European Society of Anaesthesiology evidence-based and consensus-based guideline on

23 Pages·2017·0.43 MB·English

Eur J Anaesthesiol 2017; 34:192–214
GUIDELINES
European Society of Anaesthesiology evidence-based and
consensus-based guideline on postoperative delirium
Ce´sar Aldecoa, Gabriella Bettelli, Federico Bilotta, Robert D. Sanders, Riccardo Audisio,
Anastasia Borozdina, Antonio Cherubini1, Christina Jones, Henrik Kehlet, Alasdair MacLullich,
Finn Radtke, Florian Riese, Arjen J.C. Slooter, Francis Veyckemans, Sylvia Kramer, Bruno Neuner,
Bjoern Weiss and Claudia D. Spies2
The purpose of this guideline is to present evidence-based the treatment of surgical patients, a team-based approach
and consensus-based recommendations for the prevention should be implemented into daily practice. This guideline is
andtreatmentofpostoperativedelirium.Thecornerstonesof aimedtopromoteknowledgeandeducationinthepreopera-
theguidelinearethepreoperativeidentificationandhandling tive,intraoperativeandpostoperativesettingnotonlyamong
ofpatientsatrisk,adequateintraoperativecare,postoperative anaesthesiologists but also among all other healthcare pro-
detection of delirium and management of delirious patients. fessionalsinvolvedinthecareofsurgicalpatients.
The scope of this guideline is not to cover ICU delirium.
Considering that many medical disciplines are involved in Published online 9February 2017
Introduction
TheEuropeanSocietyofAnaesthesiology(ESA)iscom- CommitteechosethemembersoftheTaskForce(CDS,
mitted to develop evidence-based clinical guidelines of CA, GB, FB and RDS) based on their clinical and
high quality. The ESA Guidelines Committee selected methodological expertise. The Task Force elected its
the ‘Reduction of Postoperative Delirium’ as a topic of chairperson,bycommonconsent,attheirfirsttelephone
interest and dedicated a Task Force – established in conference on 15 March 2013, and the ESA formally
March2013 – tocoverthismatter.TheESAGuidelines confirmed this election during the first constitutional
meeting at the European Anaesthesiology Congress in
Barcelonaon2June2013.FollowingthefirstTaskForce
ThisarticleisaccompaniedbythefollowingInvited
meeting,membersoftheAdvisoryBoardwerechosenby
Commentary:
theGuidelinesCommitteeandtheTaskForcebasedon
Steiner LA. Postoperative delirium guidelines. The their clinical and methodological expertise in regard to
greatertheobstacle,themoregloryinovercomingit. thekeyquestionsasagreedbytheTaskForceinBarce-
Eur J Anaesthesiol 2017; 34:189–191. lonainJune2013(Table1).TheTaskForcereceivedits
entire financial support from the ESA, without any
FromtheDepartmentofAnesthesiologyandIntensiveCareMedicine,Charite´CampusVirchow-KlinikumandCharite´CampusMitte,Charite´ –Universita¨tsmedizinBerlin,
Berlin,Germany(FR,SK,BN,BW,CDS);DepartmentofAnesthesiology,FacultaddeMedicinadeValladolid,HospitalUniversitarioRioHortega,Valladolid,Spain(CA);
DepartmentofGeriatricSurgery;DepartmentofAnaesthesia,AnalgesiaandIntensiveCare,ItalianNationalResearchCentresonAging/IRCCS,Ancona(GB);Department
ofAnesthesiology,CriticalCareandPainMedicine,‘Sapienza’UniversityofRome,Rome,Italy(FB);DepartmentofAnaesthesiology,UniversityofWisconsin,Madison,
Wisconsin,USA(RDS);DepartmentofSurgery,St.HelensHospital,Merseyside;UniversityofLiverpool,Liverpool,UnitedKingdom(RA);PetrovskyNationalResearch
CenterofSurgery,Moscow,Russia(AB);GeriatriaedAccettazioneGeriatricad’Urgenza,IRCCS-INRCA,Ancona,Italy(AC);WhistonHospital,Prescot,Merseyside,
United Kingdom (CJ); Section of Surgical Pathophysiology and The Lundbeck Centre for Fast-track Hip and Knee Arthroplasty, Copenhagen University Hospital,
Rigshospitalet,Copenhagen,Denmark(HK);EdinburghDeliriumResearchGroup,GeriatricMedicineUnit,UniversityofEdinburgh,Edinburgh,UnitedKingdom(AM);
DepartmentofAnaesthesia,AnæstesiologiskAfdeling,Næstved,Denmark(FR);PsychiatricUniversityHospital,Zurich,Switzerland(FR);DepartmentIntensiveCare
MedicineandBrainCentreRudolfMagnus,UniversityMedicalCenterUtrecht,Utrecht,TheNetherlands(AJCS);Serviced’Anesthe´siologie,CliniquesuniversitairesStLuc,
Brussels,Belgium(FV)
CorrespondencetoProfClaudiaD.Spies,DepartmentofAnaesthesiologyandIntensiveCareMedicine,Charite´ –Universita¨tsmedizinBerlin,Charite´CampusVirchow-
KlinikumandCharite´ CampusMitte,D-10117Berlin,Germany
Tel:[phone]/þ4930450531052;fax:[phone];e-mail:[email protected]
1AntonioCherubinirepresentedtheEuropeanUnionGeriatricMedicineSociety(EUGMS).
2ClaudiaD.SpieswastheelectedchairoftheTaskForce.
0265-0215Copyright(cid:2)2017EuropeanSocietyofAnaesthesiology.Allrightsreserved. DOI:10.1097/EJA.0000000000000594
Evidenceandconsensus-basedguidelinesonpostoperativedelirium 193
Table1 KeyquestionsasagreedbytheTaskForceinBarcelona, Duringitsmeetings,theTaskForceagreedonseveralkey
June2013
questions (Table 1). To answer these questions and to
Keyquestion Statements develop evidence-based recommendations, search strat-
egies included PubMed, Cochrane, Scopus, ISI Web of
Whatispostoperativeandwhatispostinterventional 7/7
delirium knowledge and Embase up to March 2015. Afterwards,
Whatisemergencedelirium(inadequateemergence)? 7/7 onlyselectednewpublishedarticlesinrespectofcurrent
(cid:3) WhatareriskfactorsforPOD? 6/8
clinicalpracticewereconsidered.Searchtermswere(delir-
* Predisposing(pre-intra-postoperative)
* Precipitating(pre-intra-postoperative) iumORconfusionORconfusion(cid:2)ORdisorientationOR
Whatmeasurescanbetakentodeterminetheindividual 6/8 bewilderment) AND (postoperative OR postoperative
riskofpatients? period OR postoperative period(cid:2) OR post surgical OR
Whenshouldariskevaluationbeperformed? 8/8
(cid:3) Preoperativephase 7/8 postsurgicalORanesthesiarecoveryperiodORanesthesia
* Whichpharmacologicalinterventionscanbe recoveryperiod(cid:2)ORpostanesthesia).Thesearcheswere
recommendedforwhichsubgroupofpatients?
performedbetweenJanuary2014andMarch2015.These
* Whichmedication/actionsshouldbeavoided?
searches led to 9425 hits. After automated and manual
* Whichnonpharmacologicalinterventionscan
berecommended? removal of duplicates, 5779 hits were screened for
& Whichsupportivestrategiesarebeneficial? relevance. Relevant articles included existing systematic
& Istheuseofchecklists/algorithmsusefuland
and narrative reviews, editorials, meta-analyses, random-
doesitaffectincidence,severityorduration
ofPOD? isedcontrolledtrials(RCTs),cohortstudies,case–control
(cid:3) Intraoperativephase 8/8 studies and cross-sectional studies. Case (series) reports
* Whichpharmacologicalinterventionscanbe
were not included but screened for relevant references.
recommendedforwhichsubgroupofpatients?
* Whichmedication/actionsshouldbeavoided? We additionally used the ‘Cited by xx PubMed Central
* Whichnonpharmacologicalinterventionscan articles’ function in PubMed to identify potentially
berecommended?
& Whichsupportivestrategiesarebeneficial?
& Howshouldanaesthesiabeconductedto Fig.1
avoidPOD?
(cid:3) Postoperativephase 8/8
* Whichpharmacologicalinterventionscanbe 9425 hits
recommendedforwhichsubgroupofpatients? • PubMed 2547 hits
& Whichmedication/actionsshouldbe • Cochrane 288 hits
avoided? • Embase 4370 hits
* Howshouldpainmanagementbeconductedin • Scopus 650 hits
thepostoperativephasetopreventdelirium?
• ISI Web of Science 1653 hits
* Isthereevidenceforanalgorithm(likethePain-
Agitation-DeliriumManagementonICUs)that
canbeapplied?
WhichtoolsshouldbeusedtomonitorforPOD? 8/8 1649 automated duplicate removal
Whichtoolshouldbeusedtomonitorpostoperative 7/8
pain?
1997 manual duplicate removal
WhenshouldPODbemonitored? 7/8
HowoftenshouldPODbemonitored? 8/8
WhatarereversiblecausesofPOD? 7/8
Howcansymptomsbeevaluatedobjectively? 8/8 5779 abstracts screened
Whenshouldpharmacologicalinterventionsbe 8/8
conducted?
Whichpharmacologicaltreatmentcanbeused? 7/7
WhereshouldPODbetreated? 7/7
5460 publications excluded
Whichnonpharmacologicaltreatmentcanbe 7/7
conducted? • No surgical patients
• No outcome data regarding one of our key questions
& Geriatricpatients
AretheredifferencesinthemanagementofPODin 8/8 • Not relevant to one of the key questions
geriatricpatients? • Case report or case series report
Isthereevidenceforabeneficialpre-,peri-,and 7/7 • Health economics or other nonclinical investigation
postoperativetreatmentalgorithmregardingPOD?
Howtomanagedeliriumsuperimposedonapreexisting 8/8
dementia/cognitivedisorder? 319 publications included by March 2015
POD,postoperativedelirium.
85 publications suggested by members of task force and
involvement from the healthcare industry. Sub-commit-
advisory board
teeswereestablishedtoaddressthequestionsofinterest.
Evidence-based and consensus-based 404 publications included by October 2015
methods
The guideline was designed following the ‘Appraisal of Flowchartofthestudyselectionprocess.
GuidelinesforResearchandEvaluation(AGREEII)’.1–3
Eur J Anaesthesiol 2017; 34:192–214
194 Aldecoaetal.
overlooked but relevant articles. We also screened the Moreover, POD (refer to the specific definition in the
referencelistsofrelevantarticlesforfurtherpublications ‘Paediatricpatients’section)isacommoncomplicationin
andincludedreferencessuggestedbythemembersofthe children of pre-school age (5 to 7 years): whether this is
Task Force and the advisory board. Overall, 405 articles due to age-related psychological issues or to additional
wereincludedintheguideline(Fig.1).Relevantarticles inflammatory effects on the brain cannot currently be
were graded according to their level of evidence (LoE) determined. There is a limited number of studies on
using theCritical Appraisal Worksheets from theCentre cognitiveoutcomesinchildren.7FortheUSA,theFood
for Evidence-Based Medicine of the University of andDrugAdministration (FDA)recentlyrecommended
Oxford.4 The grade of recommendation (GoR) was cautious indications for anaesthesia and surgery in chil-
obtained on the basis of the LoE of the literature dren aged less than 3 years.8 In Europe, the ESA
(Table 2) and the consensus expert opinions by the launchedaninitiative,theEUROpeanSafeTotsAnaes-
majority((cid:4)75%)oftheTaskForceandtheadvisoryboard. thesia Research (Eurostar) Initiative Task Force to
Expertshadtodiscloseaconflictofinterestbeforeparti- promotetranslationalresearchonanaesthesianeurotoxi-
cipatingintheconsensus-basedvotingonanyrecommen- cityandlong-termoutcomesafterpaediatricanaesthesia
dation.Expertswereexcludedfromvotingifaconflictof and surgery.9
interestrelatingtoanyrecommendationwaspossible.For
In addition, POD is more common in all age groups if
allstatements,thestrengthoftherecommendationisprefacedby
precipitating risk factors such as major surgery10–13 or
theGRADEphrase‘werecommend’forstrongrecommendations
emergency surgery14–19 are present. The incidence
(GoRA)orbytheGRADEphrase‘wesuggest’forconditional
increaseswithahighburdenofcomorbiditiespresenting
recommendations(GoRB).
as multiorgan dysfunction before surgery, for example
Thefinaldraftoftheguidelinewaspeer-reviewedbythe low haemoglobin concentration,20–23 low ejection frac-
relevantsub-committeesoftheESA’sScientificCommit- tion,16carotidarterystenosis,24orhighserum creatinine
tee. The reviewed draft was made available between 8 concentration.25–28PODisassociatedwithseveralnega-
October2015and7November2015ontheESAwebsite tiveclinicalconsequences,includingmajorpostoperative
for critical appraisal by ESA members. The final manu- complications, cognitive decline, distress, longer hospi-
script of the guideline was approved by the Guidelines talisation with increased costs and higher
CommitteeandBoardoftheESAbeforepublication.The mortality.17,20,29–36Therefore,preventionofPODshould
guidelinesexpireafter5yearsunlessupdatedearlier. betheaiminallpatients;ifitcannotbeprevented,itis
essential to intervene immediately.29,37–39
Background
Postoperative delirium (POD) is an adverse postopera- Definition
tive complication that can occur in patients of any age, Delirium is defined by either the Diagnostic and Stat-
from children to the elderly. Its incidence varies in the isticalManualofMentalDisorders,FifthEdition(DSM-
various age groups and is substantially influenced by 5)40orbythe10threvisionoftheInternationalStatistical
patient-related risk factors that are variably distributed Classification of Diseases and Related Health Problems
anddifferentiallyaccumulateinthedifferentagegroups. (ICD10,Table3).41Deliriumisanacuteandfluctuating
Elderly patients are generally thought to be at higher alteration of mental state of reduced awareness and
risk because predisposing risk factors such as cognitive disturbanceofattention.PODoftenstartsintherecovery
impairment,comorbidity,sensorialdeficits,malnutrition, room and occurs up to 5 days after surgery.42–44 One
polymedication,impaired functionalstatusand frailty(a investigation43 found that many patients with POD on
conditionthatcanonlybeobservedamongagedpatients) the peripheral ward already had POD in the recovery
accumulate and overlap with ageing. room.
Table2 Fromevidencetorecommendations(modifiedfromGRADE5andTheEuropeanCouncilRecommendation6)
LoE GoR Wordingofthestatements
LevelofEvidence(LoE)fromtheCentreforEvidence-Based Consideredjudgement–groupdecision
MedicineoftheUniversityofOxford
High A–strongrecommendation Werecommend
Dataderivedfrommultiplerandomisedclinicaltrialsormeta- Evidenceand/orgeneralagreementthatagiventreatmentor
analyses procedureisbeneficial/useful/effective
Moderate B–recommendation Wesuggest
Dataderivedfromasinglerandomisedclinicaltrialorlarge Conflictingevidenceand/oradivergenceofopinionabout
nonrandomisedstudies thetreatmentorprocedure,howeverevidence/opinionis
infavourofusefulness/efficacy
Weak Notconsidereda
Consensusofopinionoftheexpertsand/orsmallstudies,
retrospectivestudiesandregistries
aIfevidenceorgeneralagreementthatthegiventreatmentorprocedureisnotuseful/effectiveorinsomecasesmayevenbeharmful,theinformationisincludedinthe
manuscript,butnostatementsaregiven.
Eur J Anaesthesiol 2017; 34:192–214
Evidenceandconsensus-basedguidelinesonpostoperativedelirium 195
Table3 DefinitionofdeliriumGoldstandardaccordingtotheDiagnosticandStatisticalManualofMentalDisorders,FifthEdition,40orthe
10threvisionoftheInternationalStatisticalClassificationofDiseasesandRelatedHealthProblems41
ICD-10criteria(F05.0)Delirium,notinducedbyalcoholandother
psychoactivedrugsandnotsuperimposedondementia DSM-5criteria
Anaetiologicallynonspecificorganiccerebralsyndromecharacterised Adisturbanceinattention(i.e.reducedabilitytodirect,focus,sustain
byconcurrentdisturbancesofconsciousnessandattention, andshiftattention)andawareness(reducedorientationtothe
perception,thinking,memory,psychomotorbehaviour,emotionand environment)
thesleep–wakeschedule.Thedurationisvariableandthedegreeof
severityrangesfrommildtoverysevere
Diagnosticcriteria: Thedisturbancedevelopsoverashortperiodoftime(usuallyhourstoa
fewdays),representsachangefrombaselineattentionand
awareness,andtendstofluctuateinseverityduringthecourseofa
day
A.Cloudingofconsciousness,thatisreducedclarityofawarenessof Anadditionaldisturbanceincognition(e.g.memorydeficit,
theenvironment,withreducedabilitytofocus,sustainorshiftattention disorientation,language,visuospatialabilityorperception
B.Disturbanceofcognition,manifestbyboth: Thedisturbancesincriteriaaandcarenotbetterexplainedbyanother
preexisting,establishedorevolvingneurocognitivedisorderanddo
notoccurinthecontextofaseverelyreducedlevelofarousal,suchas
coma
(1)Impairmentofimmediaterecallandrecentmemory,withrelatively Thereisevidencefromthehistory,physicalexaminationorlaboratory
intactremotememory;and findingsthatthedisturbanceisadirectphysiologicalconsequenceof
anothermedicalcondition,substanceintoxicationorwithdrawal(i.e.
duetoadrugofabuseortoamedication),orexposuretoatoxin,oris
duetomultipleaetiologies
(2)Disorientationintime,placeorperson
C.Atleastoneofthefollowingpsychomotordisturbances:
(1)Rapid,unpredictableshiftsfromhypoactivitytohyperactivity
(2)Increasedreactiontime;
(3)Increasedordecreasedflowofspeech
(4)Enhancedstartlereaction
D.Disturbanceofsleeporthesleep–wakecycle,manifestbyatleast
oneofthefollowing:
(1)Insomnia,whichinseverecasesmayinvolvetotalsleeploss,with
orwithoutdaytimedrowsiness,orreversalofthesleep–wakecycle
(2)Nocturnalworseningofsymptoms
(3)Disturbingdreamsandnightmareswhichmaycontinueas
hallucinationsorillusionsafterawakening
E.Rapidonsetandfluctuationsofthesymptomsoverthecourseofthe
day
F.Objectiveevidencefromhistory,physicalandneurological
examinationorlaboratorytestsofanunderlyingcerebralorsystemic
disease(otherthanpsychoactivesubstance–related)thatcanbe
presumedtoberesponsiblefortheclinicalmanifestationsinAtoD
DSM-5,DiagnosticandStatisticalManualofMentalDisorders,FifthEdition;ICD-10,10threvisionoftheInternationalStatisticalClassificationofDiseasesandRelated
HealthProblems.
VeryearlyonsetofPODintheimmediatepostanaesthe- toamaximumof60daysis3%afterelectivesurgeryand
sia period before or on arrival at the recovery room is nearly 10% after emergency surgery.55 In addition to
referred to as ‘emergence delirium’.45–49 In children, mortality, postoperative cognitive impairments such as
paediatric emergence delirium (paedED) may present POD and postoperative cognitive dysfunction (POCD)
with purposeless agitation with kicking, absence of eye impose a huge burden on individuals and society.39
contact with caregivers or parents (with eyes staring or
TheincidenceofPODisdependentonperioperativeand
averting),inconsolabilityandabsenceofawarenessofthe
intraoperative risk factors.57 Therefore, the incidence of
surroundings.50
POD varies within a broad range.58,59 For example, a
Deliriumcanpresentashypoactive(decreasedalertness, meta-analysisof26studiesofPODreportedanincidence
motor activity and anhedonia), as hyperactive (agitated of4.0to53.3%inhipfracturepatientsand3.6to28.3%in
and combative) or as mixed forms.51,52 Increased age elective patients.60
seems to be a predisposing factor for the hypoactive
POD, and delirium in general, is often regarded as a
form.51,53 The prognosis may be worse with hypoactive
temporaryattenuationofbrainfunction,usuallyfollowed
delirium,possiblyduetorelativeunder-detectionbystaff
byafullremission.However,strongevidenceexiststhat
and consequently delayed treatment.51
POD is linked with longer term cognitive and noncog-
nitivemorbidityaswellasreducedqualityoflife.Itisalso
Relevance associatedwithincreasedmortalityintheshorttermand
Morethan230millionsurgicalproceduresareperformed long term. The impact of POD on mortality has been
eachyearworldwide,ofwhichmorethan80millionarein foundacrossdifferentsurgicaldisciplines,inelectiveand
Europe.54–56InEurope,thein-hospitalmortalityrateup emergency surgery.17,20,23,24,29,31–33,36,61–71 Only a few
Eur J Anaesthesiol 2017; 34:192–214
196 Aldecoaetal.
studies, some of them after adjustment for preoperative thecomplexunderlyingpathologicalmechanismleading
cognitive status, found no72–77 or only borderline78 to increased vulnerability to POD.
association between POD and mortality.
In addition to the above statements, emergency
Thereis evidence that POD is associated with deterior- surgery14–19,155 and postoperative complications156
atingcognitioninboththeshortterm(months)andlong increase the risk of higher rates and prolonged duration
term((cid:4)1year)afteritsoccurrence.39,79–81Oftenreferred of POD as well as long-term cognitive impairment.157
to as postoperative cognitive dysfunction (POCD), Protocols are required to identify these risk factors
altered cognition has been found shortly after POD in and to implement risk reduction strategies (e.g. fast
the ICU setting.82–84 Some investigators have found track).105,158,159
POD to be associated with POCD up to 12 months
Hypothermiaonadmissiontotherecoveryroomhasalso
postsurgery30,78,85,86 and even associated with dementia
been reported to be a risk factor for hypoactive emer-
up to 5 years after POD.68 In addition, POD has been
gence.49 In addition, preoperative fasting glucose con-
associated with posttraumatic stress disorder 3 months
centrations are associated with more delirium after
after surgery.87
cardiac surgery.128,160 Despite existing evidence on
POD increases total hospital length of stay biomarkers for the detection and monitoring of POD
(LOS).13,15,20,23,31,34,84,88–96 POD on day 1 after surgery from both the ICU setting93,161,162 and the non-ICU
is most predictive of hospital LOS.13 In addition, even setting,14,116,163–169 their use in clinical routine cannot
POD in the recovery room has been associated with currentlyberecommended; furtherresearchisrequired.
increased total hospital LOS.13 After discharge, patients
with POD have an increased level of care depen-
Monitoring of postoperative delirium
dency20,23,30,32,34–36,61,89,92 or limitations in basic activi-
EarlydiagnosisofPODiscriticaltotriggerfocussedand
ties of daily living up to 12 months.31
effectivetreatment.29,37–39,79,80Patientsshouldnotleave
Because patients can present with both delirium and the recovery room without being screened for POD.
cognitiveimpairmentbeforesurgery,preoperativeevalu- Current reference standards for diagnosing delirium,
ation ofpatientsfor thepresenceof delirium andcogni- includingPOD,aretheDSM-540ortheICD1041(Table
tive impairment should be considered. Of note, studies 3). Extensive training is required to use these reference
that evaluated delirium on admission, that is before standards.105 In addition, the new definition of DSM-5
surgery, reported prevalence rates between 4.4 and comparedwith DSM IV-TRdecreases the sensitivity to
35.6%.92,97–104Cognitiveimpairmentatanytimeduring diagnosedeliriumbecausethedisturbancesdonotoccur
surgical stay,including preoperativedelirium, wasarisk inthecontextofaseverelyreducedlevelofarousal.170,171
factorinhipfracturepatientsforpoorfunctionaloutcome However,theDSM-5guidancenotesclarifythis,stating
12 months later.104 Any cognitive impairment before thatpatientswithaseverelyreducedlevelofarousal(of
hospital admission was an independent risk factor for acute onset) above the level of coma should be con-
worse longer term cognitive impairment.104,105 sideredashaving‘severeinattention’andhenceashaving
delirium.40,172Asthisisrelevantinthepostoperativeand
ICUsetting,itisimportantthatbothasedation/agitation
Risk factors tool such as the Richmond Agitation-Sedation Scale173
A widely accepted model of delirium differentiates pre- (RASS; Table 5)and a delirium screeningtool are used.
disposing factors (that are related to the patient) and
A delirium screening system suitable for use in the
precipitating factors (that trigger the onset of delir-
recovery room should be easily applicable and fast to
ium).106 The risk of developing delirium can be seen
perform.44 A high sensitivity (to detect POD as early as
as the product of predisposing and precipitating factors.
possible)maybeachievedwithtwoscores – theNursing
Risk assessment is considered as the responsibility of
Delirium Screening Scale174 (Nu-DESC) and the Con-
different disciplines and should be implemented in the
fusion Assessment Method (CAM).44,176 However, in a
perioperative clinical pathway.
recentstudy,thesensitivitiesofbothofthesetestswere
Theevidence-basedandconsensusstatementsandtheir lower than expected,177 and it is to be noted that the
GoR for preoperative, intraoperative and postoperative CAM has a low sensitivity when not used by staff
riskfactorsforPODarelistedinTable4.Asmanystudies specially trained in its use. In the latter study reporting
identified advanced age asa risk factorfor POD both in lower sensitivities despite a high methodological stan-
univariate and in multivariate analysis, we show the dard, the measurements were performed in a prolonged
evidenceintwocolumns(alladultsvs.elderly(cid:4)65years timeframeof60min,thatistooslowtoassessthesudden
of age) according to the inclusion criteria of the cited changes in the recovery room seen in this patient popu-
studies. In the medical literature, elderly patients are lation.177 The study reporting a higher sensitivity was
often defined as aged at least 65 years.105 However, embedded in an accreditation process in which all team
chronologicalagemaybeaninsufficientproxytocapture members – nurses and physicians – were educated
Eur J Anaesthesiol 2017; 34:192–214
Evidenceandconsensus-basedguidelinesonpostoperativedelirium 197
Table4 Evidence-basedandconsensus-basedstatementsregardingriskfactors
Agegroup(inclusioncriteria)
Statements LoE Alladults Elderly>65years GoR
–
WesuggestevaluatingthefollowingpreoperativeriskfactorsforPOD
(cid:3) Advancedage [10],1b;[14],2b;[17],4;[18], [10,14,17,20, [18,35,76,105,111–113, B
2b;[20],2b;[34],2b;[35], 34,107,108,112, 114,117,119,119]
2b;[76],2b;[105],5 113,116,118]
[107],2b;[108],2b
[109],2b;[110],2b
[111],2b;[112],2b
[113],2b;[114],2b
[115],2b;[116],2b
[117],2b;[118],2b
[119],2b
(cid:3) Comorbidities(e.g.cerebrovascular [17],4;[20],2b;[21],2b;[71], [17,20,110,112, [21,103,123,125,126,130,132] B
includingstroke,cardiovascular, 4;[103],2b 121,124,127,128]
peripheralvasculardiseases,diabetes, [108],1b;[112],2b
anaemia,Parkinson’sdisease, [121],2b;[122],1b
depression,chronicpainandanxiety [123],2b;[124],3b
disorders) [125],2b;[126],4
[127],2b;[128],2b
[130],1b;[131],2b
[132],2b
(cid:3) Theresultsofcomorbidityscoressuch [28],2b;[34],2b;[89],2b; [28,34,135] [89,94,122,133,134] B
astheAmericanSocietyof [96],4;[122],4;[133],2b;
Anesthesiologists’physicalstatus [134],4;[135],4
classificationsystem(ASA-PS)orthe
CharlsonComorbidityIndex(CCI)orthe
ClinicalImpairmentAssessmentScore
(CIAS)beforesurgery
(cid:3) Preoperativefluidfastingand [13],2b;[112],2b [13] [112],Incl.(cid:4)18years,obsvd.66(cid:5)11years, B
dehydration range58to72years
(cid:3) Hyponatraemiaorhypernatraemia [34],2b;[110],1b [34,135,136] [110],Incl.(cid:4)60years,obsvd.75years B
[135],4;[136],4
(cid:3) Drugswithanticholinergiceffects(e.g. [92],4;[109],2b [137,139,140] [92,109,113],Incl.(cid:4)50years,obsvd.67(cid:5)9 B
measuredbyananticholinergicdrug years;[115,138],Incl.(cid:4)18years,obsvd.
scale) 68(cid:5)8years,range46to88years
[113],2b;[117],2b
[137],4;[138],4
[139],4;[140],4
Werecommendevaluatingalcohol-related [20],2b;[23],2b;[34],2b; [20,34,116],Incl. [23],Incl.(cid:4)50years,obsvd.64(cid:5)9years, A
disorders(ICD-10)/alcoholusedisorders [71],4;[105],5;[116],2b; none,mean63 PODþ,69(cid:5)9years,POD(cid:6),61(cid:5)6years;
(DSM-5)asafurtherpreoperativerisk [138],2b;[141],2b years,range24to [71,105,138,141],Incl.(cid:4)18years,obsvd.
factor 90years 68(cid:5)8years,range46to88years
[142],nofulltext
WesuggestconsideringthefollowingintraoperativeriskfactorsforPOD
(cid:3) Siteofsurgery(abdominaland [13],2b;[23],2b;[34],2b [13,34] [23],Incl.none,obsvd.PODþ,69years, B
cardiothoracic) POD(cid:6),61years
(cid:3) Intraoperativebleeding [42],2b;[128],2b [128,143–145] [42],Incl.none,obsvd.PODþ71years,POD(cid:6), B
61years
[143],2b;[144],2b
[145],4
Werecommendconsideringdurationof [16],2b;[116],2b [16,116,136,149] [147],Incl.(cid:4)60years,obsvd.72years;[148], A
surgeryasafurtherintraoperativerisk Incl.>60years,obsvd.PODþ,76.1(cid:5)6.1
factor years,POD(cid:6),69.8(cid:5)6.0years;[144],Incl.
(cid:4)60years,obsvd.72years
[136],4;[146],4
[147],2b;[148],2b
[149],2b
Werecommendevaluatingpainasa [13],2b;[49],2b;[93],2b; [13,49] [93],Incl.(cid:4)60years,obsvd.72years; A
postoperativeriskfactorforPOD [103],2b;[129],2b [103,129,150],Incl.(cid:4)60years,obsvd.75
years;[152],Incl.(cid:4)50years,obsvd.66years;
[153];[154]
[150],4;[151],nofulltext;
[152],2b;[153],1b;[154],
2b
Datapresentedasreferencenumber,GoR,gradeofrecommendation(strong¼A,conditional¼B);LoE,levelofevidence;Incl.,inclusioncriterion;obsvd.,observed;
POD,postoperativedelirium.
Eur J Anaesthesiol 2017; 34:192–214
198 Aldecoaetal.
Table5 RichmondAgitation-SedationScaletoassesssedation whereas the Pediatric Anesthesia Emergence Delirium
depths169
(PAED)scale(Table7)wasusedinchildren.181
þ4 Combative Violent,immediatedangertostaff
Intherecoveryroomsetting,thefollowingdeliriumscores
þ3 Veryagitated Pullsorremovestube(tubes)or
catheter(catheters);aggressive have undergone validation against the criteria according
þ2 Agitated Frequentnon-purposefulmovement, to the DSM:
fightsventilator
þ1 Restless Anxious,apprehensivebutmovements
notaggressiveorvigorous (1) Nu-DESC44,174,177 reported sensitivity between 32
0 Alertandcalm and 95% and reported specificity up to 87%.44 If
(cid:6)1 Drowsy Notfullyalert,buthassustained
sensitivityinthedifferentrecoveryroomsettingisin
awakeningtovoice(eyeopening
andcontactformorethanorexactly thelowerrange,itmaybeadvisabletouseathreshold
10s) of at least 1 point to increase sensitivity to 80%.177
(cid:6)2 Lightsedation Brieflyawakenstovoice(eyeopening
andcontactfor<10s) (2) CAM43,44,105,176 or the CAM-ICU.178 In a post-
(cid:6)3 Moderatesedation Movementoreyeopeningtovoice(but anaesthesia care unit (PACU), sensitivity has been
noeyecontact)
reported between 28 and 43%, with a specificity of
(cid:6)4 Deepsedation Noresponsetovoicebutmovementor
eyeopeningtophysicalstimulation 98%.45,177
(cid:6)5 Unrousable Noresponsetovoiceorphysical
stimulation
In special patient populations, other scores have been
Theusualtarget/aimofalertnessiswithinthegreyrectangle. used, and diagnostic validity has been assessed.
Although, these scores might be applicable and have
beforeimplementingqualityindicatorsfordelirium,pain been validated regarding standards (not necessarily
and postoperative nausea and vomiting assessment in DSM),theyhaveeitherbeenassessedinspecialpatient
the recovery room.44 More research is needed regarding populations or in settings different from the postopera-
the optimal tools for detection of delirium in the tive setting. Some of these scores, such as the Delirium
recovery room. RatingScale-98182ortheMemorialDeliriumAssessment
Scale,183 might be useful to evaluate postoperative
If POD is detected, patients should not be discharged
patients,buttheymighttakelongertoperforminabusy
from the recovery room to the ward without having
recovery room setting. Several scores can be used as
started aetiology-based and symptom-based treat-
alternatives: the Bedside Confusion Scale,184 Clinical
ment.179 This is because the longer the duration of
Assessment of Confusion,139 Confusion Rating Scale,186
deliriumandthelaterthetreatmentisstarted,themore
theDelirium-O-Meter,187DeliriumObservationScreen-
cognitive decline may be expected.39,79 On the post-
ing,188 the delirium symptom interview (DSI),189 the
operative ward, POD should be monitored at least once
Neelon and Champagne Confusion Scale190 or the 4
per shift due to the fluctuating course of POD.175 The
‘A’s Test.191
evidence-basedandconsensus-basedstatementsregard-
ing POD monitoring are listed in Table 6. In general, the team (including nurses and physicians)
should be involved in the choice of which score to use.
PODscreeningisrecommendedbyusingstandardisedrating
For routine implementation, it is mandatory to train the
scales validated for the postoperative setting. The scales
team on the basic features of delirium as well as the
usuallytakelessthan1mintocomplete.Onlythosescores
features of any tools that will be used. This is not only
that are validated for the recovery room or the peripheral
becausescoressuchasCAMrequiretraining,whereasthe
ward with an adequate sensitivity are listed below. Scores
NuDesc does not, but also because the team needs to
validatedonlyfortheICUorothersettingsarenotlisted.
haveacommonunderstandingofdeliriumandtobeable
Foremergencedeliriumimmediatelyaftersurgery,agitation to communicate consistently on the results of tools
scalessuchastheRASS173wereusedinallstudies,47–49,180 used.105,192
Table6 Evidence-basedandconsensus-basedstatementsregardingmonitoringofpostoperativedelirium
Agegroup(inclusioncriteria)
Statements LoE Alladults >65years GoR
–
WerecommendscreeningforPODin [42],2b;[44],2b;[178],2b [44,178] [42] A
allpatientsstartingintherecovery
roomandineachshiftupto
postoperativeday5
Werecommendusingavalidated [44],2b;[172],2b [44,172,178] [175] A
deliriumscoreforPODscreening
[175],2b;[178],2b
Datapresentedasreferencenumber,GoR,gradeofrecommendation(strong¼A,conditional¼B);LoE.LoE,levelofevidence;POD,postoperativedelirium.
Eur J Anaesthesiol 2017; 34:192–214
Evidenceandconsensus-basedguidelinesonpostoperativedelirium 199
Table7 ThePediatricAnesthesiaEmergenceDeliriumscale179 Inaddition,itisimportanttonotethatnotallscoresare
available in different languages. Therefore, national
Item
societies might consider validating the scores in the
1 Thechildmakeseyecontactwiththecaregiver
language in which it is to be applied.
2 Thechild’sactionsarepurposeful
3 Thechildisawareofhis/hersurroundings
4 Thechildisrestless Prevention and treatment
5 Thechildisinconsolable
Preventionandtreatmentoptionsareavailabletoreduce
Items1,2and3arereversescoredasfollows:4¼notatall,3¼justalittle, the incidence and duration of POD. If POD occurs,
2¼quiteabit,1¼verymuch,0¼extremely.Items4and5arescoredasfollows: immediatetreatmentofbothcausativefactorsandsymp-
0¼notatall,1¼justalittle,2¼quiteabit,3¼verymuch,4¼extremely.The
scores of each item were summed to obtain a total Pediatric Anesthesia toms has a major impact in reducing its duration29,37–39
EmergenceDeliriumscalescore.Thedegreeofemergencedeliriumincreased (Fig.2).Theevidence-basedandconsensus-basedstate-
directlywiththetotalscore.
ments regarding prevention and treatment are listed in
Table 8.
Fig.2
Pre-operative Anaesthesia Recovery room Ward
Assessment
A.: (low risk and high risk patients) .A: (low risk and high risk patients)
Avoid benzodiazepines for Avoid benzodiazepines (except
. premedication except anxiety . withdrawal) All patients: All patients:
Prevention B...: (HCMAMigovainhoninii smdrtiia dusaiemnnkr t d(iaflcaaluhpdyioh-ddnla iifin-tga2ieohs rattngg irn/iohcsgny e dttitshrim uAtmsge sobligatory)) As.f .+A BAc:o Hdneitgqinhuu aroitsueks p (iaanidfnud scitoioinonnt roaofll/ os(mpetiuo Alitd iosmbolidgaalt)ory) Non-oppMparhiunoealadtvli rgmsemeponsadirataaini.cl,ogonl4o)gical Non-pprhoepMaaviourneilmadtnli gmsateposicadoiraoain.nl,lg4o)gical
Low risk A A
High risk A+B A+B > cut-off > cut-off > cut-off > cut-off
Assess pain: Assess pain: Assess pain: Assess pain:
Observer-based Start self-assessment Observer-based Start self-assessment
All patients:
g Start risCkh-feacckt oforsr1) Risk1) Monitoring of pos. DSI5) neg. pos. DSI5) neg.
n aneasthesia
ori depth:
Monit High risk Aavnoaieds ttohoe sdieae4)p Differential6) Aanddm diissscihoanrge Differential6) Every shift
Pre-aDsesteasislemdent6) Post-Dasestaesilsemdent6)
Treat underlying cause, if possible. Treat underlying cause, if possible.
py S.ymptom-orientated pharmacotherapy: .Symptom-orientated pharmacotherapy:
a Titrate haloperidol (0.25 mg-wise, Titrate haloperidol (0.25 mg-wise,
Ther . mUnesauexr oa3.ll5tee pmrtnigca)stively low dose atypic . mUnesauexr oa3.ll5tee pmrtnigca)stively low dose atypic
Algorithmforpre-operative,intra-operativeandpost-operativemanagementofpost-operativedeliriuminadultpatients.Thealgorithmshowsthe
differenttimestagesofsurgery(lefttoright)and,inadifferentaxis,preventive(top),diagnostic(middle)andtherapeutically(lower)actionsthat
shouldbetaken.Thered‘startbutton’helpstheusertostartatthefirststepinthedifferenttimestages.(1)Riskestimation(clinicalassessment
takingintoconsiderationpredisposingandprecipitatingriskfactors);riskfactorscanbefoundindetailintheguidelinerecommendation,
determinationofriskintoahighandalow-riskgroupcanbemadeasaclinicaldecision(2)Neuromonitoring(EEG/EMG-based)recommendedif
available;(3)DSI,DeliriumScreeningInstrument(shouldbevalidatedintheappliedlanguage);(4)nonpharmacologicalmeasurestoreduce
postoperativedeliriumshouldincludeorientation(clock,communication,etc.);visual/hearingaids;noisereductionandfacilitationofsleep;
avoidanceofuselessindwellingcatheters;earlymobilisation;earlynutrition;pharmacologicaltreatmentshouldbeinstitutedtoimprovepatientsafety
ifnonpharmacologicalmeasuresfail;(5)differentialincludestheassessmentandpossiblemodificationofunderlyingcausesfordelirium:use,for
example,the‘IWATCHDEATH’-acronym:Infectious(e.g.UTIandpneumonia);Withdrawal(e.g.alcohol,opioidsandbenzodiazepines);Acute
metabolicdisorder(electrolyteimbalanceandrenaldysfunction);trauma(operativetrauma);CNSpathology(e.g.strokeandperfusion);hypoxia(e.g.
anaemia,cardiacfailureandpulmonaryfailure);deficiencies(e.g.vitaminB12,folicacidandthiamine);endocrinepathologies(e.g.T3/T4and
glucose);acutevascular(e.g.hyper-/hypotension);toxins(e.g.anaesthetics,drugswithanticholinergicside-effects);heavymetals(rarecause);(6)
detailedpre/post-surgicalassessmentofcognitivefunctionwithvalidatedtools.EEG,Electroencephalograph;EMG,Electromyography;UTI,urinary
tractinfection;CNS,centralnervoussystem.
Eur J Anaesthesiol 2017; 34:192–214
200 Aldecoaetal.
Table8 Evidence-basedandconsensus-basedstatementsregardingpreventionandtreatment
Agegroup(inclusioncriteria)
Statement LoE Alladults >65years GoR
–
Wesuggestimplementingfast- [158],1b;[159],2b;[193],2b; [159,193] [158,194] B
tracksurgerytopreventPOD [193],2b
Wesuggestavoidingroutine [10],2b;[105],5;[195],2b; [10],Incl.none,PODþ, B
premedicationwith [196],3b;[197],NR;[198], 67.7years,POD(cid:6),50
benzodiazepinesexceptfor 2b;[204],2b years;[105,195,196],
patientswithsevereanxiety >60%were(cid:4)65years;
[197];[199]meanage
66.8yearsandrange
43–87years
Werecommendmonitoring [105],5;[199],1b;[200],1b; [199–201] [105,202] A
depthofanaesthesia [201],1b;[202],1b
Werecommendadequatepain [103],2b;[153],1b;[197], [202] [103,153,197,199,205] A
assessmentandtreatment NR;[203],4;[205],2b;
[206],(SR)
Wesuggestusingacontinuous [13],2b;[207],2b [13,207] B
intraoperativeanalgesia
regimen(e.g.with
remifentanil)
Werecommendpromptly [37],2b;[38],2b;[179],2b; [37] [38,179,208] A
diagnosingPOD, [208],Consensusreview
establishingadifferential
diagnosis,andinstituting
treatment
Wesuggestusinglow-dose [208],5;[209],SR;[210],2b; [208,209] [211,212] B
haloperidolaorlow-dose [211],2b
atypicalneurolepticstotreat
POD
Datapresentedasreferencenumber,LoE.Incl.inclusioncriteria;obsvd.,observed;LoE,levelofevidence;GoR,gradeofrecommendation(strong¼A,conditional¼B);
POD,postoperativedelirium.aLow-dosehaloperidolmeans0.25mgstepwisetitrateduptomaximumof3.5mg.213Anexcessivedoseofhaloperidolofmorethan6mga
dayshouldnotbeused.214Long-termuseindementiapatientsmayincreaseharm.215
Pharmacological premedication (in particular benzo- neuroleptics122,233,234reducetheincidenceofPOD231or
diazepines) is not always needed, and its routine use reduceitsseverityandduration,229thesefindingsremain
has been questioned.208 However, for highly anxious uncertain due to inconsistent results of aggregated evi-
patients or patients with alcohol or benzodiazepine use dence.232,235 Therefore, their routine use is currently
disorders, careful use of premedication for prevention not advisable.
and treatment can be considered.107,216,217
It remains unclear whether different regimens of anaes-
PreventionofPODinpatientswithalcoholusedisorders thesia influence the development of POD. Cohort
(e.g. measured by the Alcohol Use Disorders Identifi- studies, retrospective or secondary analyses185,236,237
cation Test (cid:4)8 points) may include long-acting benzo- and RCTs88,126,238–242 have shown mixed results and
diazepines, neuroleptics, a -agonists and alcohol.218 In do not imply a role in adults. However, an important
2
the subset of patients with alcohol withdrawal-induced factorinmanagingPODisadequatestressreductionwith
delirium,benzodiazepinesshouldbeoneofthefirst-line sufficient analgesia, an appropriate choice of analgesia
medications.105Assecond-linemedication,a -agonistsor and the use of intraoperative opioids.13,180 Currently, it
2
neuroleptics can be used. For emergence delirium, remainsunclearifintraoperativeadministrationofshort-
benzodiazepinesmightbea precipitatingfactor,48,107,219 acting analgesia impacts on POD. Some observational
although this remains controversial.180 dataareavailablesuggestingthatanalgesiaprovidedwith
continuous administration of remifentanil might reduce
Dataonmelatoninforpremedicationontheeveningbe- the incidence of POD compared with a bolus-driven
foresurgeryareinsufficienttodrawfinalconclusions,and regimen with fentanyl,207 but to draw convincing con-
currently no clear recommendation can be given.220–223 clusions, evidence from RCTs is required.
Perioperativea -agonists,forexampledexmedetomidine
2
To standardise the assessment and treatment of post-
orclonidine,mightbeconsideredtodecreasetheincidence
ofPODaftercardiacorvascularsurgery.224–228 operative pain, we refer to the American Society of
Anesthesiologists’ guideline on acute pain management
Thereareconflictingresultsregardingtheincidenceand in the perioperative setting.243 Although high preopera-
severity of POD through prophylactic administration of tive129 and postoperative pain244 are risk factors for
haloperidol35,229–231 or atypical neuroleptics.122,232–234 delirium, opioid analgesics may also be a risk factor
Although there is some evidence that preventive low- in respect of side effects and organ dysfunc-
dosehaloperidol35,229–231orpreventivelow-doseatypical tion.115,180,197,245,246 Patient-controlled analgesia (PCA)
Eur J Anaesthesiol 2017; 34:192–214
Evidenceandconsensus-basedguidelinesonpostoperativedelirium 201
could be one option if the patient is able to titrate the increases. Data provided by the WHO for Western
medicationandfindtherightbalancebetweenanalgesia Europe report a prevalence of 1.6% in patients aged
andtheminimumdoseofopioids.247PODdoesnotlimit 60 to 64 years and up to 43.1% in patients older than
PCAuse.247Regionalanaesthesiaandregionalanalgesia 90 years.259 Previous dementia,23,67,146 cognitive impair-
have not shown any benefit in respect of POD.248 ment11,12,15,18,34,71,90,93,108–110,113,115,116,125,169,260,261 and
depression20,22,71,91,110,112,123,143 are associated with
A healing environment should be considered for the
development of POD.
prevention of POD. Apart from the consensual state-
ments on nonpharmacological treatment, this should Other chronic diseases are often reported to be
be embedded in an environment for cognitive,249 func- present in more than 50% of patients aged 65 to
tional, social and emotional enhancement.250 Further 70 years. In 30% of these patients, more than
research is required to optimise the use of self-healing one single chronic disease is present. Cardiovascu-
competencies of patients. lar14,16,17,24,28,77,95,103,125,127,148,260,262 and meta-
bolic15,34,131,135,136 risk factors/diseases were found to
Special patient groups be most frequently associated with POD.
Geriatric patients
Multimorbidity consists of a situation in which clinical
A ‘threshold theory of cognitive decline’ was postulated
patterns, evolution and treatment become more compli-
toexplainasituationofdiminishedbrainreservecapacity
cated than the simple sum of the different illnesses.
occurring in older age, the genesis of which coincides
Multimorbidityreducesthecapabilitytocopewithstress
with the degenerative phenomena occurring with age-
andincreasesglobalvulnerability – includingtheriskfor
ing.251Duetothisreducedbraincapacity,olderpatients
POD.257,263 Functional status, also called the sixth vital
are on a ‘functional cliff’ for developing POD when
sign,isdefinedasthesumofbehavioursthatareneeded
undergoing a major physiological stress.
tomaintaindailyactivities,includingsocialandcognitive
InEurope,thepercentageofpeopleagedatleast65years functions.264 Impaired functional status (i.e. reduced
currently ranges from 12% in ‘young’ countries such as levels of independence, abilities and socialisation) is
Ireland to 21% in ‘old’ countries such as Germany and common among the elderly as a result of gait alteration,
Italy.252Withthepassageoftime,thiswillhaveamajor lossofcoordination,reducedorabolishedsphinctercon-
impactonthedemandforhealthcareservices,especially trol, malnutrition, associated illnesses and/or cognitive
surgery. There are higher rates per population of both deterioration. Impaired functional status is associated
inpatient and outpatient surgical and nonsurgical pro- withsurgicalsiteinfection,increasedmortalityandcom-
cedures among the elderly compared with other age plication rate. In the preoperative setting, performance
groups.253 Patients older than 80 years are the most measuressuchasthetimed‘Up&Go’Test265andother
rapidly increasing group among surgical admissions.254 forms of Comprehensive Geriatric Assessment266 have
InItaly,38%ofpatientswhoundergosurgeryareatleast often been used. Impaired functional status has been
65 years old.255 In the USA, approximately half of oper- reportedasapredisposingfactorforPOD.23,34,89,169,267–271
ations are performed in patients aged at least 65
The term ‘frailty’ indicates a situation of critically
years.254,256 Thus, the demand for surgery by older and
reduced functional reserves, involving multiple organ
sickerpatientsisincreasing,257andPODisregardedasa
systems. It manifests with impaired capability to cope
major problem.
with intrinsic and environmental stressors and limited
capability to maintain physiological and psychosocial
Risk factors and preoperative evaluation
homeostasis. Currently, 5.8 to 27.3% of the elderly
Ageinginvolvesacontinuumofchangesinbiologicaland
((cid:4)65 years of age) in the general European population
functional parameters that increase vulnerability and
are reported to be frail.272 However, studies examining
reduce functional reserve.258 Ageing is often accom-
olderpatientsundergoingelectivecardiacandnoncardiac
panied by chronic multiple diseases, disability and
surgery quote prevalences of frailty between 41.8 and
frailty.
50.3%273,274;thishighlightsthegreatvulnerabilityofthis
Althoughchronologicalageplaysaroleinpredisposingto patient age group. Hypoalbuminaemia, hypocholestero-
POD, it probably acts as a surrogate variable for the laemia and high levels of inflammation together with
accumulation of age-related risk factors that are differ- muscular atrophy are specific markers. Frailty has been
entially expressed among individuals; it is almost cer- foundtobeapredisposingfactorforPODamongelderly
tainlythesumoftheseriskfactorsthatismostimportant surgical patients.75,123,133,275
in determining the probability of POD.
Hearing loss was found to be a predisposing factor for
Dementia is a main predisposing factor for POD. POD in three studies276–278 and mentioned in three
Thisconditionisveryrareamongpatientsunder60years reviews58,270,279; the last two of these reviews and one
of age and becomes increasingly frequent as age additional study on internal medicine patients120
Eur J Anaesthesiol 2017; 34:192–214