Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Clinical value of an arterial pressure-based cardiac output measurement device. | Available online http content 12 1 403 Letter Clinical value of an arterial pressure-based cardiac output measurement device Joris Lemson and Johannes G van der Hoeven Department of Intensive Care Medicine Radboud University Nijmegen Medical Centre 6500 HB Nijmegen The Netherlands Corresponding author Joris Lemson Published 25 January 2008 This article is online at http content 12 1 403 2008 BioMed Central Ltd Critical Care 2008 12 403 doi cc6219 See related research by McGee et al. http content 11 6 R105 With interest we read the recent publication by William McGee and colleagues in which they conclude that arterial pressurebased cardiac output APCO measurement is comparable to intermittent thermodilution cardiac output ICO 1 . However the Bland Altman plot of APCO versus ICO shows a wide spread of data points with a percentage error of 42 . These large variations could lead to a completely different clinical management. Also we disagree that a percentage error less than 28 is a conservative requirement. By using an error-gram limits of precision of 20 for both test and reference method give predicted limits of agreement of 2 . These limits should be respected when an alternative cardiac output measurement technique is evaluated because limits of precision in excess of 20 for a single technique are not clinically acceptable. Furthermore the authors state that they only consider a change in cardiac output of 30 or more clinically relevant. This is in contrast to daily clinical practice in which cardiac output changes of 10 to 15 are frequently used for making decisions regarding therapy. Also they have calculated the change in cardiac output by dividing the delta cardiac output by the mean value before and after the change. In this way they have artificially decreased the relative change in cardiac output. Subsequently in the plot showing the change in ICO versus the change in APCO it can be .
