When performing umbilical cord Doppler, should you sample at the fetal insertion, placental insertion, or a free floating portion of the cord? I have heard different things and would like some clarification. The most recent article I have been able to find that states one or the other was published in 1999 by the Journal of Diagnostic Medical Sonography. It states that you should sample a free floating portion of the cord. Does anyone have any updated or more recent information on this topic?
Also, the same article speaks mostly about using S/D ratios to determine fetal outcome, however, Callen says that S/D ratios are being used less and less because if there is no end-diastolic flow the S/D ratio is no longer valid and that RI and PI are used more...mainly RI. Any information regarding this would also be appreciated!
If you read my first discussion, you will understand that my co-sonographer and I are just beginning to learn umbilical cord Doppler. Thanks for any help you can give us!
This is the link to the article that I referenced in this discussion: http://jdm.sagepub.com/cgi/content/abstract/15/2/59