Abstract
In the Netherlands in 2010, 11% of patients with ischemic stroke received intravenous thrombolysis (IVT), varying from 4 to 26% between hospitals. The aim of this study was to investigate variation in clinical practice and organization of IVT in relationship to performance and outcome. In all 84 Dutch hospitals performing IVT, a stroke neurologist was approached using a web-based survey. The response rate was 82%. The study showed considerable variation. For example, door-to-needle time ranged from 25 to 80 min. High blood pressure was actively lowered before performing IVT by 57% of neurologists, while 35% chose to wait. 28% started IVT without knowledge of laboratory results. Better follow-up data are needed to see whether this variation results in differences in outcome.
Introduction
In the Netherlands in 2010, 11% of the patients with ischemic stroke received intravenous thrombolysis (IVT), varying from 4 to 26% between individual hospitals [1]. This variation is not explained by late arrival due to distance [2]. The present Dutch stroke guidelines [3] allow for variation in the indication of thrombolysis, such as management of high blood pressure. The aim of this study was to investigate variation in clinical practice and organization of IVT in relationship to performance and outcome.
Methods
In all 84 Dutch hospitals which performed IVT in 2010, a stroke neurologist was asked to participate in a web-based survey (http://www.enqueteviainternet.nl). The topics addressed were average door-to-needle time (DTNT), yearly number of IVT and intra-arterial thrombolyses, and outcome (Modified Rankin Scale after 3 months). Using the clinical directives from the present Dutch stroke guidelines [3], we identified situations where variation could be expected.
We studied associations between variation in treatment and effect on DTNT, percentage of thrombolysis within the hour, percentage of patients receiving IVT treatment (linear regression analysis, SPSS), and the effect of patient volume.
Results
69 stroke neurologists responded (82%). The yearly number of ischemic strokes treated in their hospitals ranged from 80 to 800 and the proportion receiving thrombolysis ranged from 5 to 36%. The average DTNT was 25-80 min (median 25-61).
High blood pressure was actively lowered by 57% of neurologists, whereas 35% waited for the blood pressure to drop spontaneously (fig. 1). 28% of neurologists started IVT without knowledge of the laboratory results, while 58% awaited at least the glucose results. Thrombocyte count was awaited by 23% of neurologists, before performing IVT, and international normalized ratio was awaited by 33% of neurologists.
Treatment strategies of the neurologists in the following situation: you consider treating a patient with thrombolysis; however, the blood pressure is too high (SBP >185 mm Hg or DBP >110 mm Hg).
Treatment strategies of the neurologists in the following situation: you consider treating a patient with thrombolysis; however, the blood pressure is too high (SBP >185 mm Hg or DBP >110 mm Hg).
In case of rapid but not complete recovery, 83% of neurologists did not refrain from using IVT. 36% of neurologists treated patients, who after complete recovery experienced a relapse, within 4.5 h after the first symptoms. 48% of neurologists considered the new symptoms as a new episode and treated them irrespective of the time which had elapsed since the first symptoms. 10% of neurologists did not withhold IVT in case of depressed consciousness. High age was a contraindication for 8% of neurologists. Use of oral anticoagulants with a normal international normalized ratio meant a contraindication for only 5% of neurologists.
No relationship between the number of IVT patients and DTNT (p > 0.05) was shown. In 31 centers (45%) information on the 3-month patient status was available, while in 35% of them this was assessed by means of the Modified Rankin Scale.
Discussion
We found considerable variation in clinical practice of IVT in the Netherlands, appearing from differences in the proportion of IVT treatment and in the management of clinical situations. This variation is likely to affect the number of patients eligible for IVT and may have an effect on clinical outcome. The influence and presence of this variation have been noted in other studies [4,5,6]. IST-3 shows that aged patients (>80) benefit from thrombolysis compared to placebo [7].
In our study a lack of follow-up data precluded analysis of the effect on performance and outcome. Self-reporting may have introduced bias. Participating stroke neurologists were not necessarily representative for the local policy. A systematic collection of follow-up data is needed to increase the knowledge on the effectiveness of IVT in diverse clinical situations [8].
Acknowledgements
We would like to thank the following neurologists for their participation in the study: L.A.M. Aerden, Reinier de Graaf Gasthuis, V.I.H. Kwa, Onze Lieve Vrouwe Gasthuis, F.B.J. Scholtens, Gemini Ziekenhuis, M. Hoebert, Gelre Ziekenhuizen, J.C.B. Verheij, Vlietland Ziekenhuis, M.F. Roesdi, Kennemer Gasthuis, P.G. Oomes, Ziekenhuis Bethesda Hoogeveen, H.W. ter Spill, Ruwaard van Putten Ziekenhuis, G.A. Sulter, Ziekenhuis De Sionsberg, S.F.T.M. de Bruijn, HagaZiekenhuis, E.J. van Dijk, UMC St. Radboud, R.M.J.A. Roebroek, Maasziekenhuis Pantein, J. Boiten, Medisch Centrum Haaglanden, E. Geiger, Beatrixziekenhuis, I.S. Beijer, Maxima Medisch Centrum, N.D. Kruyt, Slotervaartziekenhuis, A.L. Strikwerda, Het LangeLand Ziekenhuis, R.L.C. Vogels, Medisch Centrum Alkmaar, T.W.M. Raaijmakers, Meander Medisch Centrum, M.J.H. Wermer, Leids Universitair Medisch Centrum, M.P.J. van Goor, Laurentius Ziekenhuis, Y.B.W.E.M. Roos, Academisch Medisch Centrum, G.J. Biessels, Universitair Medisch Centrum Utrecht, A.M.H.G. van der Heijden-Montfroy, VieCuri Medisch Centrum, J.C. den Heijer, MC Leeuwarden, J.R. de Kruijk, Tergooiziekenhuizen, R.M. van den Berg-Vos, St. Lucas Andreas Ziekenhuis, A.H.C.M.L. Schreuder, Atrium Medisch Centrum, C.P. Zwetsloot, Waterlandziekenhuis, R.A. van der Kruijk, Slingeland Ziekenhuis, J.S.P. van den Berg, Isala klinieken, K. Keizer, Catharina Ziekenhuis, P.L.M. de Kort, St. Elizabeth Ziekenhuis, R.A.J.A.M. Bernsen, Jeroen Bosch Ziekenhuis, I.S.J. Merkies, Spaarne Ziekenhuis, E.W. Peters, Admiraal de Ruyter Ziekenhuis, G.J. Luijckx, Universitair Medisch Centrum Groningen, E.V. van Zuilen, Scheper Ziekenhuis, J.S. Straver, Zuwe Hofpoort Ziekenhuis, S.M. Manschot, Bronovo Ziekenhuis, H.L. van de Wiel, Ziekenhuis Nij Smellinghe, H.P. Bienfait, Gelre Ziekenhuizen, R.J. van Oostenbrugge, Academisch Ziekenhuis Maastricht, S.L.M. Bakker, St. Franciscus Ziekenhuis, R.C.F. Smits, Streekziekenhuis Koningin Beatrix, H. Kerkhoff, Albert Schweitzer Ziekenhuis, C.T.J.M. Leijzer, Röpcke-Zweers Ziekenhuis, W.A.J. Hoefnagels, ZorgSaam Zeeuws-Vlaanderen, P.J.A.M. Brouwers, Medisch Spectrum Twente, K. de Gans, Groene Hart Ziekenhuis, M. Liedorp, Havenziekenhuis Rotterdam, L. Zegerius, Rode Kruis Ziekenhuis, R.F. Duyff, Ziekenhuis De Tjongerschans, J. Hofmeijer, Rijnstate, H.C. Tjeerdsma, Lievensberg Ziekenhuis, R.J.J. Tans, MC Zuiderzee, D.W.J. Dippel, Erasmus MC, R. Saxena, Maasstad Ziekenhuis, H. Lövenich, St. Jans Gasthuis, E. Maasland, Het Van Weel-Bethesda Ziekenhuis, T.C. van der Ree, Westfriesgasthuis, G.W. van Dijk, Canisius-Wilhelmina Ziekenhuis, B.J.M. van Moll, IJsselland Ziekenhuis, R. van Dijl, Amphia Ziekenhuis, J. Trip, Diaconessenhuis Meppel, A.E. Boon, St. Annaziekenhuis, and E.L.L.M. de Schryver, Rijnland Ziekenhuis.
