Nederlandse Ziekenhuisfarmaciedagen, 26 en 27 mei 2011

Transcription

1 2011;5:1143 Nederlndse Ziekenhuisfrmciedgen, 26 en 27 mei 2011 Dit rtikel bevt de bstrcts vn de mondelinge presentties tijdens de Nederlndse Ziekenhuisfrmciedgen op 26 en 27 mei 2011 te Amersfoort. De digitle versie vn dit rtikel op pw.nl omvt ook de bstrcts vn de posterpresentties. 96 Phrmcodynmics of 5700 IU ndroprin subcutneous in morbidly obese ptients using nti-x levels Jeroen Diepstrten *, Esther J.H. Jnssen, Christin M. Hckeng, Simone vn Krlingen, Mrisk Y.M. Peeters, Eric P.A. vn Dongen, René J. Wiezer, Bert vn Rmshorst nd Ctherijne A.J. Knibbe St Antonius Hospitl, Nieuwegein. * Correspondence: j.diepstrten@ntoniusziekenhuis.nl. Morbidly obese ptients (BMI > 40 kg/m 2 ) re t incresed risk for thromboembolism, especilly fter surgery. Low-moleculrweight-heprins hve been shown to substntilly reduce this risk. However, if nd how the dose should be djusted with lrge increses in body weight is unknown. In clinicl prctice double dose of ndroprin for thrombosis prophylxis is often used for (morbidly) obese ptients with limited clinicl evidence. The primry im of this study ws to evlute the efficcy nd sfety of double dose of ndroprin (5700 IU) in morbidly obese ptients using nti-x levels, ultrsound nd occurrence of bleedings. Secondrily, we developed popultion phrmcodynmic (PD) model of ndroprin used for thrombotic prophylxis in morbidly obese ptients, thereby studying the influence of covrites. At induction of nesthesi for britric surgery, 5700 IU (= 0.6 ml) ndroprin ws dministered subcutneously. Chromogenic nti-x levels were mesured just before nd 10, 30, 60, 90, 120, 180, 240, 300 nd 420 minutes fter ndroprin injection nd the next morning within 24 hours fter dministrtion. Primrily, it ws evluted whether the recommended prophylctic rnge of IU/ml ws reched four hours fter dministrtion (C 4h ) while the AUC 0-24h nd the occurrence of thrombotic events (echo) nd bleedings were reported. Secondrily, popultion PD modelling ws performed using NONMEM VI. Twenty morbidly obese ptients were included with medin body weight of 144 kg (rnge kg) nd medin BMI of 51 kg/m 2 (rnge kg/m 2 ). Medin C 4h ws 0.21 IU/ml (SD 0.07), with ten ptients showing C 4h levels below the therpeutic rnge. Medin AUC 0-24h in morbidly obese ptients ws 2.80 h IU/ml (SD 0.97). No cliniclly reported, ultrsound-mesured thrombotic events or bleeding were observed. In two-comprtment phrmcodynmic disposition model with delyed bsorption, body weight (BW) proved to be the most predictive covrite for clernce [CL = 47.6 ml/min (BW/144) 1.5 ] while len body weight (LBW) ws the most predictive covrite for volume of distribution [V ss = 12.6 L (LBW/66) 1.5 ]. Upon double dose of ndroprin in morbidly obese ptients, nti-x concentrtions four hours fter dministrtion were below the therpeutic rnge in 50% of the ptients nd AUC 0-24h levels proved comprble to AUC 0-24h levels described for non-obese ptients fter single dose of 2850 IU ndroprin. The phrmcodynmics of ndroprin mesured using nti-x levels, re influenced by excessive body weight nd therefore n djusted dose seems necessry for morbidly obese ptients. Keywords: ndroprin nti-x morbid obesity ATTACK-study (interim nlysis): Allopurinol TretmenT And oxipurinol Concentrtions in gouty ptients: Knowing the therpeutic window D. Vogel *, M. vn de Lr bc, T. Jnsen d, C. Hgsm e, M. Reinders f, J.R.B.J. Brouwers g nd E.N. vn Roon Deprtment of Clinicl Phrmcy, Medisch Centrum Leeuwrden. b Deprtment of Rheumtology, Medisch Spectrum Twente, Enschede. c University Twente, Enschede. d Deprtment of Rheumtology, Universitir Medisch Centrum Nijmegen. e Deprtment of Rheumtology, Zorggroep Twente, Almelo/ Hengelo. f Deprtment of Clinicl Phrmcy, Atrium Medisch Centrum, Heerlen. g Deprtment of Phrmcotherpy nd Phrmceuticl Cre, University of Groningen. * Correspondence: d.vogel@znb.nl. Objective Allopurinol is proven effective in treting gout [1]. Nevertheless, only 25% of gouty ptients is successful in reching trget urte concentrtions [2, 3]. When urte lowering is insufficient llopurinol dosge should be rised until the mximum dosge of 900 mg per dy is reched [4]. The ctive metbolite of llopurinol is oxipurinol. The mrketing uthoriztion holder of llopurinol dvises to mesure the oxipurinol concentrtion in cse of impired renl function, where the oxipurinol concentrtion should be beneth 15.2 mg/l to void dverse effects [4]. Common prctice shows tht oxipurinol concentrtions re seldom mesured. In the pst yers severl uthors hve mde suggestions bout mesuring oxipurinol concentrtions in llopurinol- p w w e t e n s c h p p e l i j k p l t fo r m 2011;5(6)

2 2011;5:1143 treted ptients nd the therpeutic window tht should be pursued [5-7]. The objective of the ATTACK study is to investigte whether there is n ssocition between oxipurinol concentrtion nd the chnce of successful lowering of urte concentrtion in gouty ptients (defined s reching urte concentrtions < 0,30 mmol/l). An observtionl, prospective, multicenter study on gouty ptients, treted with llopurinol. Inclusion criteri were: gout dignosed with microscopic urte crystls, first tretment with llopurinol, completed informed consent. Exclusion criteri were: ge beneth 18 yers nd pregnncy, estimted GFR below 20 ml/min, ptients using zthioprine, mercptopurine or cyclophosphmide. Primry outcome mesures: ssocition between oxipurinol concentrtion nd the chnce of successful tretment of gout (defined s reching urte concentrtions of < 0.30 mmol/l). Ptients were seen by the rheumtologist fter two nd four months. Quntifiction of serum llopurinol nd oxipurinol ws performed by vlidted HPLC-UV method. Complince ws mesured with vlidted questionnire for gouty ptients. Sttisticl nlysis for the ssocition of serum oxipurinol concentrtions nd tretment success ws performed by using Receiver Operting Chrcteristic (ROC) in SPSS (18.0). 94 ptients were vilble for inclusion, of which 60 re evluble t this moment (80% mle). ROC nlyses of the results two months fter inclusion showed n AUC of 0,67 (P = 0.03). A cut-off vlue of oxipurinol ws found t 12.2 mg/l with sensitivity of 78%. The verge complince ws 74%. Averge urte lowering ws 0,23 mmol/l (bseline vs. first follow-up visit) nd 0,18 mmol/l (bseline vs. second follow-up visit). Oxipurinol concentrtion is ssocited with successful urte lowering in gouty ptients (P = 0,03) defined s reching serum urte < 0.30 mmol/l. Keywords: therpeutic drug monitoring gout llopurinol oxipurinol literture 1 Sutri et l. Effectiveness of interventions for the tretment of cute nd prevention of recurrent gout: systemtic review. Rheumtology 2006;45: Reinders MK. Prctice reserch in the field of gout, clinicl phrmcology of ntihyperuricemic drugs [disserttion]. Groningen: Rijksuniversiteit Groningen; Reinders et l. Efficcy nd tolerbility of urte-lowering drugs in gout: rndomised controlled tril of benzbromrone versus probenecid fter filure of llopurinol. Ann Rheum Dis. 2009;68(1): SPC, Zyloric llopurinol. 5 Hnde et l. Severe llopurinol toxicity. Description nd guidelines for prevention in ptients with renl insufficiency. Am J Med. 1984;76: Vázquez-Melldo et l. Reltion between dverse events ssocited with llopurinol nd renl function in ptients with gout. Ann Rheum Dis. 2001;60: Dlbeth et l. Dose djustment of llopurinol ccording to cretinine clernce does not provide dequte control of hyperuricemi in ptients with gout. J Rheumtol. 2006;33: Identifiction of drug-relted problems by clinicl phrmcist in ddition to computerized physicin order entry lerts Rinne J. Zl *, Mrk M.P.M. Jnsen bc, Mrjolijn Duisenbergvn Essenberg bc, Cees C. Tijssen c, Jn A. Roukem c nd Ptrici M.L.A. vn den Bemt Ersmus MC, Rotterdm. b TweeSteden Hospitl, Tilburg. c St Elisbeth Hospitl, Tilburg. * Correspondence: r.zl@ersmusmc.nl. Problems ssocited with phrmcotherpy occur frequently in hospitlized ptients nd cn result in ptient hrm nd incresed costs. Active prticiption of clinicl phrmcists on the wrd hs been shown to reduce drug-relted problems (DRPs, i.e. mediction errors nd dverse drug events) in different settings. Besides, implementtion of computerized physicin order entry systems together with clinicl decision support systems (CPOE/CDSS) hs the potentil to reduce DRPs, prticulrly mediction errors. However, the dded vlue of clinicl phrmcists compred to the identifiction of DRPs vi CPOE/CDSS is uncler. Therefore, this study ws performed to determine which DRPs identified by clinicl phrmcist would lso be detected by CPOE/CDSS. A clinicl phrmcist performed weekly mediction reviews to identify possible DRPs in ptients dmitted to two surgicl wrds nd two neurologicl wrds. For ech ptient, the relevnce of identified DRPs nd proposed ctions to meliorte them were discussed with the responsible physicin. Follow-up of the proposed ctions for relevnt DRPs s well s the presence of lerts in the CPOE/CDSS (Therik Mediction Mngement) were ssessed by the clinicl phrmcist. Primry outcomes were the possible nd relevnt DRPs identified by the clinicl phrmcist nd the number of DRPs tht generted n lert in the CPOE/CDSS. Secondry outcome ws the percentge of follow-up of the proposed ction. During 1206 mediction reviews, 445 possible DRPs were identified in 228 ptients; 289 DRPs (65%) were considered relevnt for the individul ptient nd 250 (87%) of the proposed ctions for these relevnt DRPs were completed. In totl 35 (8%) of the possible DRPs identified by the clinicl phrmcist resulted in CPOE/CDSS lert, of which 25 (71%) were considered relevnt. The proportion of relevnt DRPs mong DRPs detected by the clinicl phrmcists only nd DRPs lso detected by CPOE/CDSS did not differ (odds rtio 1.38; 95% confidence intervl ). The most common relevnt DRPs were unnecessry drug therpy (21%), requirement of dditionl drug therpy (14%) nd discrepncy with pre-dmission mediction (14%). Drugs frequently involved were those for the nervous system (25%), the crdiovsculr trct (14%), the blood system (13%) nd the gstro-intestinl trct (13%). 97 p w w e t e n s c h p p e l i j k p l t fo r m 2011;5(6)

3 2011;5: The mjority of DRPs identified by clinicl phrmcist ws not detected by CPOE/CDSS in dily phrmcy prctice. Therefore, clinicl phrmcist in ddition to CPOE/CDSS contributes to the reduction of DRPs. Besides, these results cn be used to optimize the sensitivity of CPOE/CDSS to identify DRPs. Keywords: clinicl phrmcist mediction errors dverse drug events computerized physicin order entry clinicl decision support system Nederlndse Ziekenhuisfrmciedgen, 26 en 27 mei PW Wetenschppelijk Pltform. 2011;5:1143. De digitle versie vn dit rtikel op pw.nl omvt ook de bstrcts vn de volgende posterpresentties Mediction sfety Electronic monitoring to ssess dherence nd vlidte lterntive dherence mesures in tuberculosis ptients on community-bsed Directly Observed Tretment The role of the phrmcist in geritric wrd rounds Development of n outptient, phrmcist-led group intervention to improve mediction dherence Assessment of the incidence nd nture of dverse drug events in surgicl ptients using new surgicl trigger tool Influence of brcode-ssisted mediction dministrtion on the rte of mediction dministrtion errors in surgicl wrd Effect of instruction mnuls on the documenttion of mediction chnges nd clinicl informtion by community phrmcies for dischrged ptients A new clinicl rule for identifying hyperklemi in ptients using potssium-influencing drugs Comprison of ntibiotic dosing recommendtions for neontes from estblished textbooks: pving the wy for e-prescribing stndrds Development of wrd-bsed phrmcy intervention strtegy to improve mediction sfety in surgicl ptients (prt of the SUREPILL study) The effect of mediction verifiction t hospitl dmission by phrmcy technicins on mediction discrepncies Alert ftigue bsent mong HIV specilists, but trust in lert texts low The ssocition between hospitlistion nd discontinuity of psychotropic drug use Frequency of lbortory mesurement nd hyperklemi in hospitlised ptients using serum potssium concentrtion incresing drugs Refill dherence with inhled corticosteroids in children with sthm nd the risk of sthm excerbtions Oncology nd phrmcogenetics Simvsttin sensitizes KRAS mutnt tumor cells for cetuximb nd pnitumumb Concordnce of predictive mrkers for EGFR inhibitors in primry tumors nd metstses in colorectl cncer Potentil drug interctions in cncer therpy: prevlence study using n dvnced screening method Popultion phrmcokinetics nd phrmcogenetics of everolimus in renl trnsplnt ptients on clcineurin inhibitor free regimen The PCSK9 E670G vrint nd reduced sttin effectiveness Pretrgeted immuno-pet imging nd rdioimmunotherpy of prostte cncer with n nti-egp1 nti-hsg bispecific ntibody Genetic risk fctors for type 2 dibetes mellitus nd response to sulfonylure tretment Phrmcogenetics: from bench to byte Phrmcokinetics nd phrmcodynmics Prevlence nd persistence of low infliximb serum trough levels in RA ptients with low disese ctivity in dily clinicl prctice Therpeutic drug monitoring of voriconzole is wrrnted in peditric ptients nd results in trget ttinment The Interntionl Interlbortory Qulity Control Progrm for Mesurement of Antiretrovirl Drugs in Plsm: globl proficiency testing progrm A comprison of the phrmcokinetics of rltegrvir during pregnncy nd post-prtum Therpeutic drug monitoring to improve sfety nd efficcy of posconzole in hemtology ptients Mitotne hs strong nd durble inducing effect on CYP3A4 ctivity Phrmcokinetics of efvirenz dosed ccording to the WHO weightbnds in children in Ugnd Ribvirin plsm concentrtions in chronic heptitis C infected ptients with or without HIV co-infection: is there difference? The effect of ritonvir on phrmcokinetics of tcrolimus in pretrnsplnt kidney filure ptients with HIV: the need for new trough levels? Popultion phrmcokinetic-phrmcodynmic nlysis of the ntihypertensive effect of eprosrtn Phrmcokinetics of orlly dministered urcil in helthy volunteers nd in DPD-deficient ptients, possible tool for screening for DPD deficiency Vrious Rndomized double-blind controlled tril of intrvenous morphine 2.5 mg versus 7.5 mg for procedurl pin in postopertive crdiothorcic ptients The effect of dily versus weekly folic cid supplementtion on the incidence of trnsminse elevtions in methotrexte-treted ptients with rheumtoid rthritis Influence of Phrmcotherpeutic Consulttion on the durtion nd chrcter of the rheumtologist s outptient consulttion Purple gstric juice discolortion in n infnt receiving omeprzole inctivtion of omeprzole due to premture coting dissolution The effect of preopertive erythropoietin protocol on llogeneic blood trnsfusions in dily clinicl prctice First EDI (GS1 stndrd) invoice implemented in Dutch helthcre Evidence-bsed choice of opioids in fril elderly ptients with chronic pin Long-term effects of meltonin on sleep nd qulity of life in hemodilysis ptients (Melody study) Sugmmdex compred to neostigmine does not decrese postopertive complictions Evlution of cspofungin tretment in dily prctice p w w e t e n s c h p p e l i j k p l t fo r m 2011;5(6)

4 2011;5:1143 Mediction sfety Electronic monitoring to ssess dherence nd vlidte lterntive dherence mesures in tuberculosis ptients on community-bsed Directly Observed Tretment Jossy vn den Boogrd, Rmsey Lyimo b, Mrtin J. Boeree, Gibson S. Kibiki b nd Rob E. Arnoutse * Rdboud University Nijmegen Medicl Centre, Nijmegen. b Kilimnjro Clinicl Reserch Institute t the Kilimnjro Christin Medicl Centre, Moshi, Tnzni. * Correspondence: r.rnoutse@kf.umcn.nl. ttendnce the highest specificity (80-100%) but lowest sensitivity (14-35%). The sensitivity of the routinely vilble combi ntion of pill counts nd clinic ttendnce improved when the ACTG questionnire ws dded. The high dherence rtes confirm tht community-bsed DOT cn be n effective strtegy to prevent non-dherence. The combintion of pill counts, refill visits nd ACTG questionnire is fesible method to monitor dherence when MEMS is not ffordble. Keywords: dherence tuberculosis community-bsed Directly Observed Tretment (DOT) Mediction Event Monitoring System (MEMS) Non-dherence to tuberculosis (TB) tretment is mjor obstcle to the control of this infectious disese. WHO s solution of Directly Observed Tretment (fcility-bsed DOT) is cusing overburdened helthcre fcilities worldwide. Involvement of community members in the provision of DOT is n lterntive, but dherence under community-bsed DOT is unknown nd this strtegy my need monitoring by dherence mesures. The objective of this study ws to ssess dherence rtes of TB ptients on community-bsed DOT by using the Mediction Event Monitoring System, bottle with chip in the cp (MEMS bottle), nd to determine the vlidity of other loclly fesible dherence mesures with MEMS s reference stndrd. This ws longitudinl study mong 50 dult TB outptients in Tnzni s Kilimnjro Region who were monitored by community-bsed DOT. Adherence to once-dily TB drugs ws ssessed throughout 6 months of TB tretment by using MEMS, urine test for isonizid, urine colour test for rifmpicin, the Morisky dherence scle, the Brief Mediction Questionnire (BMQ), n dpted version of the AIDS Clinicl Trils Group (ACTG) dherence questionnire, pill counts nd clinic ttendnce for mediction refills. MEMS dt were used to clculte dherence rtes by dividing the number of dys on which bottle opening ws registered by the number of monitored dys, multiplied by 100%. MEMS dherence rte cut-off vlues of 100% nd 95% were used to differentite between dherence nd non-dherence. The sensitivity nd specificity to detect non-dherence s ssessed by MEMS ws clculted for the other (combintion of) dherence mesures. 50 ptients were enrolled; 37 completed tretment, 6 died, 3 de - fulted nd 4 dropped out. Adherence rtes rnged from 50 to 100% (medin 98%) in ll ptients, nd from 89 to 100% (medin 98%) in the ptients who completed tretment. In the ltter group, 70% of ptients were less thn 100% dherent nd 19% less thn 95%. The ACTG questionnire nd urine colour test hd the highest sensitivity (70-100%) but lowest specificity (20-37%) for detecting non-dherence, nd the Morisky scle nd clinic The role of the phrmcist in geritric wrd rounds M.L. Becker *, T. vn der Cmmen b nd P.M.L.A. vn den Bemt Deprtment of Hospitl Phrmcy, Ersmus MC, Rotterdm. b Deprtment of Internl Medicine, Ersmus MC, Rotterdm. * Correspondence: m.becker@ersmusmc.nl. Introduction Adverse drug events (ADE) re responsible for substntil prt of the hospitl dmissions nd for prolongtion of hospitl stys [1, 2]. The hospitl phrmcist cn help in preventing these ADEs. A lrge number of studies in severl settings confirms this role [3, 4]. In this study, we ssessed how mny mediction-relted problems were identified nd intervened by (resident) hospitl phrmcist during wrd rounds on geritric wrd in n cdemic hospitl. In the period between Jnury 2009 nd December 2010, resident hospitl phrmcist prticipted regulrly in the weekly geritric wrd rounds. He screened the mediction prior to the wrd rounds for mediction-relted problems. During the geritric wrd rounds ll ptients nd their mediction were discussed with the geritricins, resident geritricins, nurses nd in some cses psychitrist, nd, if pplicble, suggestions were given to chnge the mediction. During the study period ll suggestions nd the chnges in mediction were recorded. During the study period, 49 wrd rounds were ttended nd 302 ptients were discussed (verge 6.2, rnge 3-9 ptients). 242 of these 302 ptients were newly dmitted. The verge ptient ws 82 yers of ge (rnge ) nd used 7.8 drugs (rnge 0-18). In totl, 93 suggestions were given to chnge the mediction. 60 suggestions (65%) resulted in mediction chnge. More interventions were done in ptients using more drugs (P = 0.015), but no ssocition ws found with the ge of the ptients (P = 0.37). 19 suggestions involved switching to nother drug, nd

5 2011;5: suggestions were to stop mediction, most often to prevent dverse drug rections. The other 23 suggestions were to strt mediction (n = 7), to chnge the dose (n = 6), to chnge the dose regimen (n = 6), or to use nother preprtion (n = 4). 33 suggestions were not ccepted by the physicins. The type of intervention did not differ between the ccepted nd the non-ccepted suggestions (P = 0.66). Resons for not chnging the mediction were tht clinicl reson to continue the mediction ws present (n = 14) or not knowing the indiction or the prescriber of the drugs (n = 10). Discussion One wy to void ADEs my be to regulrly screen the mediction of hospitlized ptients by phrmcist. The wrd rounds re good opportunity to do so. In this study, we found tht phrmcist could intervene in the mediction of one in four ptients tht were hospitlized on geritric wrd. references 1 Leendertse et l. Frequency of nd risk fctors for preventble mediction-relted hospitl dmissions in the Netherlnds. Arch Intern Med. 2008;168: Rudolph et l. The nticholinergic risk scle nd nticholinergic effects in older persons. Arch Intern Med. 2008;168: Gillepsie et l. A comprehensive phrmcist intervention to reduce morbidity in ptients 80 yers or older. Arch Intern Med. 2009;169: Fertlemn et l. Improving mediction mngement for ptients: the effect of phrmcist on post-dmission wrd rounds. Qul Sf Helth Cre. 2005;14(3): Keywords: mediction review dverse drug events geritrics Development of n outptient, phrmcistled group intervention to improve mediction dherence H. Zwikker, B.J.F. vn den Bemt b *, C.H.M. vn den Ende, A.A. den Broeder, H.B. Benrd b, A.M. vn Dulmen c nd F.H.J. vn den Hoogen b Deprtment of Rheumtology; b Deprtment of Phrmcy; Sint Mrtenskliniek, Nijmegen. c NIVEL, Utrecht. * Correspondence: b.vndenbemt@mrtenskliniek.nl. Almost 50 % of prescribed mediction in chronic conditions is not tken s directed. Improving dherence could therefore improve the efficcy of medicl tretments. However, interventions to improve dherence re s yet not very effective. An explntion for the limited success of existing interventions is tht most interventions ttempt to overcome unintentionl non-dherence (e.g. by issuing reminders or cler instructions), but fil to trget the beliefs bout mediction tht my led to intentionl non-dherence. Therefore, short ptient-centered group intervention ws developed trgeting individul s beliefs bout mediction nd, if necessry, prcticl brriers for dherence. The development of the group intervention consisted of three steps: (1) choice of theoreticl model on which the intervention will be bsed, (2) development of the intervention method, nd furthermore piloting the intervention in (3) ptient pnel, n expert pnel nd finlly s pilot intervention. Theoreticl model. The intervention is bsed on simplified I-Chnge model, suggesting tht individuls will dhere with helth regimens if they regrd themselves s hving been or being susceptible to the condition in question, if the condition hs serious current or future consequences, if the ction would be beneficil, nd if they feel tht brriers to ction re outweighed by the benefits. Ptients consider whether their beliefs bout the necessity of mediction outweigh their concerns bout potentil dverse effects of tking them. Thus, besides prcticl brriers like forgetfulness, clinicins should lso be sensitive to personl beliefs tht my impct mediction dherence. Intervention method. In order to trget the complex nd individul decision mking process in mediction dherence Motivtionl Interviewing (MI) will be used s method to chnge beliefs nd behviour. MI-bsed interventions to improve mediction dherence hve been studied before in ptients with chronic diseses nd there re some indictions tht these interventions re effective to improve mediction dherence. The intervention only included non-dherent ptients [mesured with the complince questionnire on rheumtology (CQR)]. Pilot. After the development phse, the intervention ws reviewed by n expert pnel consisting of psychologists, n MI expert, rheumtologists, (hospitl) phrmcists nd ptients. Finlly, two pilot interventions (12 ptients) were executed. The results of the expert review combined with video tpes of the pilot interventions were used s input for the optimiztion of the dherence intervention. A short motivtionl ptient-centred intervention ddressing the primry cuses of non-dherence in non-dherent ptients is successfully developed. Currently the effectiveness of this intervention is tested in rndomised clinicl tril in 100 nondherent ptients with rheumtoid rthritis. Keywords: dherence rheumtoid rthritis beliefs intervention

6 2011;5:1143 Assessment of the incidence nd nture of dverse drug events in surgicl ptients using new surgicl trigger tool M. de Boer *, E.B. Boeker b, J.J.S. Kiewiet b, M.A. Rmrttn, P.F.M. Kuks, W.M.C. Mulder c, P.J. Breslu d, R.J. Oostenbroek e, M.A. Boermeester b, L. Lie-A-Huen Deprtment of Hospitl Phrmcy, Acdemic Medicl Centre, Amsterdm. processes on medicl wrds. The effect of this pproch on pade incidence is now being crefully scrutinized in rndomised controlled tril (NTR2258). Keywords: preventble dverse drug events trigger tool cuslity ssessment surgicl ptient b Deprtment of Surgery, Acdemic Medicl Centre, Amsterdm. c Deprtment of Clinicl Phrmcology, Acdemic Medicl Centre, Amsterdm. d Surgeon, The Hgue. e Deprtment of Surgery, Albert Schweitzer Hospitl, Dordrecht. * Correspondence: m.deboer@mc.nl. Hrm cused by mediction errors, i.e. preventble dverse drug events (pades), re still problem in hospitls. Severl studies reported pade incidences between 0.6 nd 16%. Even in hospitls using computerized physicin order entry (CPOE) systems, pades still occur. Furthermore, the helthcre process of surgicl ptients differs gretly from other ptients. Until now, the incidence nd nture of pades in the surgicl popultion hs not been determined. The im of this study ws to quntify preventble ADEs in Dutch surgicl popultion of hospitls, where CPOE with clinicl decision support (CDS) is well implemented. In this observtionl cohort study, eight surgicl units in three different hospitls prticipted. Elective surgicl ptients with hospitl sty longer thn 48 hours were included. The units contined minly gstro-intestinl nd vsculr surgery ptients. To pre-select medicl records with potentil ADEs, trigger tool ws developed. This tool ws bsed on current literture s well s qulity indictors of good helthcre nd ws djusted to the surgicl popultion. The finl cuslity, severity nd preventbility of the detected ADEs, were ssessed by n independent expert pnel of surgeons nd clinicl phrmcologists. The medicl records of 567 prospectively included ptients were screened using the surgicl trigger tool. 340 medicl records contined one or more triggers for potentil ADEs nd were evluted by the expert pnel. This pnel found 28.2 ADEs per 100 dmissions of which 15.6% ws judged s preventble. Thus, the incidence of preventble ADEs ws 4.4 per 100 dmissions. Of these pades, 24% ws clssified s severe or life-thretening. In the surgicl popultion of three different Dutch hospitls using CPOE with CDS, totl incidence of 4.4 preventble ADEs per 100 dmissions ws found, of which considerble proportion ws clssified s severe or life-thretening. To improve mediction sfety, n intervention strtegy to reduce this incidence of preventble ADEs is proposed, the so-clled wrd-bsed phrmcy cre pproch. Phrmcy technicins nd clinicl phrmcists ctively prticipte in the clinicl decision-mking nd executive Influence of brcode-ssisted mediction dministrtion on the rte of mediction dministrtion errors in surgicl wrd J.J.M. Hssink *, M. Duisenberg-vn Essenberg nd P.M.L.A. vn den Bemt bc Deprtment of Hospitl Phrmcy, TweeSteden Hospitl nd St Elisbeth Hospitl, Tilburg. b Division Phrmcoepidemiology & Clinicl Phrmcology, Fculty of Science, Utrecht Institute for Phrmceuticl Sciences, Utrecht University. c Deprtment of Hospitl Phrmcy, Ersmus Medicl Center, Rotterdm. * Correspondence: jhssink@tsz.nl. In recent yers informtion technology hs become importnt in preventing mediction errors. For exmple, computerized physicin order entry systems re used to reduce prescription errors. Mediction dministrtion errors (MAEs) re nother importnt ctegory of mediction errors becuse they re seldom perceived nd they re irreversible. Brcode-ssisted mediction dministrtion (BCMA) is seen s promising tool in the prevention of this type of error. Up to now, few studies hve investigted the influence of BCMA on the mediction dministrtion error rte nd therefore we conducted the present study. Nurses on surgicl wrd were observed during five-dy period one week before nd six months fter implementtion of BCMA, using the disguised observtion technique. MAEs were counted s primry outcome. Besides BCMA new logistic procedure ws implemented comprising thrice dily supply of drugs from the hospitl phrmcy to the wrd insted of once dily. MAEs were ctegorized in: wrong ptient, wrong drug, unuthorized drug, wrong dose, wrong route, wrong time, omission nd omission due to bsence of the drug on the wrd (logistic omission). Two phrmcists independently clssified the severity of the observed errors using the Ntionl Coordinting Council for Mediction Error Reporting nd Prevention txonomy of mediction errors. In cse of initil differences in clssifiction consensus ws reched. The distribution of MAEs in clsses of severity ws scored s secondry outcome. The difference in occurrence of MAEs before nd fter implementtion of BCMA ws nlysed using univrite nd multivrite logistic regression nlysis. A chi-squre test ws used to test differences in MAE clsses of severity.

7 2011;5:1143 The observed number of mediction dministrtions before implementtion of BCMA ws 945 nd fter implementtion Prior to implementtion 68 MAEs including time errors (7.2%) were observed nd excluding time errors 28 (3.0%). After implementtion including nd excluding time errors respectively 36 (3.6%) nd 4 (0.4%) MAEs were seen. This corresponds to odds rtios (OR) of 0.48 (CI ) nd 0.13 (CI ) including nd excluding time errors, respectively. Adjusted ORs were 0.63 (CI ) nd 0.12 (CI ) respectively (ge ws included in the multivrite model). MAEs prior to implementtion of BCMA were ctegorized in clss C 79.4% nd D 20.6% nd fter implementtion in clss C 88.9% nd D 11.1% (OR 0.48; CI ). Mediction dministrtion errors re considerbly reduced using brcode-ssisted mediction dministrtion. No severe MAEs occurred during the observtion period nd no difference in distribution in ctegories of severity ws seen fter implementtion of BCMA. Keywords: mediction dministrtion errors brcode-ssisted mediction dministrtion Effect of instruction mnuls on the documenttion of mediction chnges nd clinicl informtion by community phrmcies for dischrged ptients F. Krpinr b *, R.L. vn Breukelen c, S.D. Borgsteede d, M.J.A. Jnssen, A.C.G. Egberts be nd P.M.L.A. vn den Bemt bf Deprtment of clinicl phrmcy, Sint Lucs Andres Hospitl, Amsterdm. b Division Phrmcoepidemiology & Clinicl Phrmcology, Fculty of Science, Utrecht Institute for Phrmceuticl Sciences, Utrecht University. c Science & Business Mngement (student), Utrecht University. d Gezondheidscentr Mrssenbroek, Mrssen. e Deprtment of clinicl phrmcy, University Medicl Centre Utrecht. f Deprtment of clinicl phrmcy, Ersmus Medicl Centre, Rotterdm. * Correspondence: f.krpinr@slz.nl. The St Lucs Andres Hospitl (SLAZ) sends dischrge mediction overviews (contining resons for mediction chnges/clinicl informtion) to community phrmcies to improve continuity of cre. However, community phrmcies do not lwys document the new informtion in their phrmcy records, which my hmper mediction surveillnce nd thus ptient sfety. The im of this study ws to evlute whether the documenttion of informtion on the dischrge mediction overview improved fter introducing instruction mnuls. A before-fter study ws performed (July 2009-August 2010). Ptients who were dischrged home from the crdiology/pulmonology wrd with dischrge mediction overview tht contined chnge in predmission mediction nd/or clinicl informtion were included. The intervention consisted of fxing the dischrge mediction overview together with the instruction mnul. This mnul specified how community phrmcies could document the informtion in their phrmceuticl dossier. Usul cre consisted of fxing only the overview. Two weeks fter dischrge, mediction records of the community phrmcies were requested by fx. These records were compred with the originl dischrge mediction overviews regrding the documenttion of llergies/ contr-indictions nd mediction chnges. For mediction chnges the community phrmcy s documenttion should clrify tht dose hd incresed/decresed (dose chnge), mediction hd been replced (switch) or tht mediction should not be prescribed nymore (discontinued mediction). Independent t-tests were used for continuous vribles nd chi-squre tests for proportions. In the study 218 ptients (112 before, 106 fter intervention) were included. There were no significnt differences between groups (ge, sex, number of mediction chnges/clinicl informtion). Documenttion of contr-indiction (35% before vs. 29% fter intervention, P = 0.678) nd correct documenttion of switched mediction (19% vs. 23%, P = 0.728) ws not different fter the intervention. Allergy documenttion improved non-significntly (54% before vs. 82% fter, P = 0.057). Dose chnges (1.4% vs. 8.6%, P = 0.006) nd discontinued predmission mediction (5.8% vs. 28%, P < 0.001) were documented significntly more frequently in the intervention period. The instruction mnuls led to n incresed documenttion of the dischrge mediction overview informtion. However, the frequency of incorrect/incomplete documenttion remins high: more thn 90% of the dose chnges nd more thn 80% of the discontinued mediction ws documented incorrectly by community phrmcies. Fxing n instruction mnul is insufficient to improve the qulity of informtion trnsfer between hospitl nd community phrmcies. Keywords: hospitl dischrge mediction errors communiction nd documenttion informtion trnsfer continuity of cre

8 2011;5:1143 A new clinicl rule for identifying hyperklemi in ptients using potssium-influencing drugs M.A. Kuijvenhoven *, E.A.F. Hk, K.B. Gombert-Hndoko nd M. Crul Deprtment of clinicl phrmcy, Onze Lieve Vrouwe Gsthuis, Amsterdm. * Correspondence: kuijvenhoven.m@znsmc.nl. Decresed renl function lredy strting from n egfr < 50 ml/min ws identified s sttisticlly significnt risk fctor for hyperklemi in ptients using potssium-influencing drugs. None of the other risk fctors were identified s significnt. In previous studies n egfr < 30 ml/min ws considered s threshold below which development of hyperklemi substntilly increses, however, our study observed threshold of egfr < 50 ml/min. This result provides specific clinicl rule tht will help to predict the risk of developing hyperklemi in ptients using combintion of potssium-influencing drugs. Keywords: hyperklemi potssium potssium-spring diuretics potssium supplements renin-ngiotensin-dosterone system (RAAS) inhibitors drug-drug interction In clinicl prctice potssium disorders re common, nd potentilly dngerous, electrolyte bnormlity. Reported incidence of hyperklemi in hospitls is 1% to 10%. It is known tht ptients using combintion of potssium supplements nd potssium-spring diuretics or renin-ngiotensin-ldosteronesystem (RAAS) inhibitors re especilly t risk. Previous studies on the incidence of hyperklemi in ptients with concurrent use of two or more potssium-influencing drugs were either smll in smple size or did not investigte the full rnge of drugs involved. In this study we explored the occurrence of hyperklemi in lrge cohort of ptients using potssium-influencing drugs. Also, we studied the role of other potentil risk fctors for hyperklemi. Objective To mesure the incidence of hyperklemi nd to identify risk fctors for hyperklemi in hospitlised ptients using potssium supplements, potssium-spring diuretics nd RAAS inhibitors concurrently. A retrospective, nested cse control study ws executed. Hospitlised ptients using combintion of potssium supplements nd RAAS inhibitors or potssium-spring diuretics were included in the study. Cses were defined s ptients with serum potssium norml serum potssium levels. Cses nd controls were included in rtio of 1:2. Known risk fctors ssocited with hyperklemi (dibetes mellitus, congestive hert filure, renl function, dvnced ge, gender, the use of heprin, digoxin, NSAIDs, bet-blocker, clcineurin ntgonists nd trimethoprim) were recorded nd sttisticlly nlysed. Of 774 ptients included in this study, 52 ptients developed hyperklemi; n incidence of 6.7%. From the studied risk fctors, only lowered renl function expressed s n estimted glomerulr filtrtion rte (egfr) < 50 ml/min ws significntly ssocited with hyperklemi (OR 5.08; CI ). Comprison of ntibiotic dosing recommendtions for neontes from estblished textbooks: pving the wy for e-prescribing stndrds T.B.Y. Liem *, T.G. Krediet b, A. Fleer c, A.C.G. Egberts nd C.M.A. Rdemker Deprtment of Clinicl Phrmcy; b Deprtment of Neontology; c Eijkmn- Winkler Centre for Microbiology, Infectious Diseses nd Inflmmtion; University Medicl Centre Utrecht, Wilhelmin Children s Hospitl, Utrecht. * Correspondence: y.liem@umcutrecht.nl. Incorrect dosing is the most frequently occurring prescribing error in peditrics nd ntibiotics re the most frequently prescribed medicines. Computer physicin order entry (CPOE) nd clinicl decision support systems cn contribute to the reduction of mediction errors. Although evidence-bsed dosing recommendtions should be included in such systems, the necessry evidence is not lwys vilble nd subsequently dosing recommendtions mentioned in guidelines nd textbooks re often bsed on expert opinion. The im of this study is to compre dosge recommendtions for ntibiotics in neontes provided by seven commonly used nd well-estblished interntionl textbooks. Neontl dily doses for the 10 most frequently used ntibiotics, clssified by ctegories for birth weight nd gesttionl ge, were identified from 7 well-respected textbooks in peditrics/ peditric infectious diseses, nd expressed s stndrdized verge dily dosge. Antibiotics with wide therpeutic window (e.g. mpicillin, benzylpenicillin, ceftzidime nd cefotxime) showed greter vrition in dosge recommendtions compred to those with smll therpeutic window (e.g. meropenem, gentmicin nd vncomycin). The BNF showed lrger vrition in dosge recommendtions compred to the other textbooks. Gold stndrd, expert opinion ntibiotic dosge recommendtions for neontes cn be derived from importnt textbooks nd guidelines for most, but not ll ntibiotics. Further explortion to

9 2011;5:1143 overcome vrition in dosge recommendtions is necessry to obtin stndrdized dosge regimens nd thus full benefit of CPOE nd clinicl decision support systems in neontology. Keywords: ntibiotics dosing neontes Development of wrd-bsed phrmcy intervention strtegy to improve mediction sfety in surgicl ptients (prt of the SUREPILL study) M.A. Rmrttn *, M. de Boer, E. Boeker b, K.B. Gombert- Hndoko c, N.A.E.M. vn Lent-Evers d, P.F.M. Kuks, M.A. Boermeester b nd L. Lie-A-Huen Deprtment of Hospitl Phrmcy, Acdemic Medicl Centre, Amsterdm. b Deprtment of Surgery, Acdemic Medicl Centre, Amsterdm. c Deprtment of Hospitl Phrmcy, Onze Lieve Vrouwe Gsthuis, Amsterdm. d Deprtment of Hospitl Phrmcy, Dikonessenhuis, Utrecht. * Correspondence: m..rmrttn@mc.uv.nl. ptient, the Action needed to prevent the dverse event, the Type of intervention, the Rection to nd Acceptnce of the intervention by the physicin, possible Follow-up ctions to monitor the problem nd informtion on the Intervener nd the Dte nd time of intervention. The types of potentil problems such s mediction-relted strtegies to prevent infections, thrombo-embolic complictions, nuse/vomiting in surgicl ptients nd relted clinicl interventions were preclssified. The intervention strtegy resulted in uniform working structure for the clinicl phrmcists in which clinicl phrmcists nd phrmcy technicins become well integrted in the dily routine of multidisciplinry cre tems on surgicl wrd. We developed wrd-bsed phrmcy intervention strtegy to improve mediction sfety in surgicl ptients nd implemented this strtegy in dily clinicl prctice. The effect of this pproch on pade incidence is now being crefully scrutinized in rndomised controlled tril (NTR2258). Keywords: dverse drug events wrd-bsed phrmcy surgicl intervention Adverse events cused by mediction errors (preventble dverse drug events, pades) still constitute n importnt cuse of morbidity nd mortlity, even in hospitls using computerized mediction order entry providing decision support. Mny studies hve demonstrted tht clinicl phrmcists nd phrmcy technicins cn reduce pades by prticipting in the clinicl decision-mking nd executive processes on medicl wrds. In this study, we describe the development nd implementtion of wrd-bsed phrmcy intervention strtegy to improve mediction sfety in surgicl ptients. To develop the intervention strtegy of wrd-bsed phrmcy, we used literture nd evidence-bsed guidelines to determine the criticl steps in the mediction process nd to define clinicl interventions relted to specific types of problems in surgicl ptients. We recently implemented this strtegy nd we re currently ssessing its effect in prospective controlled study with rndomistion t wrd level by mesuring the number of pades (SUREPILL study). We developed structured nd uniform method consisting of steps tilored to the clinicl process. Firstly, t dmission nd dischrge, mediction reconcilition with the ptient is performed by phrmcy technicins. During hospitl sty, clinicl phrmcists dily intervene in the ptients phrmcotherpy in liison with wrd doctors. To execute nd record these intervention steps, the cronym TREATRAFID is used. The TREATRAFID worksheet identifies the Type of problem by nlyzing the ptients mediction nd clinicl sttus, describing the Reson for intervention, the Evlution of the problem nd the risks incurred by the The effect of mediction verifiction t hospitl dmission by phrmcy technicins on mediction discrepncies Anneliene M. Schimmel *, Pierre M. Bet, José Tmming nd Jcqueline G. Hugtenburg Deprtment of Clinicl Phrmcology nd Phrmcy, VU Medicl Center, Amsterdm. * Correspondence:.schimmel@vumc.nl. Ptient trnsitions in cre re source of discrepncies between pre-dmission nd dmission mediction. Some discrepncies re unintended nd re the result of errors tht re potentilly hrmful for ptients. A mediction interview with the ptient by phrmcy technicin t dmission my reduce the frequency of mediction discrepncies. We therefore studied the effect of mediction verifiction by phrmcy technicins t hospitl dmission on the frequency nd nture of intended nd unintended mediction discrepncies between pre-dmission nd dmission mediction. An intervention study with pre-test/post-test design ws performed t the VU Medicl Center in Amsterdm. Ptients who were scheduled for elective surgery nd were using five or more chronic predmission medicines were included in the study t dmission to chirurgicl wrd. In the pre-test period, the drug regimen of ptients ws verified by n nesthesiologist during the preopertive screening nd by nurse nd physicin t dmission. The

10 2011;5:1143 intervention ws the introduction of mediction interview with the ptient t dmission by phrmcy technicin. The mediction prescribed on the first dy of dmission ws compred with the pre-dmission mediction. Intended nd unintended discrepncies were identified fter checking the ptient documenttion. Unintended discrepncies were clssified into four ctegories: omission of mediction, ddition of mediction, chnge in dosge or chnge in dosge form. The primry outcome ws the effect of the intervention on totl, intended nd unintended discrepncies. The secondry outcome ws the frequency of different types of unintended discrepncies. 67 ptients were included in the pre-test period (men ge 65 yers, 54% men, men number of predmission medicines per ptient 8.4) nd 68 ptients were included in the post-test period (men ge 63 yers, 53% men, men number of predmission medicines per ptient 9.1). The frequencies of mediction discrepncies per ptient before nd fter the intervention were respectively 8.1 nd 8.4 (P = 0.57), divided in 5.6 intended discrepncies before nd 8.2 fter the intervention (P < 0.001) nd 2.4 unintended discrepncies before nd 0.3 fter the intervention (P < 0.001). Addition of mediction nd chnge in dosge were the min types of unintended mediction discrepncies which were identified less frequently in the post-test period. The introduction of mediction verifiction by phrmcy technicins t hospitl dmission does not chnge the frequency of totl discrepncies per ptient between pre-dmission nd dmission mediction. However, the introduced mediction interview results in decrese of unintended nd n increse of intended mediction discrepncies. Keywords: mediction t dmission mediction discrepncies phrmceuticl cre drug sfety Alert ftigue bsent mong HIV specilists, but trust in lert texts low Heleen vn der Sijs *, Abdelilh el Brzouhi b nd Jos Arts Deprtment of Hospitl Phrmcy, Ersmus University Medicl Center, Rotterdm. b Institute of Helth Policy nd Mngement, Ersmus University, Rotterdm. * Correspondence: i.vndersijs@ersmusmc.nl. Physicins treting ptients infected with humn immunodeficiency virus (HIV) encounter mny drug sfety lerts, becuse of numerous drug drug interctions (DDIs) in highly ctive ntiretrovirl therpy (HAART) nd hve limited time becuse of treting ptients in outptient clinics. However, resistnce due to low drug serum levels cused by DDIs is serious problem to be prevented. The im of this study is to investigte how medicl HIV specilists hndle DDIs in the outptient clinic. All HIV specilists of Ersmus MC were invited for semi-structured interview with open questions, propositions, nd ptient cses. All 9 HIV specilists greed to prticipte. They were wrned often by the CPOE for DDIs they lredy knew. They ll prepred their consulting hours by looking up potentil DDIs in the booklet DDIs with ntiretrovirl drugs by Dvid Burger, nd the websites nd They trust nd vlue these informtion sources more thn the CPOE lerts, bsed on Burger s booklet, tht do not provide severity nd evidence levels nd lck references nd informtion whether texts re updted regulrly. They perceive the lerts s n extr check nd lwys look t the lert texts t lest slightly. This is followed by more thorough reding of the text if DDIs re unexpected or unknown, in cse of comorbidity (e.g. renl filure), in DDIs tht lower HAART serum levels, nd in long courses (e.g. tuberculosis tretment). DDI lerts re generlly overridden fter weighing risks nd benefits. Short-term rise of HAART serum levels is often ccepted. Toxicity tht cn be monitored is mentioned s n importnt override reson nd severl DDIs re consciously prescribed for cost effectiveness. Serum level lowering combintions perceived cliniclly relevnt re prevented by dose djustments or lterntive drug prescribing. All respondents showed thorough DDI knowledge in the ptient cses presented. HIV specilists do not suffer from lert ftigue nd perceive DDI lerts s n extr check fter they hve prepred their consulting hours with other informtion sources tht they trust nd vlue more. The physicins need severity nd evidence index, literture references, nd informtion on updtes to weigh benefits nd risks nd this informtion is bsent in the lert texts. Keywords: computerized physicin order entry CPOE drug sfety lerting drug-drug interctions humn immunodeficiency virus HIV Computerized physicin order entry (CPOE) with drug sfety lerting is n importnt mesure to improve mediction sfety. However, lert ftigue resulting from unspecific lerts consuming too much time nd energy, cn cuse relevnt lerts to be unjustifibly overridden long with cliniclly irrelevnt ones.

11 2011;5:1143 The ssocition between hospitlistion nd discontinuity of psychotropic drug use Rutger Stuffken b *, Eibert R. Heerdink, Ptrick C. Souverein nd Toine C.G. Egberts c Utrecht University, Fculty of Science, Utrecht Institute for Phrmceuticl Sciences, Division Phrmcoepidemiology nd Clinicl Phrmcology, Utrecht. b Tergooi Hospitls, Deprtment of Clinicl Phrmcy, Blricum/Hilversum. c University Medicl Center Utrecht, Deprtment of Clinicl Phrmcy, Utrecht. * Correspondence: rstuffken@tergooiziekenhuizen.nl. Ptients receive cre cross different helthcre settings. A hospitlistion is n importnt event t which ptients re t incresed risk of discontinuity of mediction use. Especilly mediction unrelted to the reson of hospitlistion my be t incresed risk of discontinution. In this study we test this hypothesis. Objective To ssess the ssocition between hospitlistion nd discont i- nuity of psychotropic drug use in ptients hospitlised for non-psychitric disese. For this retrospective follow-up study 10,000 hospitlistions between 1 July 1998 nd 30 June 2000 were rndomly selected (index ptients) from the Dutch PHARMO dtbse, s well s 10,000 non-hospitlised controls, mtched on region, ge nd gender. The controls were ssigned the sme index dte s the hospitlistion dte in the corresponding index ptients. Ptients who were dmitted for mentl disorders (ICD-9-CM code ) were excluded. Three mutully exclusive types of tretment discontinuities were defined: generic/brnd/product substitution, therpeutic switch nd stop. The primry study outcome ws the incidence of one or more mediction therpy discontinuities of psychotropic drugs t the index dte nd t severl control moments during period of 18 months before nd 18 months fter the index dte. The represcription rte for the sme phrmcotherpeutic group ws estimted in the time window of 4-12 months fter the index dte. The study popultion comprised 8,555 hospitlized ptients nd n equl number of controls. Of the 497 hospitlised ptients using psychotropic drug therpy t the index dte 30.6% hd mediction therpy discontinuity of psychotropic drugs, predominntly stops (n = 132, 26.6%). Of the 325 controls using psychotropic drug therpy t the index dte, 49 (15.1%) hd ny type of discontinuity (RR 2.03; CI ) The highest risk estimte ws found for stop (RR 2.54; CI ), followed by therpeutic switch (RR 1.09) nd generic/brnd/product substitution (RR 0.73). The represcription rte ws 23.5% for the hospitlised group of ptients. Ptients dmitted to the hospitl for non-psychitric disese nd while using psychotropic mediction re t incresed risk for stopping these psychotropic mediction. This rte of represcription indictes tht prt of stopped drug therpies cn be unintended stops. references 1 Glintborg B, Andersen SE, Dlhoff K. Insufficient communiction bout mediction use t the interfce between hospitl nd primry cre. Qul Sf Helth Cre. 2007;16: Kriplni S, LeFevre F, Philips CO, et l. Deficits in communiction nd informtion trnsfers between hospitl-bsed nd primry cre physicins: implictions for ptient sfety nd continuity of cre. JAMA. 2007;297(8): vn der Linden CMJ, Kerskes MCH, Bijl AMH, et l. Represcription fter dverse drug rection in the elderly: descriptive study. Arch Intern Med. 2006;166: Keywords: prescription dmission dischrge discontinuity psychotropic drugs represcription Frequency of lbortory mesurement nd hyperklemi in hospitlised ptients using serum potssium concentrtion incresing drugs Esther V. Uijtendl *, Jennette E.F. Zwrt-vn Rijkom b, Wouter W. vn Solinge bc nd Toine C.G. Egberts b Deprtment of Clinicl Phrmcy, University Medicl Centre Utrecht, Utrecht. b Deprtment of Phrmcoepidemiology nd Clinicl Phrmcology, Utrecht Institute for Phrmceuticl Sciences, Fculty of Science, Utrecht University, Utrecht. c Deprtment of Clinicl Chemistry nd Hemtology, University Medicl Centre Utrecht, Utrecht. * Correspondence: e.v.uijtendl@umcutrecht.nl. Objective Although drug drug interctions (DDIs) between potssiumincresing drugs (PIDs) re known risk fctors for developing hyperklemi, not much is known bout their risk nd mngement strtegies during hospitlistion. This study describes the frequency of serum potssium mesurement nd of hyperklemi for hospitlised ptients using one or more PIDs, nd determinnts thereof. Adult ptients hospitlised in the University Medicl Centre Utrecht in were included in this cross-sectionl study. Frequency of serum potssium mesurement nd hyperklemi were compred between ptients using only one PID t time (monotherpy group) nd ptients using two or more PIDs concomitntly (interction group). Determinnts studied were renl filure, dibetes mellitus, use of diuretics, type of DDI, strt of the PIDs within the hospitl versus continued home mediction, nd medicl specility.