies must also betargeted to adapt of emergency care system in thefluctuationofinputsforbettercarethattranslatesintobetteroutcomesforpatientsvisitingEDs.
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