A plea for balanced reporting

Abstract

I read with interest the study by Mayer and colleagues on intraoperative hemodynamic optimization using Flotrac/Vigileo [1]; however, the imbalance in their discussion needs redressing. Citing a meta-analysis of esophageal Doppler cardiac output (CO) validation studies that I co-authored [2], they claimed this showed 'limited accuracy' and that 'absolute CO measurements were found to be imprecise'. Surprisingly, they made no mention of a similar meta-analysis they published last year on the FloTrac/Vigileo system [3] where the precision and bias of the second generation device were no better! Clearly, they wish to promote the device they use and believe in, but it does no service to the medical and scientific community to misrepresent one technology over another. For example, they make no mention of the limitations of the 12% pulse pressure variation value used to predict fluid responsiveness; with tidal volumes <8 ml/kg, accuracy is only 51% [4] yet they did not report tidal volumes delivered. Nor do they mention the inferior results reported last year in an independent comparison of the two devices undertaken for the French Agence d'Evaluation des Produits de Sante [5]. They did acknowledge an overall reduction of hospital stay and complication rates in five Doppler-directed perioperative optimization studies (actually, nine such studies are published to date). Is this not at odds with the claimed 'imprecision'? They may be interested to learn of a recent UK National Health Service Technology Adoption Centre implementation project involving 1,247 surgical patients in 3 hospitals where these research findings could be reproduced in routine clinical practice, with a 3-day reduction in hospital stay and fewer postoperative complications [6]. I openly declare my affection for the Doppler technology. It too has its imperfections but the onus is on other monitoring devices to achieve consistently similar - if not better - outcomes in prospective randomized controlled trials. I conclude with a general plea to advocates of any device or management strategy to present a balanced view of advantages and limitations, and to move away from partisan reporting. The general knowledge base on CO monitoring devices is woefully inadequate so it is incumbent upon the aficionado to educate properly.